EP2613884B1 - Comminution device - Google Patents

Description

The invention relates to a crushing device comprising a first cutting element, comprising at least a first cutting edge, a second, movable on a first movement path relative to the first cutting element cutting element comprising at least a second cutting edge, wherein the second cutting element abuts the first cutting element in such a way the relative movement of the second cutting element along the first trajectory causes a shearing action between the at least one first cutting edge and the at least one second cutting edge, an adjuster mechanism which adjusts the second cutting element relative to the first cutting element in a second trajectory such that upon wear of the first traction element and / or second cutting element as a result of the relative movement along the first movement path, the first cutting element is tracked for permanent contact with the first cutting element.

Cutting devices of this design are used to comminute solids, solid masses or solids-containing liquids and are used in particular as so-called. Wet crusher, for example in the food industry, the treatment of organic suspensions for further energy use or other agricultural uses mixed with solids mixed, flowable mixtures and in this case to crush the solids contained therein.

A cutting device of the type mentioned is out PCT / EP2010 / 053800 , also published as DE 20 2009 003 995 U , known. In this prior art comminution device, the first and second cutting element are formed by a fixed, circular perforated disc on the one hand and a rotating around the central axis of the perforated disc blade, which rests with a cutting edge on the surface of the perforated disc. The mass to be crushed is pressed through the holes in the perforated disc and thereby crushed by passing through the holes solids by a shearing action between the knife edge and an edge bounding the respective hole by shearing.

A fundamental problem that occurs in shredders of this type, is causally due to the wear of the two cutting elements, ie in the exemplary case on the one hand the perforated disc and in particular the other hand, the knife conditionally. In order to ensure a consistently consistent or at least only slightly deteriorated cutting performance despite this wear, it is generally known to provide an adjusting mechanism, which is designed to keep the two cutting elements always in contact with each other and if possible with a defined contact force to each other. From the above-mentioned prior art, for example, an adjusting mechanism in the manner of a ball freewheel with bias is known for this purpose. In addition to this technical solution but other functioning Nachstellmechanismen are known, for example Nachstellmechanismen which press and track a cutting blade on a perforated disc by a hydraulically transmitted clamping force and Nachstellmechanismen which cause by means of a preloaded worm gear such a tracking clamping force between two cutting elements.

The relevant requirement of such Nachstellmechanismen is on the one hand a reliable Nachstellbewegung, on the other hand, equally reliable preventing the lifting of the two cutting elements from each other when a harder solid is cut and thereby causes a partially significant, the two cutting elements apart urging force. For this purpose, in the prior art corresponding locking mechanisms are integrated into such Nachstellmechanismen that prevent the two cutting elements are brought from a once tracked position in a spaced-apart position short-term or permanent. This is achieved for example by the blocking effect of a ball-type freewheel in the aforementioned prior art, but can also be achieved in other embodiments by check valves in hydraulic lines or the like.

However, there is a drawback in the prior art and also the refinement of this utility model application in that a user is not easily able to determine the state of wear of at least one or both cutting elements. For this purpose, it would be necessary on a regular basis to disassemble the shredding device and to free it from residues of the solid-substance-containing liquid contained therein, so that the cutting elements can be subjected to an optical and, if necessary, metrological test so as to possibly become one to detect oncoming too high state of wear and a resulting failure of the crushing device before its entry.

The invention is therefore based on a first aspect of the object to provide a crushing device, which opens up a simple way to determine the state of wear.

This object is achieved in that the adjusting mechanism comprises a leak-free hydraulic cylinder which is mechanically operatively coupled between the first and the second cutting element to effect an adjustment movement between the first and second cutting element by an actuation of the hydraulic cylinder and by a pressurization of the hydraulic cylinder Concurrently effected concerns of the first and second cutting element, and that the hydraulic cylinder is in hydraulic communication with a hydraulic pneumatic closed volume comprising a pressure vessel whose volume is filled to a first part with a hydraulic fluid and to a second part with air and the wall thereof is formed at least partially transparent for reading the hydraulic fluid level along a scale, which occurs in the operating boundary area between an air volume fraction and a hydraulic volume fraction in defines the hydraulic-pneumatic closed volume and reflects a state of wear of the first and second cutting element.

According to the invention, a specific type of adjusting mechanism is provided according to the first aspect, which is designed such that there is a comfortable Ablesemöglichkeit for the state of wear of the two cutting elements. In this case, the invention makes use in a special way that a hydraulic adjustment on the one hand, if it experiences an air cushion in the hydraulic system pressurization, at a sufficiently large ratio between the volume of the air cushion and the hydraulic volume moved by the Nachstellbewegung a nearly achieved constant biasing force over the entire Nachstellweg, but at the same time opened by the water level readability of the trailing path. This reading option is formed by a leak-free hydraulic cylinder, in particular by a total leakage-free hydraulic system of such a type that thereby a readout of the wear state on the basis of the hydraulic fluid level is made possible over the entire service life of the cutting elements.

According to the invention, a leak-free hydraulic cylinder or a leakage-free hydraulic system is to be understood as meaning a hydraulic cylinder or hydraulic system which exclusively uses hydraulic components which completely prevent the escape of hydraulic fluid from the pressure side. In this understanding and in the context of the invention, such hydraulic systems are considered to be non-leakage designed such that hydraulic fluid exiting the pressure system, for example, due to a partially desired leakage in a hydraulic actuator, this hydraulic fluid is then collected in a collecting memory and is returned to the hydraulic pressure system by means of a hydraulic pump. Decisive for the function according to the invention is that the volume of the total hydraulic fluid moved in the hydraulic system on the pressurized side does not change over the entire period of use of the comminuting device.

Basically, a pressurization or under the term pressure in the sense of this description and the appended claims to understand that this is an overpressure or a negative pressure relative to the ambient pressure is called. In this sense, the adjustment mechanism can thus be done by an overpressure or vacuum loading of the hydraulic cylinder.

For the purposes of this description and the claims, a hydraulic cylinder is to be understood as a hydraulic actuator of any design that converts a hydraulic pressure into a mechanical force and movement. This can be done for example by a linear cylinder or a rotary cylinder. According to the invention, the hydraulic cylinder is mechanically functionally coupled between the first and second cutting elements. Under this functional coupling of the hydraulic cylinder between the first and second cutting element is in this case no real spatial arrangement of the hydraulic cylinder between the first and second cutting element to understand. Instead, this is to be understood by the fact that the hydraulic cylinder is mechanically coupled either directly or via force-transmitting elements, such as levers, pressure or tie rods or the like of such kind with the two cutting elements, that the movement or force generated in the hydraulic cylinder relative movement and relative application of force causes a cutting element with respect to the other cutting element. In this way, a defined contact force of the two cutting elements is achieved and at the same time causes an adjustment when the two cutting elements wear. Basically, this functional coupling of the hydraulic cylinder, for example take place by the one cutting element is fixedly mounted in a housing to which the cylinder part of the hydraulic cylinder is fixedly coupled and the other cutting element is arranged relatively movable to this first cutting element within the housing and the piston of the hydraulic cylinder via a push rod or the like with this second cutting element is coupled. In other embodiments, a hydraulic rotary cylinder with its cylinder housing fixedly coupled to a housing and a first cutting element mounted thereon and the rotational movement of the hydraulic cylinder are transmitted via a worm gear on a push rod which acts on a second cutting element and this relative to the housing with respect to moves the first cutting element.

A hydraulic-pneumatic closed volume is to be understood as meaning a system constructed from one or more pressure vessels and the hydraulic cylinder and these components, compressed air lines, valves and the like, which is closed to the environment. According to the invention, such a hydraulic-pneumatic closed volume is provided with a pressure vessel which at least partially comprises a transparent wall. In an exemplary embodiment, this may be a glass cylinder or glass beaker, in which, when correctly installed, the boundary between hydraulic fluid and air in the hydraulically-pneumatically closed volume, namely at each position of the two cutting elements moving due to wear. In other embodiments, this level reading can be done by a transparent strip that extends across the level in the wall as a wall part. In the area of this hydraulic fluid level, a scale is provided which assigns the hydraulic fluid directly to a state of wear, for example by a scale of 100% to 0% drawn there as a scale or by the adjustment in a unit length, for example in mm, is entered as a scale.

With the solution according to the invention, a simple and at the same time reliable readjusting movement and contact pressure between two wearing cutting elements is provided, which in itself makes possible a simple reading of the state of wear. In this case, it is avoided according to the invention that a disassembly or partial disassembly of the comminution device must take place in order to detect the state of wear. It is also avoided that, for the purpose of indicating the state of wear, additional components, such as the sensors which detect the wear due to displacement sensing, are avoided. the wear by a weight measurement on one or both cutting elements detecting sensors or the like, with appropriate signal processing and signal display, must be provided.

According to a first preferred embodiment, it is provided that the hydraulic-pneumatic closed volume via a compressed air line with a check valve with an air pump or a compressed air port for pressurizing the pressure vessel is in communication and the check valve acts so that there is a flow from the pressure vessel into the air pump or prevents the compressed air connection.

With this training, a filling of the closed volume is made possible with a pressurized air and this prevents unwanted discharge or inflow of air from the volume out. Preferably, the compressed air line is connected to a volume portion of the closed volume in which there is no hydraulic fluid.

According to a further preferred embodiment, it is provided that the hydraulic cylinder is adjustable between a first position, in which the two cutting elements abut each other in an unworn new state, and a second position, in which the two cutting elements abut each other in a worn and an exchange-requiring consumption state is and between these two positions has a hydraulic volume change, and that this volume change corresponds to a maximum of twenty percent, preferably at most ten percent of the air volume fraction in the hydraulic-pneumatic closed volume.

With this configuration, the volume expansion, which takes place by an adjusting movement of the completely unworn to the fully worn state of the cutting elements, set in such a ratio to the air volume fraction in the hydraulic-pneumatic closed volume, that by the expansion of this air volume fraction no significant reduction in the biasing force takes place, with which the two cutting elements are pressed together. It should be understood that the air volume fraction is calculated as the total volume of air in the closed volume and the hydraulic volume change can usually be calculated by the hydraulically effective cross-sectional area of the hydraulic cylinder can be calculated with the travel of the hydraulic cylinder between the first, unworn and the second, worn position.

Alternatively to this solution can also be provided to divide the hydraulic-pneumatic closed volume into a volume filled with air and filled with air and hydraulic fluid volume and to connect these two volumes via an adjustable pressure reducing valve with each other. In this way, in the hydraulic fluid, a constant pressure over the entire Nachstellweg be maintained as long as the pressure in the air-filled volume above the pressure in the filled with air and hydraulic fluid volume and can be correspondingly reduced to a constant level.

Still further, it is preferable that the hydraulic cylinder is adjustable between a first position, in which the two cutting elements abut each other in an unworn new state, and a second position, in which the two cutting elements abut each other in a worn and an exchange-requiring consumption state, and between these two positions has a hydraulic volume change, and that the pressure vessel in the region of the scale has a cross-sectional area along the level which is at most so large that the ratio between the hydraulic volume change of the hydraulic cylinder and the cross-sectional area greater than 1cm, preferably greater than 2cm is. With this preferred embodiment, the level change that results in the course of an adjustment movement, is designed to such a size that a sufficient resolution when reading the state of wear is achieved. It should be understood that in the relevant interpretation on the one hand, the hydraulically effective cross-sectional area of the hydraulic cylinder as an influencing variable and in particular their relationship to the cross-sectional area of the level, ie the surface of the hydraulic fluid in the interface to the air volume. On the other hand, a possibly provided leverage of the movement of the hydraulic cylinder with respect to the Nachstellbewegung the two cutting elements influence each other, for example, when the cylinder movement is reduced, so that a travel of the cylinder causes a Nachstellweg the two cutting elements, which is smaller than the travel , or that the cylinder is translated, that is achieved by a small travel a larger Nachstellweg. In the sense of a sufficient reading accuracy, the smallest possible cross-sectional area is to be provided, in which case it should be understood as limiting that, for the purpose of sufficient compactness of the entire structure of the invention This optimization approach finds its limit among other things in the overall dimensions.

Still further, it is preferred that the hydraulic cylinder act on a transmission rod which transmits an adjusting force to a second rotating cutting element and which is guided within a hollow shaft which transmits a rotational movement from a drive motor to the second cutting element and a first cutting element through a cutting screen is formed, which has a plurality of openings whose boundary edges forming cutting edges along which the second cutting element is rotatably moved, thereby causing a shearing action between the first cutting element and the cutting edges of the second cutting element. With this embodiment, a particularly efficient comminuting action is achieved and at the same time a mutually favorable for this type of movement of the two cutting elements, in particular robust and manufacturing technology advantageous transfer of the cutting forces and the Nachstellkräfte achieved.

Still further, it is preferable that the pressure vessel and the air pump are integrally formed on a pressure unit and the air pump includes a piston connected to a manual operation handle via a piston rod, and further comprising a cylinder sealingly receiving the piston, preferably pivotally mounted on the printing unit. With this training, a compact and integral structure of the entire Nachstellmechanismus is achieved, which makes in particular a leak-free execution particularly reliable executable. Due to the integral design of an air pump to the printing unit a substantial independence of the crushing device is achieved, which is made possible in particular by the fact that after a single pressurization, the operation of the crushing device both in terms of the required biasing force of the two cutting elements as well as their adjustment to each other without further compressed air supply from the outside is ensured.

Still further, it is preferable that the pressure vessel comprises a first pressure vessel having a first portion for hydraulic fluid and a second portion for air, the wall of which is formed at least partially transparent for detecting the level of the hydraulic fluid and having a scale for reading the state of wear , and a compressed air tank, which is connected to the section for air of the first container via a compressed air line, and that the compressed air tank is in communication with the air pump or compressed air connection.

This embodiment divides the closed volume into two containers, wherein in a first container both hydraulic fluid and air volume is located and thus this container comprises the level required for reading and has a corresponding scale. Preferably, this first container may be bounded by a glass tube or a glass cup to thereby facilitate the readability in a simple manner. Furthermore, according to this embodiment, a second compressed air tank is provided which contains only compressed air. With this configuration, the provision of a large volume of air from the tank having the level to a constant biasing force is displaced into a compressed air tank and thereby in particular allows the tank comprising the level to have a level cross sectional area optimized for high resolution readability, i. a small cross-sectional area, which allows a comparatively large level change over the entire adjustment path of the two cutting elements. The preferably large volume of air is then provided via a second container, the compressed air tank, which may have a correspondingly large cross-section, thereby providing the above-described preferably large ratios between the air volume and the volume changed by the Nachstellbewegung volume throughout the closed system. In particular, this embodiment is preferred when the first pressure vessel and the compressed air tank are connected to each other via an adjustable pressure reducing valve, in this case, the compressed air tank acts as a pressure reservoir for this pressure reducing valve.

According to a further preferred embodiment, it is provided that the compressed air tank is connected to a first pressure vessel containing hydraulic fluid and an air volume via an adjustable pressure reducing valve, which can be adjusted between at least one, preferably at least two of the following valve positions: in which the compressed air tank and the first pressure vessel connected to each other and shut off from the ambient pressure, a second position in which the compressed air tank is connected to the ambient pressure and the first pressure vessel is shut off from the ambient pressure and the compressed air tank, a third position in which the first pressure vessel connected to the ambient pressure and the compressed air tank is shut off from the ambient pressure and the compressed air tank, a fourth position in which the first pressure vessel and the compressed air tank are connected to the ambient pressure, and / or a fifth position in which the first pressure vessel is shut off from the compressed air tank and the first pressure vessel and the compressed air tank are shut off from the ambient pressure, wherein the multi-way valve in the first, second, third and / or fourth position preferably acts as an adjustable pressure reducing valve. This adjustable pressure reducing valve thus makes it possible, on the one hand, to connect the first pressure vessel to the ambient pressure while maintaining the pressure in the compressed air tank, and thus to allow the cutting elements to be moved relative to one another, without the hydraulic cylinder being disengaged from its coupling with this two cutting elements would have to be removed mechanically and thus comfortably perform a change of one or both cutting elements. After the change can take place by appropriate transverse position of the pressure reducing valve, the pressurization of the first pressure vessel from the compressed air tank. Furthermore, with the pressure reducer valve, the pressure in the entire system can be lowered by connection to the ambient pressure and, as a result, an adjustment of the contact force between the two cutting elements can be achieved. By the Druckminderungswwirkung of the pressure reducing valve, a constant pressure in the first pressure vessel is maintained when the volume expands, as long as the pressure in the compressed air tank is above the pressure in the first pressure vessel. In addition, vibrations that build up in the hydraulic-pneumatic volume can be prevented or at least reduced.

Still further, it is preferable if between the second cutting element and a hollow shaft for transmitting the cutting force along the first movement path, a positive connection is formed, which is positively formed in a circumferential direction for transmitting the required driving force for the first movement path and in an axial direction is movable for performing an adjustment movement along the second movement path. With this embodiment, a constructive and manufacturing technology particularly advantageous form for the hydraulic transmission of an adjusting force is realized, which can achieve a continuous and reliable adjusting movement of a rotating blade.

It is even further preferred that a lubricant-filled cavity is formed between a first surface formed on the first cutting element or a component coupled to the first cutting element and a second surface formed on the second cutting element or a component coupled to the second cutting element is formed, whose volume is reduced by an adjusting movement of the second cutting element along the second movement path and which is in fluid communication with the positive connection in the supply of lubricant to the positive connection (see also the comments on the second aspect of the invention). This training is initially based on the finding that the decreasing over a longer period of operation with demanding crushing cutting effect is due to the fact that the positive connection for transmitting the cutting movement between the first and second cutting element, so the relative movement along the first trajectory due to such stress no longer reliably allows the adjustment movement along the second path of movement. This is due to the fact that subsidence phenomena occur in this positive connection on the one hand by cyclic stress, on the other hand, but also by this type of stress in conjunction with the often aggressive media whose access to the positive connection can not always be reliably prevented, an adhesive effect associated with by corrosion or pollution-related adhesive forces, whereby a movement along the second movement path counteracting clamping can occur. This has the effect that the desired readjusting movement of the two cutting elements for wear compensation is not achieved uniformly, but does not take place irregularly or in part, as a result of which at least temporarily, in part permanently, a gap between the first and second cutting element which reduces the quality and performance of cutting, ie first cutting element no longer or no longer completely rests on the first cutting element.

This problem is solved by training by a lubrication of the positive connection. In this case, the invention provides that this lubrication is achieved in a simple yet reliable manner by providing a cavity in the region of the adjusting mechanism, from which a lubricant in the region of the surfaces moving relative to one another for movement along the second movement path is lubricated can promote. The promotion of this cavity is achieved according to the invention by the cavity of such kind is limited by walls, which are in communication with each other by the Nachstellbewegung moving components and thereby reduce the volume of the cavity during an adjusting movement. A lubricant in the cavity is in this configuration at each readjustment movement with the resulting reduction in volume of the cavity in small portions between the relatively moving parts of the positive connection promoted and thereby causes a running and low-dose lubrication of the positive connection. This lubrication is achieved without an additional lubricant pump or the like and without their own drive and takes place in a metered manner by the self-lubricating readjustment itself. The cavity can be sized such that over a long period of time a supply of lubricant is ensured in the positive connection, In particular, it can be provided that the cavity can be refilled with lubricant from the outside. For example, this may be necessary if one of the two cutting elements or both must be replaced due to serious wear and the Nachstellmechanismus is thereby reset to an initial position, whereby the cavity is expanded to its initial size and then filled with lubricant.

It is particularly preferred if the lubricant-filled cavity is connected to a lubricant nipple for supplying lubricant into the cavity. This configuration makes it possible to fill the cavity with new lubricant at regular maintenance intervals, it being understood in principle that the cavity can always be filled with such an amount of lubricant that it lubricates the positive connection over the entire adjusting period of the operation of a cutting element pairing ensures, ie from the installation of new cutting elements to the wear-related change of these cutting elements, and then to fill the cavity with new lubricant after returning the Nachstellmechanismus to an initial position and replacement of one or both cutting elements. In principle, the lubricant according to the invention is in particular a hydrocarbon-based grease, in particular mineral oil-based, although other lubricants such as silicone-containing lubricants, graphite-containing lubricants, soap-based lubricants or liquid lubricants such as mineral oils or synthetic oils can be used.

Still further, it is preferable that the second trajectory is perpendicular to the first trajectory. With this embodiment of the two trajectories, an efficient readjusting movement to compensate for the wear caused by the movement along the first trajectory is achieved.

According to a further preferred embodiment it is provided that the first cutting element is a perforated disc and a plurality of first cutting edges are formed by openings in the perforated disc bounding walls, and the second Cutting element comprises a rotating on the surface of the perforated disc along the first path of movement of the knife. The perforated disc may in this case be in particular circular and have a multiplicity of openings, such as bores, triangular or trapezoidal recesses or passage openings of other cross section. On the one hand, this design enables an efficient media guidance, in that the openings of the first cutting element are flowed through by the solids to be cut. On the other hand, an effective cutting action distributed over many cutting edges on the first cutting element is achieved by forming a plurality of first cutting edges on the first cutting element through the boundary edges of the openings and having one or more cutting edges in the shape of those on the first cutting edge Cutting element rotating blades are formed.

Finally, according to a further preferred embodiment, it is provided that the second cutting element comprises a knife rotating on the surface of the first cutting element along the first movement path, and the form-locking connection is formed between a knife holder receiving the knife and a drive shaft driving the knife, in particular a form-fitting shaft Hub connection between a shaft driving the second cutting element and a hub body holding the second cutting element, in particular a splined connection or a feather key connection. In this embodiment, the drive element is formed by a drive shaft, which can be driven for example by an electric motor and causes a rotating movement of the blade on the first cutting element. It should be understood in principle that the second cutting element are also formed by a plurality, for example two, three or four knives, which are spaced apart from each other by a circumferential angle and are driven together. It can further be provided that the drive shaft is axially displaced even for an axial displacement movement of the second cutting element or that this another element, such as a pull or push rod, which is guided in a drive shaft designed as a hollow shaft, this axial movement for the readjustment causes.

Fig. 1

eine längsgeschnittene Seitenansicht einer erfindungsgemäßen Zerkleinerungsvorrichtung gemäß dem ersten Aspekt ohne hydraulisch betätigten Nachstellmechanismus,

Fig. 2

eine perspektivische Ansicht der Zerkleinerungsvorrichtung gemäß Fig. 1

Fig. 3

eine schematische Darstellung des hydraulischen Nachstellmechanismus der bevorzugten Ausführungsform gemäß den Figuern 1 und 2,

Fig. 4

eine Frontalansicht einer Hydraulikeinheit der erfindungsgemäß bevorzugten Ausführungsform gemäß dem ersten Aspekt in einer teilgeschnittenen Ansicht,

Fig. 5

eine Ansicht entlang des Schnittes B-B aus Fig. 7 der Ausführungsform gemäß Fig. 3 in einer vollständig längs geschnittenen Ansicht,

Fig. 6

eine entlang des Schnittes C-C in Fig. 7 längsgeschnittene Seitenansicht der Hydraulikeinheit gemäß Fig. 3,

Fig. 7

eine Detailansicht des oberen Anteils der Hydraulikeinheit gemäß Fig. 4,

Fig. 8

eine quer geschnittene Draufsicht gemäß des mit A-A bezeichneten Schnitts in Fig. 3,

Fig. 9

eine Detailansicht des mit Z bezeichneten Mittelbereichs in Fig. 5,

Preferred embodiments of the invention will be described in more detail with reference to preferred embodiments and with reference to the accompanying figures. Show it:

Fig. 1

1 is a longitudinal sectional side view of a crushing device according to the invention according to the first aspect without hydraulically actuated adjusting mechanism,

Fig. 2

a perspective view of the crushing device according to Fig. 1

Fig. 3

1 is a schematic representation of the hydraulic adjusting mechanism of the preferred embodiment according to FIGS. 1 and 2;

Fig. 4

a front view of a hydraulic unit of the present invention preferred embodiment according to the first aspect in a partially sectioned view,

Fig. 5

a view along the section BB Fig. 7 the embodiment according to Fig. 3 in a completely longitudinal view,

Fig. 6

one along the section CC in Fig. 7 longitudinal sectional side view of the hydraulic unit according to Fig. 3 .

Fig. 7

a detailed view of the upper portion of the hydraulic unit according to Fig. 4 .

Fig. 8

a cross-sectional plan view according to the designated AA in section in Fig. 3 .

Fig. 9

a detailed view of the center area designated Z in Fig. 5 .

Referring first to Fig. 1 and 2 The principle of the comminution function of a comminution device according to the invention according to the first aspect is explained below. The crushing device comprises an inlet opening 110, through which solids-laden liquids are supplied. The solids-laden liquid impinges on an annular orifice plate 120 which is provided with a plurality of openings through which the solids and liquid can pass. The perforated disc is fixedly mounted on an outlet housing 130 into which the solids-laden fluid enters after the comminution of the solids contained therein and can leave this outlet housing through an outlet opening in the radial direction.

On the side facing the inlet opening of the perforated disc 120, a knife holder 140 with a total of four blades 141 a - d disposed thereon is arranged. The blades 141a-d are located with their cutting edges on the surface 121 of the perforated disk 120 facing the inlet opening. Each blade 141 a - d extends in the radial direction, starting from a rotational axis 100 concentric with the central longitudinal axis of the perforated disc 120.

The knife holder 140 with the knives 141 ad attached thereto is set in rotary motion by means of a hollow drive shaft 150 about this axis of rotation 100, as a result of which the knives rotate in a circular path on the perforated disc 120. As a result, a shearing action is achieved between the knife edges and the boundary edges of the holes within the perforated disc, which results in the comminution of the solids entering the holes.

The rotational movement is transmitted from the hollow shaft 150 to the knife holder 140 via a shaft-hub connection 151. The shaft-hub connection allows axial mobility of the knife holder 140 to the hollow shaft 150th

The hollow shaft 150 is driven by a drive motor 190 and transmits the rotary motion to the blades 141 a - d.

The drive shaft 150 is designed as a hollow shaft and transmits the torque by means of a splined connection 154 on the blades 141 a - d. The blades 141 a - d are axially movable but guided torque-tight with respect to the hollow shaft 150 in the spline connection 154 and can thereby perform an adjustment movement of the cutting blades 141 a, b on the cutting screen 120.

In the hollow shaft 150, a pull rod 160 is guided. The pull rod 160 transmits the axial clamping and adjusting force of a thereto on the axial end 161 of the pull rod 160 Nachstellantriebsvorrichtung on the fair holder 140th

The adjuster drive device comprises a cylinder 165 which is fixedly connected to the hollow shaft and in which a piston 166 is mounted so as to be axially displaceable. The piston 166 is fixedly connected to the pull rod 160. On the piston 160, a hydraulic connection element 167 is attached, by means of which hydraulic fluid can be pressed under pressure into the intermediate space 168 between the piston 166 and the cylinder 165. Fig. 1 shows the crushing device according to the invention in a state in unworn, new cutting elements 141 a, b, 120. From the position shown, the piston 166 can lift up from the cylinder 165 and pulls the pull rod 160 in the direction of the arrow 102 out of the hollow shaft 150, whereby the cutting blades 141 a, b are moved in the direction of the cutting screen 120.

Between a front-side annular surface 153 at the end of the drive shaft 150 arranged in the region of the knives 141a-d and an annular bottom surface 163 in a blind bore receiving the drive shaft end in the knife holder 140, a cavity 180 is arranged, into which a lubrication nipple 182 and a lubrication bore 181 Lubricant can be filled from the outside. Due to the approach of the end faces 153, 163, this hollow space reduces its volume when a readjusting movement of the knife holder 140 takes place in the direction of the arrows 101. In this way, lubricant arranged in the cavity 180 is pressed into the lubricating gap 183 in the area of the splined connection and thereby reliably ensures mobility and reliable readjusting movement of the cutting blades 141a-d with respect to the cutting screen 120.

The pull rod 160 is acted upon by a unidirectional linear hydraulic cylinder 210. The hydraulic cylinder 210 is coupled to the pull rod 160 such that upon application of pressure to the hydraulic cylinder and consequent extension of the hydraulic cylinder onto the pull rod 160, a pulling force is transmitted to the cutters 141a - Press d on the cutting screen 120.

Fig. 3 shows schematically the structure of the hydraulic system. The hydraulic cylinder 210 is connected to a level pressure vessel 220 by means of a parallel check valve 211 and a throttle 212. In the level pressure vessel 220, hydraulic oil is disposed in a lower portion 220a, which also fills the communication line to the hydraulic cylinder 210 and its pressurized side.

The level pressure vessel 220 further has an air volume 220b in a volumetrically approximately equal ratio to the oil therein. Between the air volume 220 b and the hydraulic oil volume 220 a, an oil level 221 is formed.

The level pressure vessel 220 further includes a scale 222. The level pressure vessel 220 is made of a pressure-resistant glass cup with a metallic cap, so that the level between air and hydraulic oil can be read from the outside. On the glass cup, a scale 222 is arranged, which makes it possible to assign the level to an extension of the hydraulic cylinder 210. This extended state of the hydraulic cylinder 210 in turn corresponds to a Nachstellweg and consequently a state of wear of the cutting blades 141 a - d and the cutting screen 120. Here, the wear state of the cutting blade and the cutting screen as cumulative wear of both sides is visualized by the level on the scale.

The filled with air 220b portion of the level pressure vessel 220 is connected by means of an air pressure line 231 with a compressed air tank 230. In the compressed air line 231, an adjustable pressure reducing valve 232 is used. This pressure reducing valve 232 makes it possible to selectively connect the compressed air tank or the level pressure vessel 220 to the ambient pressure. Furthermore, the compressed air tank 230 and the level pressure vessel 220 can also be connected via the pressure reducer valve 232 to the ambient pressure. In a normal operating position, the pressure reducing valve 232 connects the compressed air reservoir with the level pressure vessel and blocks both containers from the environment. In this normal operating position, a constant pressure in the level pressure vessel is maintained even if due to an increase in volume by displacement of the piston in the hydraulic cylinder 210, the total air volume expands as long as the pressure in the compressed air tank 230 is higher than in the level pressure vessel 220th

At the compressed air tank 230, a manually operable air pump 240 is connected and fixed via a check valve 241. By means of the air pump 240, a desired internal pressure can be built up in the compressed air tank to thereby produce a contact pressure between the cutting blades 141 a - d and the perforated wire 120 by means of the hydraulic oil in the hydraulic-pneumatic closed system.

The FIGS. 4 to 9 show the hydraulic unit of the crushing device according to the invention in different views. As can be seen, this hydraulic unit comprises a glass cup 225, which has on the bottom side a connection 226 for connection to the hydraulic cylinder 210. On the glass wall of the glass cup 225, the scale 222 is printed.

The glass cup 225 is sealingly fixed by means of a screw 227 to a housing body 235. In the housing body 235 of the compressed air tank 230 is arranged as a cavity and sealed by an upper cover 236.

As in particular from the Figures 5 and 8th it can be seen, the compressed air tank 230 can be acted upon either by means of a manually operated air pump 240 with compressed air. Alternatively, the compressed air tank 230 can also be acted upon by compressed air via a compressed air connection 250.

The compressed air tank 230 is connected by means of a longitudinal bore 233, which opens into a transverse bore 234 and a diagonal bore 228 with the level pressure vessel. In the transverse bore 234, a valve insert is used, which can be actuated from the outside and allows either the compressed air tank or the level pressure vessel is connected to ambient pressure or the compressed air tank and the level pressure vessel connected to each other and are closed by the ambient pressure.

On the hydraulic unit further two pressure gauges 261, 262 are arranged. The upper pressure gauge 261 indicates the air pressure in the compressed air tank 230. The lower pressure gauge 262 shows the pressure in the level pressure vessel.

Claims (14)

1. Comminution device, comprising,

   - a first cutting element (120, 320; 420) comprising at least one first cutting edge,

   - a second cutting element (141 a-d, 340a, b; 440a-d) movable on a first movement path in relation to the first cutting element and comprising at least one second cutting edge,
   the second cutting element bearing against the first cutting element in such a way that the relative movement of the second cutting element along the first movement path brings about a shearing action between the at least one first cutting edge and the at least one second cutting edge,

   - an adjusting mechanism (160-166, 350, 360, 370; 460) which adjusts the second cutting element in relation to the first cutting element on a second movement path in such a way that, in the event of wear of the first and/or the second cutting element as a result of the relative movement along the first movement path, the first cutting element is guided so as to bear permanently against the first cutting element,
   characterized in that the adjusting mechanism comprises a leakage-free hydraulic cylinder (165, 167) which is mechanically coupled functionally between the first and the second cutting element, in order

   - to bring about an adjusting movement between the first and the second cutting element as a result of actuation of the hydraulic cylinder, and

   - to cause the first and the second cutting element to bear one against the other by the action of pressure on the hydraulic cylinder,

   - and in that the hydraulic cylinder is connected hydraulically to a hydraulically pneumatic closed volume (220, 230) which comprises a pressure vessel, the volume of which is filled with a hydraulic fluid in a first part (220a) and with air in a second part (220b) and the wall of which is designed to be at least partially transparent for the purpose of reading off the hydraulic fluid level along a scale (222) which

   - defines the limit range occurring during operation between an air volume fraction and a hydraulic volume fraction in the hydraulic-pneumatic closed volume, and

   - reproduces a state of wear of the first and of the second cutting element.
2. Comminution device according to Claim 1, characterized in that the hydraulic-pneumatic closed volume is connected via a compressed-air line having a non-return valve (241) to an air pump (240) or to a compressed-air connection (250) for acting with compressed air upon the pressure vessel, and the non-return valve acts such that it prevents a volume flow out of the pressure vessel into the air pump or the compressed-air connection.
3. Comminution device according to Claim 1 or 2, characterized in that the hydraulic cylinder can be adjusted between a first position, in which the two cutting elements bear one against the other in a non-worn new state, and a second position, in which the two cutting elements bear one against the other in a worn state of consumption requiring exchange, and has a hydraulic volume change between these two positions, and in that this volume change corresponds at most to twenty percent, preferably to at most ten percent, of the air volume fraction in the hydraulic-pneumatic closed volume.
4. Comminution device according to one of the preceding claims, characterized in that the hydraulic cylinder can be adjusted between a first position, in which the two cutting elements bear one against the other in a non-worn new state, and a second position, in which the two cutting elements bear one against the other in a worn state of consumption requiring exchange, and has a hydraulic volume change between these two positions, and in that the pressure vessel has in the region of the scale, along the level, a cross-sectional area which at most is such that the ratio between the hydraulic volume change of the hydraulic cylinder and the cross-sectional area is greater than 1cm, preferably greater than 2cm.
5. Comminution device according to one of the preceding claims, characterized in that the hydraulic cylinder acts upon a transmission rod (160) which transmits an adjusting force to a second rotating cutting element (141a-d) and which is guided inside a hollow shaft (150) which transmits a rotational movement from a drive motor (190) to the second cutting element, and in that a first cutting element is formed by a cutting screen (120) having a multiplicity of orifices, the boundary edges of which form cutting edges, along which the second cutting element is moved in rotation such that a shearing action between the first cutting element and the cutting edges of the second cutting element is thereby brought about.
6. Comminution device according to one of the preceding claims, characterized in that the pressure vessel and the air pump are formed integrally on a pressure unit, and the air pump comprises a piston which is connected via a piston rod to a handle for manual actuation, and, furthermore, comprising a cylinder which sealingly receives the piston and which is preferably fastened pivotably to the pressure unit.
7. Comminution device according to one of the preceding claims, characterized in that the pressure vessel

   - comprises a first pressure vessel (220),

   - which has a first portion (220a) for hydraulic fluid and a second portion (220b) for air,

   - the wall (225) of which is designed to be at least partially transparent for the purpose of detecting the level (221) of the hydraulic fluid and

   - which has a scale (222) for reading off the state of wear and

   - comprises a compressed-air vessel (230) which is connected to the portion for air of the first pressure vessel via a compressed-air line (231),

   and in that the compressed-air vessel is connected to the air pump (240) or to the compressed-air connection (250), preferably via an adjustable pressure-reducing valve.
8. Comminution device according to the preceding claim, characterized in that the compressed-air vessel is connected to the first pressure vessel via an adjustable pressure-reducing valve (232) which can be adjusted between at least one, preferably at least two, of the following valve positions:

   - a first position, in which the compressed-air vessel and the first pressure vessel are connected to one another and are shut off from the ambient pressure, and

   - a second position, in which the compressed-air vessel is connected to the ambient pressure and the first pressure vessel is shut off from the ambient pressure and from the compressed-air vessel,

   - a third position, in which the first pressure vessel is connected to the ambient pressure and the compressed-air vessel is shut off from the ambient pressure and from the compressed-air vessel,

   - a fourth position, in which the first pressure vessel and the compressed-air vessel are connected to the ambient pressure,

   - a fifth position, in which the first pressure vessel is shut off from the compressed-air vessel and the first pressure vessel and the compressed-air vessel are shut off from the ambient pressure,

   the pressure-reducing valve acting in the first, the second, the third and/or the fourth position preferably as an adjustable pressure-reducing valve for setting a lower pressure in the first pressure vessel compared to the compressed-air vessel.
9. Comminution device according to one of the preceding claims, characterized in that, between the second cutting element and a hollow shaft for transmitting the cutting force along the first movement path, a positive connection (354; 454) is formed, which

   - is designed to be positive in a circumferential direction for the purpose of transmitting the drive force required for the first movement path and

   - is movable in an axial direction (300) for the purpose of executing an adjusting movement along the second movement path.
10. Comminution device according to one of the preceding claims, characterized in that, between a first surface formed on the first cutting element or on a component coupled to the first cutting element and a second surface formed on the second cutting element or on a component coupled to the second cutting element, a lubricant-filled cavity is formed, the volume of which decreases as a result of an adjusting movement of the second cutting element along the second movement path and which is fluidically connected to the positive connection for the purpose of feeding lubricant to the positive connection.
11. Comminution device according to Claim 10, characterized in that the lubricant-filled cavity is connected to a lubricant nipple for the purpose of feeding lubricant into the cavity.
12. Comminution device according to one of the preceding claims, characterized in that the second movement path lies perpendicularly to the first movement path.
13. Comminution device according to one of the preceding claims, characterized in that

    - the first cutting element is a perforated disc and a plurality of first cutting edges are formed by orifices in the walls delimiting the perforated disc, and

    - the second cutting element comprises a knife rotating on the surface of the perforated disc along the first movement path.
14. Comminution device according to one of the preceding claims, characterized in that

    - the second cutting element comprises a knife rotating on the surface of the first cutting element along the first movement path, and

    - the positive connection is formed between a knife holder receiving the knife and a drive shaft driving the knife, in particular is a positive shaft/hub connection between a shaft driving the second cutting element and a hub body holding the second cutting element, in particular a splined-shaft connection or a key/groove connection.

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