EP4056287B1 - Screening device, especially an expansion shaft screening device - Google Patents

Description

The present invention relates to a screening device, in particular a tension wave screening device, with a screen box having at least two opposite side walls, with a plurality of cross members arranged between the side walls and running transversely to the longitudinal direction of the screen box, and at least one elastic sieve element which preferably rests on the cross members and is connected to the cross members.

With a sieving device of the aforementioned type, feed materials that are difficult to sieve, such as moist, sticky, clumping and/or caking materials, can be separated or sieved. In sieving devices known from practice, transverse supports which are movable relative to one another, in particular pivotable, are used, on which at least one sieve element rests and is fastened. Due to the tension and relaxation or compression of the sieve element initiated by the relative movements of the cross members, particularly high throwing accelerations of the feed material resting on the sieve element are achieved. This is due in particular to the fact that the sieve element connected to the cross members is elastically deformed by the regular movement of the cross members, for example due to the cross members swinging relative to one another, and is thus caused to deflect or oscillate relative to the sieve box.

In this context, various options for attaching the sieve elements to the cross members are known from practice. One possibility is to provide a terminal strip in the edge area of adjacent screen elements that overlaps the edge areas and is then screwed and/or clamped to the associated cross member.

The disadvantage of this fastening solution is, first of all, that the terminal strip used protrudes from the top of the sieve element or from a sieve surface of the sieve element and therefore represents an obstacle to the particle transport during the sieving process. The particles to be screened can build up in the area of the terminal strip and have a detrimental effect on the particle or conveying flow. In addition, fastening elements protruding on the top are subject to increased wear, especially when screening fine and/or moist and/or abrasive materials, which requires replacement Sieve elements difficult. Furthermore, due to the screw connections for fastening the sieve base, the assembly and maintenance effort increases considerably, as the use of conventional wrenches becomes virtually impossible over time due to the wear of the screw heads or cap nuts caused by material flowing past.

In order to achieve an efficient screening result, it is also necessary to reliably seal the screening area from the environment. Especially when sieving the difficult-to-screen materials mentioned above, namely moist, fine and/or sticky substances, the problem is to ensure a reliable seal of the sieve space or the sieve element from the adjacent environment. In this context, the areas in which the sieve element delimits the sieve surface towards the side walls have proven to be particularly vulnerable. This is due in particular to the fact that gap areas form in the area of adjacent or abutting screen elements. These inevitably form weak points with regard to a reliable seal, since an enlargement of these gap areas is sometimes unavoidable due to the compression or stretching of the sieve elements during sieving operation.

In this context it is from the EP 2 926 916 A1 a screening device of the type mentioned is known. The sieving device disclosed here has a sieve box in which alternating rigid and movable cross members are provided, with sieve elements resting on the cross members. Each screen element is connected via a curved covering support to a rigid cross member on the one hand and a movable cross member on the other hand in order to achieve tensioning and/or relaxation of the screen covering as a result of a relative movement between the rigid and movable cross members during the screening process.

The use of curved covering supports according to the EP 2 926 916 A1 , which are additionally attached to the side walls and, in conjunction with the sieve elements, delimit the sieve surface from these side walls, the above-mentioned problem is solved with regard to a reliable seal at the joint areas. However, this construction is problematic for another reason. The covering carrier in the area of the movable cross members must be designed to be permanently elastic in order to enable the sieve element to be sufficiently tensioned. If this is not the case, there will be a lot of wear and tear. a strong localized mechanical stress on the sieve element, which in turn is associated with a significant reduction in usage time and an increased replacement frequency.

In addition to the susceptibility described above, which occurs in the joint or transition area of adjacent sieve elements, longitudinal edge sections of the sieve element that run along the longitudinal direction of the sieve box also have a high susceptibility to unwanted passage of sieve materials or an inadequate seal.

In this context, the one in the EP 2 926 916 A1 disclosed screening device is also inadequate. Here the screen linings are mounted on lining supports and are curved upwards at their lateral edge areas. The lateral sealing in the area of the longitudinal edge sections takes place via a cover strip running in the longitudinal direction of the screen box, which overlaps the screen covering on the top side and rests in a clamping manner on the top end of the screen elements.

The sealing via the cover strip is inadequate in that a reliable seal only occurs in the areas in which the cover strip rests directly in a clamping manner on the upper edge of the covering carrier, which then acts as a counter bearing to the cover strip. However, there is no abutment between the covering carriers, so that in this area in particular during sieving operation there is no continuous seal between the cover strip and the sieve element due to the relative movement or compression of the sieve element. This then also leads to the formation of a gap in the area of the cover strip, especially when the sieve element is compressed, as a result of which material to be sieved can then escape from the sieve area and enter the environment, accompanied by reduced sieving efficiency and the need for frequent cleaning of the sieve device.

The US 2005/0274652 A1 relates to a screening device with cross members.

The US 2013/0126398 A1 relates to a screening device and a method for screening material.

The DE 10 2012 206 347 A1 relates to a screening device with a base frame that can be set in vibration.

Accordingly, the present invention has the task of providing a sieve device which enables a particularly reliable seal in the area of the longitudinal edge section of the sieve element.

The aforementioned object is achieved in a sieve device of the type described above in that at least one longitudinal edge section of the sieve element, which runs along the longitudinal direction of the sieve box, is clamped and thus held over its entire length by a sealing device.

According to the invention, in the sieve device of the aforementioned type, in departure from the previously discussed prior art, a clamping of the longitudinal edge section is provided over the entire length of the sieve element. For this purpose, an appropriately designed sealing device is used, which ensures that the sieve element is clamped in the longitudinal edge section not only over a limited area, for example in the area of the cross members, but is tightly clamped to the side wall over its entire length, in particular between adjacent cross members is held.

In this context, it is preferably provided that the sealing device has at least one lower, in particular strip-shaped, sealing means and at least one upper, in particular strip-shaped, sealing means, and that the longitudinal edge section of the sieve element is clamped in a clamping gap between the upper and the lower sealing means. Such a design of the sealing device provided according to the invention ensures that the longitudinal edge section of the sieve element is clamped flat over the entire length along the longitudinal direction of the sieve box and is therefore held particularly reliably relative to the side wall. Unlike the prior art, where a more punctual sealing occurs, the invention results in a secure seal over the length of the sieve element.

According to a particularly preferred embodiment of this aspect of the invention, it is provided that the sealing device is fastened to the side wall in such a way that the clamping gap is arranged above the cross members and in particular above deflection means arranged on the cross members and deflecting the sieve element along the longitudinal edge. In other words, the clamping gap, in which the longitudinal edge section of the sieve element is clamped, is arranged offset upwards relative to the cross members and, in particular, relative to the deflection means.

Accordingly, there is an area between the top of the cross members or the deflection means and the underside of the clamping gap in which the longitudinal edge section of the sieve element is not clamped or is essentially exposed. This makes it possible for the sealing device or the sealing means of the sealing device to grip and grip around the longitudinal edge section in a particularly reliable or sealing manner in order to ensure the advantages described above with regard to a reliable seal on the longitudinal edge in a particularly precise manner.

The sieve element is preferably guided upwards on its two opposite longitudinal edge sections which run in the longitudinal direction of the sieve box in order to achieve a trough or container-shaped design of the sieve surface. The sealing described above advantageously takes place in the area of the two longitudinal edge sections of the sieve element.

Preferably, the clamping gap is designed to extend in an angular range of greater than 5° to the plane of the side wall, in particular with the sealing elements being wedge-shaped on mutually facing sides and/or each having beveled clamping surfaces. The implementation of a bevelled clamping gap is associated with further improvements in terms of the sealing effect in the longitudinal edge section and thus further increases the screening efficiency.

With regard to the use of the deflection means, which can be designed in the form of an arc section and/or polygon for deflection, it is in particular provided that they are attached exclusively to rigid cross members. In contrast, preferably no deflection means are provided on movable cross members. This also takes into account the fact that rigid cross members are less susceptible to inadequate sealing compared to movable cross members. Accordingly, it would be comparatively disadvantageous, but in principle possible, to also provide deflection means on the movable cross members, since these would cause corresponding deformations in the longitudinal edge sections as a result of the movement of the movable cross member. This could then lead to undesirable gap formation and also increases material wear on the sieve element, the deflection means and the sealing means.

In a further preferred embodiment it is provided that at least two rigid cross members and at least one between the rigid cross members arranged movable cross members are provided that the sieve element is connected to the cross members in such a way that a relative movement of adjacent cross members results in a tensioning or relaxation of the sieve element, and that the sieve element is attached to at least three successive cross members.

Accordingly, it is possible and also preferred to provide the above-mentioned continuous clamping on the longitudinal edge in combination with a sieve element fastened to at least three successive cross members. In this context, it has been found within the scope of the present invention that such a combined measure results in a particularly sealed or efficient screening operation, since not only the main screen surface is reliably sealed due to the reduced gap formation, but also the longitudinal edge section due to the continuous clamping. In this respect, these two features complement each other, so to speak in a reinforcing or synergistic manner, to create a particularly sealed and efficient screening operation.

In connection with the creation of the invention, it has been recognized that by attaching the sieve element to at least three successive cross members, a significantly improved sealing effect is achieved in the context of the sieving operation compared to the prior art. This is due in particular to the fact that the sieve element extends in the longitudinal direction of the sieve box over at least three cross members and rests on them, which is associated with a reduction in the previously discussed weak points in the form of gap areas between sieve elements facing one another. The invention results in a reduction of the gap areas by at least 50% compared to the prior art. According to the invention, a large part of the sieve surface is formed without interruption, i.e. by the sieve surface of the sieve element itself, whereby the weak points are minimized accordingly and ultimately the seal is ensured. This ultimately results in a particularly efficient screening operation, since complete processing or screening of the feed material is achieved without significant losses due to materials getting into the environment through weak points.

The screening device preferably has several screening elements and/or several alternately arranged rigid and movable cross members. In particular is in In this context, it is provided that each sieve element is attached to at least three successive cross members. Alternatively, however, a single sieve element can also be provided, which extends over any number of rigid and movable cross members, preferably arranged alternately, and is firmly connected to them. In this embodiment, no sieve gap is ultimately provided, since only a single sieve element of the sieve device is provided.

In a preferred embodiment, at least one sieve element is attached to its opposite transverse edge sections, which run transversely to the longitudinal direction of the sieve box, to a rigid cross member and in the central area to at least one movable cross member arranged between the rigid cross members. This further improves the seal, since in the area above the movable cross member there is no interruption or no joint area between adjacent sieve elements and thus no weak points that affect the seal. In contrast, joint areas that are present on rigid cross members are less susceptible to failure due to the reduced relative movement and therefore generally have increased sealing compared to areas on movable cross members.

According to a further, preferred embodiment of the invention, it is provided that the sieve element has at least one fastening means running transversely to the longitudinal direction of the sieve box on its underside facing the cross members in the area of the transverse edge sections and in a central area for cooperation with a corresponding fastening means of the cross members. This inventive aspect is ultimately independent of the sieve device and therefore only affects the design of the sieve element with the fasteners on the underside. The sieve element can also have the fastening means only in the area of the transverse edge sections. In connection with the previously described embodiment, the sieve element also has fastening means in the central or middle region transverse to the longitudinal direction of the sieve box for cooperation with corresponding fastening means of the cross members.

Accordingly, within the scope of the present invention, a special sieve element is also proposed, which has specifically designed fastening means on the underside to ensure a reliable connection or attachment to at least three successive cross members.

In this respect, the sieve element provided according to the invention is designed in particular for use in a sieve device preferably according to the invention, in particular in a tension wave sieve device, in order to ensure fastening to at least three cross members arranged one behind the other in the longitudinal direction to ensure sealed sieving operation.

Accordingly, within the scope of the present invention, the use of a sieve element designed according to the invention in a sieve device preferably designed according to the invention, in particular a tension wave sieve device, is also proposed. In this way, the previously discussed advantages and special features can be realized accordingly.

In a further preferred embodiment it is provided that the sieve element is fastened to a cross member via at least one sieve element holder and that the connection or attachment of the sieve element holder to the cross member takes place via a latching device.

In the sieving device known from practice, such as that from EP 2 926 916 A1 , the sieve elements are attached to the associated cross beams via strip-shaped sieve element supports. The sieve element carriers are fastened along the cross member using a plurality of screws.

During the screening process, the screen element carriers are exposed to considerable mechanical stress. This can be observed in particular in the area of the movable cross members, through which the screen element carriers are constantly exposed to recurring compressive and stretching loads. In this context, the EP 2 926 916 A1 The proposed screw connection has proven to be particularly vulnerable, since the sieve element carrier made of plastic is ultimately fastened via a metal connection, which is formed by the screw or a reinforcement of the sieve element carrier on the one hand and the cross member on the other hand, accompanied by an increased wear effect on the cross member , in contrast to the sieve element carrier, cannot be replaced or can only be replaced with increased effort.

In addition, in addition to the increased wear, replacing screwed screen element carriers is time-consuming and therefore not easy to maintain, since the screws along the entire length of the screen element carrier must first be loosened and then refastened. Furthermore, it should be noted that in practice the use of different sieve elements is also associated with differently designed sieve element carriers. If, for example, a screening device is transferred from operation as a tension-shaft screening device to a throwing screen operation with system screens, other screening elements are usually used for this purpose, which in turn are also attached to the cross beams with correspondingly differently designed screen element supports. Due to the connection of the sieve element carriers by means of screws, the previously discussed disadvantages in relation to complex replacement are also significant in this context.

A locking device ensures a simple and therefore time- and cost-saving connection and attachment of the sieve element carrier to assigned cross members, which can be carried out by an operator largely without tools or with reduced use of tools. This ensures maintenance-friendly operation due to the efficient replacement of worn screen element carriers. At the same time, the advantages associated with the locking device are also transferred to the replacement of different or foreign screen element carriers, especially if correspondingly differently designed screen elements have to be used when changing the screening operation. This applies in particular to the case when a screening device conventionally designed as a tension shaft screening device is used in throwing screen operation with system coverings or is converted to this, which will be described in detail below

Preferably, the latching device has at least one latching projection of the screen element holder which projects in the direction of the cross member and at least one latching receptacle which extends on the cross member transversely to the longitudinal direction of the screen box and corresponds to the latching projection. Accordingly, the locking projection is preferably assigned to the sieve element holder.

In this context, it is particularly provided that the locking projection is arranged, preferably formed, on an underside of the screen element holder facing the cross member.

It should be noted that the sieve element holder proposed in the context of the present invention also represents an independent or inventive aspect of the invention, in particular in that a sieve element holder is proposed for use in a sieve device, in particular in a tension wave sieve device, which has a locking device with an associated cross member can be connected.

Accordingly, within the scope of the present invention, the use of a screen element holder designed according to the invention in a screening device preferably according to the invention, in particular a tension wave screening device, is also proposed. The sieve element holder acts as a fastening means for connecting the sieve element to the cross member, the sieve element holder in turn being fastened to the associated cross member in a latching manner or by means of a latching device, i.e. without screws and/or directly.

In particular, in connection with the latching connection, it is provided that the latching receptacle is provided on an upper side facing the sieve element holder of a, preferably C-profile, connecting holder which runs transversely to the longitudinal direction of the sieve box. The connection of the screen element holder to the associated cross member is thus carried out indirectly or via the connection holder, in the sense that a locking projection of the screen element holder engages in an assigned locking receptacle on the connection holder and can therefore be releasably fixed relative to the connection holder and ultimately to the cross member.

Preferably, the connection holder, which preferably consists of a rigid material, in particular a metal material, is connected directly to the cross member, in particular positively, non-positively and/or materially, for example welded. Other connection or fastening techniques for connecting, in particular, profile-shaped holders to, for example, metal supports are possible and are well known to those skilled in the art.

According to a particularly preferred embodiment, the sieve element holder preferably has at least one side bar for laterally reaching over the connecting holder. The side bar can preferably be connected in one piece to the sieve element holder or formed in one piece on it. In this way, a reliable fixation of the sieve element holder on the cross member can be achieved, accompanied by an efficient transfer of movement from the cross member to the sieve element and ultimately with a reliable and efficient sieving operation.

The sieve element holder preferably has on its upper side facing the sieve element at least one fastening means which runs transversely to the longitudinal direction of the sieve box and is preferably groove-shaped, the fastening means of the sieve element holder being intended to cooperate with a corresponding fastening means of the sieve element. In this context, it can be provided that the sieve element holder has at least two fastening means, in particular these fastening means being designed to run parallel to one another and transversely to the longitudinal direction in order to cooperate with corresponding fastening means which are preferably arranged on the underside of the sieve element. In this way, a gentle and/or efficient connection of the sieve element to the sieve element holders or the cross members is achieved.

Further features, advantages and possible applications of the present invention result from the following description of exemplary embodiments based on the drawing and the drawing itself. All described and/or illustrated features, individually or in any combination, form the subject of the present invention, regardless of their Summary in the claims or their relationship.

In this context, it is also understood that the features of the different embodiments of the invention described above and shown and described below with reference to the drawing can be combined with one another if necessary, even if this is not expressly mentioned in detail. Individual features can be used in isolation from other features described or shown to further develop the invention. The selected paragraph formatting does not prevent a combination of features from different paragraphs.

Fig. 1

eine perspektivische Darstellung einer schematisch dargestellten erfindungsgemäßen Siebvorrichtung,

Fig. 2

eine perspektivische Schnittdarstellung der in Fig. 1 schematisch dargestellten Siebvorrichtung,

Fig. 2a

eine ausschnittsweise Vergrößerung von Fig. 2 in einem Befestigungsbereich eines Siebelements an einem zugeordneten Siebelementträger,

Fig. 3

eine perspektivische Darstellung einer weiteren Ausführungsform einer schematisch dargestellten erfindungsgemäßen Siebvorrichtung,

Fig. 4

eine perspektivische Darstellung einer weiteren Ausführungsform einer schematisch dargestellten Siebvorrichtung ohne Siebelement und Dichteinrichtung,

Fig. 5

eine weitere perspektivische Darstellung der in Fig. 4 schematisch dargestellten Siebvorrichtung mit Siebelementen und Dichteinrichtung und

Fig. 6

eine perspektivische Darstellung einer weiteren Ausführungsform einer erfindungsgemäßen schematisch dargestellten Siebvorrichtung im Wurfbetrieb mit Systemsieben.

It shows:

Fig. 1

a perspective view of a schematically illustrated screening device according to the invention,

Fig. 2

a perspective sectional view of the in Fig. 1 schematically shown screening device,

Fig. 2a

a partial enlargement of Fig. 2 in a fastening area of a sieve element on an assigned sieve element carrier,

Fig. 3

a perspective view of a further embodiment of a schematically illustrated screening device according to the invention,

Fig. 4

a perspective view of a further embodiment of a schematically shown sieving device without a sieve element and sealing device,

Fig. 5

another perspective view of the in Fig. 4 schematically shown sieve device with sieve elements and sealing device and

Fig. 6

a perspective view of a further embodiment of a screening device according to the invention, shown schematically, in throwing operation with system screens.

In the figures, the same reference numbers are used for the same or similar parts, achieving corresponding properties and advantages, although repeated description is omitted for reasons of simplicity.

Fig. 1 shows a perspective view of a proposed screening device 1, which is in particular a tension wave screening device.

The sieving device 1 has a sieve box 2, which comprises two opposite, mutually parallel side walls 3. The sieve box 2 has a longitudinal extension L.

In this context, the longitudinal extent L preferably refers to a longitudinal extent or longitudinal extension of the side walls 3. The longitudinal direction L is aligned parallel to the side walls 3.

It should be noted that the longitudinal direction L is not associated with a restriction with regard to the shape of the sieve box 2 or the side walls 3, for example in that they must be elongated or elongated.

Alternatively or additionally, the longitudinal direction L can also relate to a conveying direction of the material to be screened. This is particularly the case when the sieve box 2 is not placed horizontally, but rather diagonally on a surface or floor. The inclined arrangement is often used in practice in order to realize a flow of the sieved material, in particular due to gravity, as part of the sieving process and thus to ensure a continuous supply or removal of the material to be sieved along the sieve surface.

Alternatively or in addition to the inclined arrangement described above, the sieve box 2 can be mounted so that it can oscillate relative to the ground and/or be decoupled from the ground. For example, a spring-damper arrangement or at least one suspension and/or at least one damping can be arranged between the sieve box 2 and the substrate.

In the example shown, the side walls 3 are formed in one piece or in one piece. However, it goes without saying that one or both side walls 3 can be designed in several parts in the longitudinal direction L or can be composed of several wall segments.

The screening device 1 of the Fig. 1 and 2 has several rigid cross members 4 arranged between the side walls 3, in this case rigidly connecting the side walls 3, which is shown in the sectional view Fig. 2 is indicated. In addition to the rigid cross members 4, in particular several cross members 5 that are movable relative to the rigid cross members 4 are provided.

The movable cross members 5 can be driven by a motor to realize a preferably oscillating pivoting movement. For this purpose, the movable cross members 5 can be pivoted about a pivot axis, so that the movable cross beams 5 can carry out a pivoting back and forth movement on a circular arc section around the pivot axis, in particular in a positively guided manner.

In principle, however, it is also possible for the movable cross members 5 to be moved and/or driven translationally or linearly in the longitudinal direction L relative to the rigid cross members 4. Ultimately, it is in principle also possible to carry out a combination of pivoting and translational movement components in order to realize a relative movement of the movable cross members 5 relative to the rigid cross members 4. In this respect, the implementation of the invention is preferably not limited to a specific type of movement of the movable cross members 5, as long as a relative movement of movable cross members 5 to rigid cross members 4 is implemented.

As in particular based on Fig. 1 As can be seen, the sieve device 1 has a plurality of sieve elements 6, preferably made of an elastic material, which are connected to the rigid cross members 4 and the movable cross members 5 in such a way that when the movable cross members 5 are pivoted, these sieve elements 6 are tensioned and/or relaxed results. The sieve elements 6 are arranged one after the other or adjacent to one another in the longitudinal direction L. Furthermore, it is shown that the sieve elements 6 rest on the cross members 4, 5, so they preferably cover them in order to form a closed sieve surface. Adjacent sieve elements 6 can abut each other at the edges. An edge-side overlap is also possible, in particular in such a way that a sloping step results in the conveying direction.

As an alternative to a plurality of sieve elements 6, it is in principle possible to use just one sieve element 6, which then extends over all cross members 4, 5, as shown in Fig. 3 is shown.

According to the invention it is provided that the sieve elements 6 extend over their longitudinal edge sections R running along the longitudinal direction L of the sieve box 2 entire length are held clampingly by a sealing device 9, as in Fig. 1 is clarified.

The opposite longitudinal edge sections R of the sieve elements 6 are clamped and held by a sealing device 9 over the entire length of the sieve element 6. The sealing device 9 is located on a side wall 3 of the sieve box 2, with the sieve element 6 being deflected from its support plane via the rigid cross member 4 in the direction of the side wall 3 via deflection means 10. As a result, a trough-shaped sieve surface is ultimately formed, as is the case in particular in the embodiment according to Fig. 5 is shown.

Alternatively and/or additionally, the sieve element 6 can be guided in the direction of the side wall 3 via deflection means 10 provided on at least one movable cross member 5.

The screening device 1 in the embodiment according to Fig. 1 is ultimately characterized by a particularly efficient sealing of the sieve elements 6 in the area of the longitudinal edge sections R, in that a sealing device 9 in the longitudinal direction L enables continuous or uninterrupted clamping of the longitudinal edge sections R of the sieve elements 6 independently of the deflection means 10.

The sealing device 9 is formed over the entire length of the sieve elements 6 in the longitudinal direction L and is held or fastened to an associated side wall 3.

In addition, the sealing device 9 has at least one lower strip-shaped sealing means 9a and at least one upper strip-shaped sealing means 9b, the longitudinal edge sections R of the sieve elements 6 being clamped in a clamping gap formed between the sealing means 9a, 9b. At the in Fig. 1 In the embodiment shown, at least the upper sealant 9b is made up of several parts or is composed of several, here two, sealant segments. However, it goes without saying that one or each sealing means 9a, 9b can also be designed in one piece or continuously in one piece or without interruption in the longitudinal direction L.

Not shown, but preferably provided, is that the gap width of the clamping gap and / or the clamping force acting to achieve a sufficient frictional connection between the sealing means 9a, 9b and the longitudinal edge section R is preferably infinitely adjustable. As a result, sieve elements 6 with any thickness can be clamped securely and sealingly on their longitudinal edge sections R. Structurally, the preferably stepless adjustment takes place in particular via a threaded or other spindle-like device, which is preferably part of the sealing device 9 and/or is arranged on it.

As far as the design of the sieve elements 6 on their longitudinal edge sections R is concerned, they are guided upwards or in the direction of the side wall 3 via deflection means 10. In particular, each sieve element 6 is deflected upwards on both opposite longitudinal edge sections R via a deflection means 10 in order to realize a container- or trough-shaped sieve surface with regions guided upwards at the edge, as is particularly the case with reference to Fig. 3 is clarified.

This shows Fig. 1 that the sealing device 9 is fastened to the side wall 3 in such a way that the clamping gap is arranged above the cross members 4, 5 and above the deflection means 10 arranged on the cross members 4, 5.

The clamping gap is arranged or aligned in an angular range of greater than 5° to the plane of the associated side wall 3, in particular whereby the sealing elements 9a, 9b are wedge-shaped on mutually facing sides and/or each have beveled clamping surfaces. When in Fig. 1 In the exemplary embodiment shown, the clamping gap is inclined towards the associated side wall 3. However, other technical solutions are also possible here, according to which the clamping gap is inclined away from the side wall 3, as shown in particular Fig. 5 is clarified.

It is preferred that at least one sieve element 6 is attached to at least three successive cross members 4, 5, as shown by the sieve element 6 arranged on the left in the illustration Fig. 2 visible. The exact attachment of the sieve element 6 to the cross members 4, 5 will be discussed in detail later.

The screening device 1, in particular the embodiments of Fig. 1 to 2 , is ultimately characterized by the fact that at least one, preferably each, sieve element 6 is attached to three successive cross members 4, 5. This reduces gap or transition areas, such as those present in the area of adjacent sieve elements 6.

According to the invention, it is preferred that the connection of the sieve elements 6 takes place without fastening parts which protrude from the top or are accessible from the top of the sieve elements 6. In particular, the sieve surfaces of the individual, adjoining sieve elements 6 are preferably at least essentially aligned with one another on the upper side or, in the case of an overlap, merge into one another over a step. According to the invention, this is preferably achieved in that the sieve elements 6 are aligned with their transverse edge sections Q facing each other or abutting one another. This avoids areas that protrude on the top and negatively influence the flow of the material being screened. The same effect is also achieved if - as described above - adjacent sieve elements overlap at the edge, with a step sloping in the conveying direction.

As also based on Fig. 2 As can be seen, a rigid cross member 4 and a movable cross member 5 are alternately provided with respect to the longitudinal direction L. Each sieve element 6 is attached to opposite transverse edge sections Q, which run transversely to the longitudinal direction L of the sieve box 2, to a rigid cross member 4 and to at least one central region M on at least one movable cross member 5 arranged between the rigid cross members 4. In the example shown, each sieve element 6 is attached to a rigid cross member 4 at its transverse edge sections Q and to exactly one movable cross member 5 in the central area M. In principle or in principle technically possible, it is also possible for the sieve element 6 to be attached to two movable cross members 5 at the edge and to a rigid cross member 4 in the middle.

In this context, it should be noted that the term central area M is to be interpreted accordingly broadly, in the sense that ultimately every section running between the transverse edge sections Q and along the longitudinal direction L is included. In particular, the middle or central area M does not necessarily have to be exactly or at the same distances or when viewed in the longitudinal direction L. lie symmetrically between the transverse edge sections Q, but can also run at different distances, with respect to the longitudinal direction L, between the transverse edge sections Q.

Alternatively, as in particular based on Fig. 3 clarified, a sieve element 6 can also be attached to several central areas M with further cross members 4, 5, in particular to each central area M on a movable cross member 5. However, at least one additional attachment in a further central area M on a rigid cross member 4 be provided.

In the enlarged view according to Fig. 2a the attachment of a sieve element 6 to a movable cross member 5 is shown in a central area M. The sieve element 6 has on its underside facing the cross members 4, 5 in the central area M a row of two fastening means 7 running transversely to the longitudinal direction L of the sieve box 2, which are designed to cooperate with corresponding fastening means 8 which are arranged on the movable cross member 5. are trained. However, this does not necessarily have to be the case. A number of fasteners are generally sufficient.

It is a preferred feature of the in Fig. 2a illustrated embodiment, that the fastening means 7 of the sieve element 6 protrude from the underside of the sieve element 6 in the direction of the movable cross member 5 and are integrally formed on the underside of the sieve element 6. However, other technical solutions are also possible here, for example a connection of fastening means 7 to the sieve element 6, in particular via appropriately designed adapter elements or adapter strips, which are subsequently attached to the underside of the sieve element 6 after the actual sieve element 6 has been manufactured.

The aforementioned configuration ultimately enables the sieve element 6 to be easily attached without any fasteners on the top.

Like based on Fig. 2 Also visible, each sieve element 6 also has a fastening means 7 running transversely to the longitudinal direction L of the sieve box 2 in the area of the transverse edge sections Q. The fastening means 7 provided on the transverse edge sections Q can in principle, and preferably, be similar to the fastening means 7 in the area of the central region M can be formed, i.e. formed on the underside and/or in one piece. In principle, according to an embodiment not shown, a different design of the fastening means 7 compared to the central region M can also be realized on the transverse edge sections Q. In the area of the longitudinal edge sections R, no fastening means 7 on the underside are preferably provided in order to obtain a connection of the sieve element 6 that is as gap-free as possible on the edge to a sealing device which will be described in more detail below.

Preferably one, in particular each, fastening means 7 is strip-shaped and/or designed with a thickened or widened free end. In particular, this thickened free end is then designed to engage in a corresponding widened receptacle of the fastening means 8 of the cross members 4, 5 in order to realize a clamping and/or locking fixation of the sieve element 6 on the cross members 4, 5. The fastening means 7 are preferably designed to be elastic, in particular to enable them to snap into the associated fastening means 8 on the cross members 4, 5 at the top.

The following is based on the Figs. 2 and 2a Another aspect of the present invention is described.

So shows Fig. 2 that each sieve element 6 is fastened to the cross members 4, 5 via several sieve element holders 11, in the example shown via three sieve element holders 11. How this attachment is carried out in detail is explained below using the enlarged illustration Fig. 2a explained, in which the attachment of a sieve element 6 in the central area M to a movable cross member 5 is shown enlarged. It goes without saying that the following statements apply equally to the other fastening areas, i.e. to the transverse edge sections Q or to the rigid cross members 4.

According to this embodiment it is provided that the sieve element holder 11 is connected to the movable cross member 5 via a latching device 12.

The locking device 12 has a locking projection 13 projecting in the direction of the cross member 5 and a locking receptacle 14 on the cross member 5, which also runs transversely to the longitudinal direction L of the screen box 2. The locking projection 13 is preferably on the cross member 5 facing Underside of the sieve element holder 11 arranged, integrally formed in the example shown.

According to the embodiment shown, a connection holder 15 running transversely to the longitudinal direction L is also provided. The locking receptacle 14 is provided or formed on or in the connection holder 15. In the preferred exemplary embodiment, the connection holder 15 is profile-shaped, preferably as a C-profile with a slot on the top, the locking receptacle 14 being formed within the connection holder 15 and laterally limited by legs of the connection holder 15 projecting in the direction of the sieve element 6, preferably with the legs on their free ends are aligned facing each other, preferably bent towards each other, so that a rear grip is possible. As a result, the locking projection 13 can snap between the legs and ultimately into the locking receptacle 14.

The connection holder 15 consists of a rigid material, in particular a metal material, preferably steel, and is firmly connected to the cross member 5. In this regard, there are a variety of fastening options available, for example a detachable connection, in particular by means of screwing. Alternatively, however, an inseparable connection of the connection holder 15 to the cross member 5 can also be realized, for example by means of welding or gluing. Other fastening options, for example via a further snap connection and/or clamping, are also possible.

The sieve element holder 11, which in principle also has its own inventive significance, has two side strips 16 in the example shown, which preferably stand on the respective cross member 5, 6. The side strips 16 also extend transversely to the longitudinal direction L and surround the connection holder 15 on both sides. In the illustrated and preferred exemplary embodiment, the side strips 16 are integrally formed on the sieve element holder 11. However, other technical solutions are also possible here, for example a detachable connection of the side strips 16 to the sieve element holder 11.

The sieve element holder 11 as such is preferably made of or has a plastic material.

The sieve element holder 11 has on its upper side at least one fastening means 8, in the example shown, which runs transversely to the longitudinal direction L and which are designed to cooperate with the corresponding or complementary fastening means 7 of the sieve element 6. In this context, it is preferred if the fastening means 8 are designed as longitudinal grooves and, in particular, have a widened end region into which correspondingly designed, widened free ends of the fastening means 7 can engage and/or preferably snap in a clamping and/or locking manner.

The implementation of two fastening means 8 on the top of the sieve element holder 11 has the advantage that two adjacent sieve elements 6 can be fastened at the edge via a sieve element holder 11. With such a design of the sieve element holder 11, it can then also make sense to provide two corresponding fastening means 7 on the underside of the sieve element in the central area M in order to ensure a particularly good connection of the central area of the sieve element 6 to the associated cross member 4, 5, in particular to the movable one Cross member 5, available.

In Fig. 3 An embodiment is shown in which the sieve element 6 is fastened to a rigid cross member 4 in the transverse edge section Q and is fastened to movable cross members 5 in between in the central region M. Accordingly, according to this embodiment, the sieve element 6 can extend in the longitudinal direction over any number of cross members 4, 5, in particular over more than three cross members 4, 5, in the longitudinal direction L.

Based on Fig. 4 It is clarified how the deflection means 10 are designed and/or arranged for deflection of the sieve elements 6 on their longitudinal edge sections R.

In the context of the invention, it is preferred if the deflection means 10 are designed to be curved upwards in order to realize a corresponding upward deflection of the sieve elements 6 at their longitudinal edge sections R. Alternatively or in combination with the curved or arc-like design of the deflection means 10, a polygon-like shape can also be provided. Ultimately, the deflection means 10 serve to move the sieve element 6 out of the actual Sieve plane, which is provided by the cross members 4, 5, in the direction of the side walls 3, which preferably run at right angles to them.

The deflection means 10 are arranged in the area of the side walls 3 and, if necessary, attached to cross members 4, 5 or adjoin them. In the present case, 4 deflection means 10 are only provided on rigid cross members.

The deflection means 10 can only be attached to the cross members 4, 5, i.e. not to the side walls 3. The attachment of the deflection means 10 to the cross members 4, 5 can preferably be carried out in a latching and/or clamping manner. In this context, it is possible to use an analogous locking device 12, which was previously discussed in connection with the sieve element holder 11, to connect the deflection means 10 to the cross member 4 or 5. This makes it possible to achieve the advantages already discussed in relation to the sieve element holder 11. Alternatively or additionally, however, another type of fastening, for example screwing, can also be used to connect the deflection means 10 to the cross members 4, 5.

As also based on Fig. 4 As can be seen, a deflection means 10 adjoins one end of the sieve element holder 11. It is understood that when deflecting both longitudinal edge regions R of a sieve element 6, a deflection means 10 is arranged at each end of the sieve element holder 6 or adjoins it.

What is not shown is that at least one, preferably both, deflection means 10 can be formed in one piece with the sieve element holder 11. This results in a compact unit that is easy to assemble.

The deflection means 10 can, as is particularly the case in Fig. 5 can be seen, be arranged or aligned directly adjacent or contact-bound to the side walls 3. In this constellation, it is particularly possible for the sealing devices 9 or the corresponding sealing means 9a, 9b to be arranged offset above or upwards relative to the deflection means 10.

Equally, however, it is also possible for the deflection means 10 to be arranged inwardly offset relative to the side wall 3 or to be arranged relative to the side walls 3 to form an intermediate gap. This is preferably done in such a way that between the deflection means 10 and the Side walls 3, the lower sealing element 9a of the sealing device 9 can protrude into this intermediate gap. Such a constellation is particularly advantageous if the screening device 1 according to the invention is to be transferred from an operation as a tension wave screening device to another operation, in particular a throwing sieve operation with system sieves.

This is how it is based on Fig. 6 a further advantageous aspect of the present invention is discussed. In contrast to the previously discussed embodiments, the sieving device 1 according to the invention is shown here in a throwing sieve operation with system sieves or not in a tension wave sieve operation.

The throwing sieve operation with system sieves can be accompanied by the use of additional or different sieve elements 17, which are preferably designed to be inelastic or inflexible.

Usually, in throwing sieve operation with system sieves, there is no deflection at the longitudinal edge sections R, in which case it is preferred that the lower sealing means 9a of the sealing device 9 can function as a protective element for the side wall 3, and, particularly preferably, extends to the top of the sieve elements 17 . It goes without saying that the lower sealant 9a acts as a protective element not only for one but for both side walls 3 and/or protrudes up to the top of the sieve elements 17.

Accordingly, as part of the conversion from the tension-shaft sieving operation to the throwing sieve operation with system sieves, only the upper sealing means 9b as well as the preferably elastic sieve elements 6 and, if necessary, deflection means 10 are to be removed. In contrast, the lower sealant 9a remains on the screen box 2 and, as defined above, fulfills the function as a protective element or protective strip for the associated side wall 3.

Furthermore, with regard to the conversion to throwing sieve operation with system sieves, it should be noted that to connect the other or inflexible sieve elements 17 in throwing sieve operation with system sieves, correspondingly different or additional sieve element holders 18 are used, which also have the locking device 12.

Due to the locking device 12 provided according to the invention, the sieve element holders 11, which are used in particular for the tension shaft sieve operation, can be removed from the connecting holders 15 quickly or largely without tools. Subsequently, the other sieve element holders 18, which also preferably have a latching device 12 in the sense discussed above, are snapped onto the connecting holders 15 provided on the cross members 4, 5. The sieve elements 17 provided for the throwing sieve operation with system sieves can then be placed or clamped onto the sieve element holders 18.

List of reference symbols:

1

Sieving device

2

Sieve box

3

screen wall

4

rigid cross members

5

movable cross beams

6

Sieve element

7

Fasteners

8th

Fasteners

9

Sealing device

9a

bottom sealant

9b

top sealant

10

Deflection means

11

Sieve element holder

12

Rest facility

13

locking projection

14

snap-in recording

15

Connection holder

16

Sidebar

17

other sieve element

18

other sieve element holder

L

Longitudinal direction

M

central area

Q

Transverse edge section

R

Longitudinal edge section

Claims (5)

1. Screening device (1), in particular a tension shaft screening device, with a screening box (2) having at least two opposing side walls (3), with a plurality of transverse supports (4, 5) arranged between the side walls (3) and extending transversely to the longitudinal direction (L) of the screening box (2), and at least one elastic screening element (6) connected to the transverse supports (4, 5),
   characterized in that
   in that at least one longitudinal edge section (R) of the screening element (6) running in the longitudinal direction (L) of the sieve box (2) is clamped over its entire length by a sealing device (9) and held therewith.
2. Screening device according to claim 1, characterized in that the sealing device (9) has at least one lower, in particular strip-shaped, sealing means (9a) and at least one upper, in particular strip-shaped, sealing means (9b), and in that the longitudinal edge section (R) of the screening element (6) is clamped in a clamping gap between the upper and the lower sealing means (9a, 9b).
3. Screening device according to claim 1 or 2, characterized in that the sealing device (9) is fastened to the side wall (3) in such a way that the clamping gap is arranged above the transverse supports (4, 5) and, in particular, above deflecting means (10) arranged on the transverse supports (4, 5) and deflecting the screening element (6) on the longitudinal edge side.
4. Screening device according to one of the claims 1 to 3, characterized in that the deflecting means (10) are exclusively attached to rigid transverse supports (4).
5. Screening device according to one of the claims 1 to 4, characterized in that the clamping gap extends in an angular range of greater than 5 degrees relative to the plane of the side wall (3), in particular wherein the sealing elements (9a, 9b) are wedge-shaped on mutually facing sides and/or each have chamfered clamping surfaces.

Images