Scraper with an easily replaceable scraper element

Abstract

A scraper (18) for a conveyor belt (12), a scraper module (26, 126) therefor, a belt conveyor (10) herewith and a method for exchanging a scraper element (42) on a scraper (18) or belt conveyor (10) are described. The scraper (18) according to the invention includes a system carrier (24) with at least one scraper module (26, 126). The scraper module (26, 126) has a base element (32) arranged on the system carrier (24) and a scraper element (42) for abutting against the conveyor belt (12). In order to make it possible to change the scraper element (42) particularly easily, the scraper element (42) is rotatably attached with a rotational coupling about a rotational axis (64) with respect to the base element (32). The rotational coupling is configured such that, in a rotational position of the scraper element (42) within a fixed angular range (68b), the scraper element (42) is firmly coupled to the base element (32) in the direction of the rotational axis (64). In a rotational position of the scraper element (42) within a release angular range (68a), the scraper element (42) can be detached from the base element (32) in the direction of the rotational axis (64).

Description

[0001] Description

[0002] Wiper with easily replaceable wiper element

[0003] The invention relates to a scraper for a conveyor belt, a scraper module therefor, a belt conveyor equipped therewith and a method for changing a scraper element.

[0004] The use of scrapers is common for conveyor belts used to convey a wide variety of materials. By applying a scraper element to the moving conveyor belt, any material adhering to it is scraped off. Known scraper systems feature a system carrier aligned transversely to the direction of travel of the conveyor belt, on which a plurality of scraper modules with scraper elements are located.

[0005] DE 10 2013 006 821 Ai describes a belt scraper system consisting of modules for the return section of conveyor belts. A system carrier is arranged transversely to the running direction of the conveyor belt. Several scraper modules are mounted next to each other on the system carrier. The scraper modules each carry a scraper blade that rests against the belt in a peeling manner. WO 95 / 19310 describes a device for scraping contaminants from

[0006] Conveyor belts in conveyor systems. A system carrier is attached to a support frame for the belt. A scraper element with a scraper blade attached to a slat support is arranged such that, in the ready-to-use position, it rests against the belt in a peeling manner. The scraper element has a torsion spring joint on which the slat support is pivoted about a horizontal pivot axis and spring-loaded. This allows it to pivot away when encountering obstacles firmly attached to the belt and then return to the ready-to-use position. The slat support is pivotally mounted by means of a pivot bearing with a limited angle of rotation, allowing the scraper blade resting on the belt to adapt to the contour of the belt through automatic rotation.

[0007] The scraper elements attached to the conveyor belt during operation are subject to significant wear and tear and must be replaced regularly. The objective is to propose a scraper, a scraper module for this purpose, a belt conveyor incorporating this, and a method for replacing a scraper element on a scraper that enables easy replacement of the scraper elements.

[0008] The object is achieved by a scraper according to claim 1, a scraper module therefor according to claim 13, a belt conveyor according to claim 14 and a method according to claim 15. Dependent claims relate to advantageous embodiments of the invention.

[0009] The scraper according to the invention has at least one scraper module, preferably a plurality of scraper modules, on a system carrier. Each scraper module comprises at least one base element arranged on the system carrier and a scraper element provided for contact with the conveyor belt. The scraper element can, for example, be a scraper block made of a flexible material, in particular if the scraper is provided as a pre-scraper, i.e. for arrangement in the region of a deflection of the conveyor belt. The scraper can preferably be arranged in the return region of the conveyor belt. More preferably, the scraper element has a scraping edge, particularly preferably made of metal, e.g., hard metal. The scraper element can preferably contact the conveyor belt in a skiving manner.

[0010] The base element of the wiper module can be attached to the system carrier in various ways and is preferably detachable. It is particularly preferably attached to the system carrier by means of a clamp.

[0011] According to the invention, the wiper element is attached relative to the base element by means of a rotary coupling such that it can rotate about a rotational axis. The rotary coupling is designed such that a different coupling results depending on the rotational position of the wiper element with respect to the rotational axis: In a rotational position which lies within an angular range which is referred to here as the fixed angle range, the wiper element is firmly coupled to the rest of the wiper module, i.e. in particular to the base element, with respect to a movement in the direction of the rotational axis, whereas in a rotational position within an angular range which is referred to here as the release angle range, it can be released from the rest of the wiper module, i.e. in particular from the base element, in the direction of the rotational axis.

[0012] The rotary coupling thus ensures that the scraper element can be rotated around the axis of rotation, so that alignment relative to the belt surface is possible and thus, during operation, the scraper element has a good contact with the conveyor belt and can follow the shape of the conveyor belt - for example, if it is slightly sagging.

[0013] The rotary coupling also ensures a fixed coupling in the fixed angle range with respect to longitudinal movement in the direction of the rotation axis. This means that in a rotational position within the fixed angle range, the wiper element can be rotated but cannot be detached from the base element. However, when the wiper element is rotated so that it assumes a rotational position within the release angle range, the rotary coupling releases the wiper element, allowing it to be removed, preferably in the direction of the rotation axis, for example, for servicing purposes.

[0014] The fixed angle range and the release angle range can preferably be selected such that the scraper element is always located within the fixed angle range during operation, i.e., when the scraper element is in contact with the conveyor belt, and there is sufficient distance from the release angle range so that this is not reached with sufficient certainty during operation, i.e., rotation of the scraper element into the release angle range is prevented by the contact with the conveyor belt. For example, the fixed angle range can be selected such that a horizontal alignment of the scraper element or an alignment of the scraper element parallel to the system carrier lies within the fixed angle range, preferably at least substantially centrally.This position can be assumed to be the center position, with the fixed angle range extending from the center position preferably over at least + / - 30°, more preferably over at least + / - 40°, and particularly preferably over at least + / - 60°. Thus, the release angle range particularly preferably only begins at a significant rotation about the rotation axis of, for example, 90° + / - 20°, so that the fixed coupling is always guaranteed in all commonly expected operating positions.

[0015] On the other hand, the wiper element can be easily removed from the base element and thus from the system carrier for maintenance purposes by simply rotating it around the rotation axis until the release angle range is reached. The wiper element can then be removed preferentially in the direction of the rotation axis without having to loosen any other connections.

[0016] The result is a wiper with an easily replaceable wiper element, which can be implemented with a very simple design. The ability to rotate around the axis of rotation is used in two ways: firstly, to align the wiper element during operation and secondly, to release the wiper element when it needs to be replaced. Preferably, the rotation of the wiper element can be done manually and without tools.

[0017] To change, i.e., for example, replacing a worn scraper element with a new one, it is sufficient to rotate the old scraper element into the release angle range (which may require first moving the system carrier into a position where the scraper element is sufficiently spaced from the conveyor belt to allow rotation). The scraper element can then be detached from the base element, and a new scraper element positioned within the release angle range can be attached to the base element, e.g., plugged in, and then rotated into a rotational position within the fixed angle range for locking.

[0018] The rotary coupling can be implemented in various ways to fulfill the function according to the invention. According to a preferred embodiment, it has an engagement element and an insertion opening therefor, which are designed such that the engagement element can be guided through the insertion opening in a first rotational position, which lies within the release angle range, and the engagement element can be locked to the insertion opening in a second rotational position, which lies within the fixed angle range. The insertion opening and its edge can be part of the base element or attached to it, and the engagement element can be provided on the side of the wiper element, or vice versa.

[0019] Particularly preferably, the engagement element can be arranged on a shaft that can be inserted into an insertion sleeve, wherein the insertion opening is formed within the insertion sleeve. A border of the insertion opening can be designed to protrude inwards into the insertion sleeve. Preferably, the shaft is connected to the stripping element, for example, fixedly and immovably attached relative to it, while the insertion sleeve is fastened to the base element. The rotatability of the stripping element is preferably ensured by the rotatability of the shaft within the insertion sleeve. Preferably, the shaft and / or the insertion sleeve and particularly preferably also the axis of rotation can extend at least substantially at right angles to a stripping edge of the stripping element, or at least at an angle d of more than 45 0 , preferably 6o° or greater.

[0020] Preferably, the rotation axis is also arranged at least substantially perpendicular to the system carrier, or at least at an angle ß of more than 60°. Thus, when viewed from above or from below, the rotation axis preferably extends at least substantially parallel to the running direction of the conveyor belt. Viewed from the side, i.e., horizontally and transversely to the running direction of the conveyor belt, the rotation axis, in preferred embodiments, can form a relatively small angle g with the running direction of the conveyor belt, for example, 0 - 35 0 However, alternative advantageous designs are also conceivable in which the axis of rotation is set much steeper relative to the running direction of the conveyor belt, ie at larger angles g.

[0021] According to a preferred embodiment, the rotation of the scraper element about the axis of rotation is slightly dampened or provided with a targeted stiffness so that no free rotation occurs when, for example, only gravitational forces act on the scraper element. On the other hand, the rotary coupling is so smooth that when forces such as those caused by the scraper element being in contact with the conveyor belt act, free rotation and alignment of the scraper element is possible. The targeted damping or stiffness makes installation of the scraper element easier because it makes it possible to specify a desired orientation of the scraper element, for example by manual rotation, without this changing undesirably. In the preferred design of the rotary coupling with a shaft that can be inserted into a plug-in sleeve, damping can be provided, for example.are carried out by means of a friction element which is designed to rest on the shaft and / or an inner side of the insertion sleeve in order to dampen a relative movement - in particular rotation - between the shaft and the insertion sleeve.

[0022] Furthermore, in the preferred case of the rotary coupling being designed with a shaft and an insert sleeve, a sealing element can preferably be provided for sealing between the shaft and an inner side of the insert sleeve to prevent the ingress of contaminants. The sealing element can preferably completely surround the shaft, e.g., as an O-ring. In particular, the sealing element can also be used to achieve the desired damping of the relative movement between the shaft and the insert sleeve.

[0023] According to a further development of the invention, the scraper module can have a joint by means of which the scraper element can be pivoted relative to the system carrier. Preferably, a pivot axis of the joint can be aligned at least substantially parallel to the system carrier. Furthermore, it is preferred that a pivot axis of the joint is aligned at least substantially perpendicular to the axis of rotation of the rotary coupling, or at least at an angle of at least 60° thereto. By pivoting the scraper element in the joint, a variable contact with the conveyor belt can preferably be achieved; particularly preferred is the possibility of pivoting the scraper element away from the belt surface by means of a pivoting movement in the joint in order to allow obstacles to pass.

[0024] Preferably, a spring element can be provided to apply a contact force to the scraper element in the direction of the conveyor belt. In this way, a resilient contact of the scraper element with the conveyor belt can be achieved. For this purpose, the use of any type of spring element is possible, e.g. as a torsion spring, spiral spring, tension or compression spring, etc. The use of a rubber torsion spring is particularly preferred, which is more preferably arranged in the joint. According to an advantageous embodiment, a stop for the pivoting movement of the scraper element is provided in the joint. This makes it possible, in particular, to limit the movement of the scraper element in the direction of the conveyor belt. The stop is preferably positioned such that, in the stop position, a pretension still exists towards the surface of the conveyor belt.

[0025] Preferably, the wiper element can be connected to the joint via a wiper arm, wherein the rotary coupling is formed on the wiper arm.

[0026] The scraper module according to the invention according to claim 13 is provided as part of the described scraper and comprises at least the base element, the scraper element, and the rotary coupling. When the scraper is used on a belt conveyor according to the invention according to claim 14, the system carrier is aligned transversely to the conveyor belt, and the scraper element—or preferably a plurality of scraper elements—rests against the conveyor belt.

[0027] Embodiments of the invention are described in more detail below with reference to the drawings. In the drawings:

[0028] Fig. 1, 2 perspective views of a part of a belt conveyor with a conveyor belt and a scraper according to a first embodiment;

[0029] Fig. 1a is an enlarged perspective view of a holder from Fig. 1;

[0030] Fig. 3 is a side view of the scraper from Fig. 1, 2;

[0031] Fig. 4, 5 a scraper module of the scraper from Fig. 1-3 in plan view and in partially sectioned side view;

[0032] Fig. 6 shows a cross section through the wiper module from Fig. 5 along the line A..A;

[0033] Fig. 7 is a perspective view of the wiper module from Fig. 4, 5 with the wiper element removed;

[0034] Fig. 8a-8e are perspective views of different positions of parts of the wiper according to the first embodiment during removal of the system carrier; and

[0035] Fig. 9a-9c perspective views of the wiper according to the first embodiment when using a pull-out aid

[0036] Fig. 10 is a cross-sectional view along line B..B of Fig. 8b;

[0037] Fig. li is a perspective view of part of a belt conveyor with a conveyor belt and a scraper according to a second embodiment;

[0038] Fig. 12 is a plan view of a system carrier of the wiper from Fig. n;

[0039] Fig. 13 is a side view of the scraper from Fig. 11, 12;

[0040] Fig. 14 is a view analogous to Fig. 10 for the scraper from Fig. 11 - 13 according to the second embodiment.

[0041] Fig. 1, Fig. 2 show, for a first embodiment, perspective views of part of a belt conveyor 10 with a conveyor belt 12 that is deflected at a deflection pulley 14. A shaft of the deflection pulley is mounted on a belt frame 16, of which only parts are shown schematically here.

[0042] On the belt conveyor 10, a scraper 18 with a plurality of scraper modules 26 is provided with a system carrier 24 and a holder 20 and counter holder 22 for attachment to the belt frame 16.

[0043] The holder 20 and the counter holder 22 each have an attachment part that is fastened to the belt frame 16 or is part of the belt frame 16, here in the form of attachment plates 28. A holding element in the form of a holding plate 30 is attached to each of the attachment plates 28.

[0044] In the embodiment shown, the system carrier 24 is a tube with a continuous round cross-section. The retaining plates 30 each have round recesses with plastic sliding bushings 33 inserted therein, in which the system carrier 24 is rotatably mounted.

[0045] Fig. 3 shows a side view of two stripper modules 26. The stripper modules 26 each comprise a base element 32, which is releasably attached to the system carrier 24 in a clamping bracket 34. A stripper arm 36 is pivotably mounted on the base element 32 about a pivot axis 38. A stripper element holder 40 with a stripper element 42 is arranged at each end of the stripper arm 36.

[0046] As can be seen, for example, from Fig. 2, several scraper modules 26 are arranged side by side on the system carrier 24. The system carrier 24 extends in the direction of the width of the conveyor belt 12, i.e., transversely to its running direction. In the first embodiment, scraper modules 26 arranged side by side each have alternating shorter and longer scraper arms 36, so that the scraper elements 42 are arranged in two staggered rows, wherein, viewed in the running direction of the conveyor belt, there is always a slight overlap between the scraper elements 42 of the two rows. The scraper modules 26 are positioned side by side such that the rows extend over at least substantially the entire width of the conveyor belt 12.

[0047] During operation of the belt conveyor 10 and the scraper 18, the edges of the scraper elements 42 rest on the surface of the conveyor belt 12 in a peeling manner, as shown in Fig. 3, in the example shown in the return area of ​​the conveyor belt 12. The scraper elements 42 are pressed resiliently against the surface of the conveyor belt 12. Contamination and adhering material are thus scraped off the moving conveyor belt 12 by the scraper elements 42.

[0048] One of the wiper modules 26 is shown in more detail in Fig. 4 and 5. As shown there, a joint 44 is provided between the base element 32 and the wiper arm 36, so that the wiper arm 36 can pivot about a pivot axis 38. As shown, the joint 44 comprises a bracket 46 that surrounds the base element 32.

[0049] A rubber torsion spring (not shown) acts inside the joint 44 and applies a torque to the wiper arm 36.

[0050] A protruding tab is provided on the base element 32 as a stop 48. In a stop position, a portion of the bracket 46 rests against the stop 48, so that the wiper arm 36 can no longer pivot about the pivot axis 38. The rubber torsion spring is designed to urge the wiper arm 36 toward the stop, with a preload 48 of the spring prevailing in the stop position shown in Fig. 5.

[0051] Due to the action of the respective springs of the scraper modules 26, the scraper elements 42 are pressed against the surface of the conveyor belt 12, but can deflect against the action of the spring by pivoting in the joints 44 when corresponding forces act during operation, e.g., due to stationary belt damage, elevations, etc. on the surface of the conveyor belt 12, by a corresponding pivoting movement of the scraper arm 36 about the pivot axis 38. A preload of the entire scraper 18, with which the entirety of the scraper elements 42 is pressed against the conveyor belt 12, is predetermined by specifying a rotational position of the system carrier 24. For this purpose, a tensioning device 50 is provided on the holder 20 between the holding plate 30 and the system carrier 24. Fig. 1a shows the holder 20 in an enlarged view.A clamping ring attached to the system carrier 24 has a clamping arm 54 projecting radially from the system carrier 24, which can be clamped by means of a clamping screw 56 relative to a fixture fixedly attached to the holding plate 30. By adjusting the clamping screw 56, the system carrier 24 can be rotated and a preload of the springs of the wiper modules 26 can be adjusted.

[0052] As further shown in Fig. 1, ta, a plate-shaped support element 80 is also attached to the mounting plate 28 of the holder 20, which in the embodiment shown is arranged between the mounting plate 28 and the holding plate 30. The shape and function of the support element 80 will be explained in more detail later with reference to Figs. 8a-8d and Fig. 10.

[0053] During operation of the scraper 18, the scraper elements 42 are subject to continuous wear, necessitating regular inspection and maintenance. The scraper 18 is designed for particularly simple maintenance with regard to its attachment to the belt frame 16 and with regard to the attachment of the scraper elements 42 to the scraper modules 26. As is particularly clear from Fig. 4, Fig. 5, Fig. 7, the scraper arm 36 comprises two elements that are detachably fastened to one another, namely a shaft 58 attached to the scraper element holder 40 and a sleeve 60 connected to the base element 32, namely fastened to the bracket 46 of the joint 44. The shaft 58 is inserted into the sleeve 60 (Fig. 5) and secured by means of a rotary lock 62 in the direction of a longitudinal axis 64 of the scraper arm 36.

[0054] The longitudinal axis 64 extends in the embodiment shown, as can be seen from Fig. 2, Fig. 3, in a vertical view parallel to the running direction of the conveyor belt 12 and thus also at right angles, ie at an angle ß of 90° (see Fig. 8e) to the longitudinal axis of the system carrier 24. In a horizontal view from the side (Fig. 3), the longitudinal axis 64 extends at an angle g of approximately 9 0 to the running direction of the conveyor belt 12. Furthermore, the longitudinal axis 64 in the embodiment shown is perpendicular, ie aligned at an angle d of 90° to the contact edge of the scraper element 42 (see Fig. 4).

[0055] The shaft 58 is freely rotatable within the sleeve 60 about the longitudinal axis 64, which is why the longitudinal axis 64 is also referred to as the axis of rotation. However, a sealing ring 66 is provided, which, on the one hand, seals the interior of the sleeve 60 against the shaft 58 and, on the other hand, creates a certain stiffness in the movement of the shaft 58 relative to the sleeve 60 due to friction caused by the contact with the inside of the sleeve 60.

[0056] The rotary lock 62 comprises, on the sleeve 60 side, an elongated window 62a arranged inside with a rim that projects into the interior of the sleeve 60 and, on the shaft 58 side, an elongated, plate-shaped engagement element 62b that is fixedly attached to an extension 63 of smaller diameter at the end of the shaft 58.

[0057] As can be seen in particular from the cross-sectional view in Fig. 6, the engagement element 62b and the window 62a are shaped such that the engagement element 62b can be inserted through the window 62a in the direction of the longitudinal axis 64 when aligned parallel to the window 62a (dashed illustration), while it is locked to the edge of the window 62a in a position rotated relative to the parallel alignment as shown (solid line).

[0058] Consequently, with regard to the fixing of the shaft 58 to the sleeve 60 in the axial direction of the longitudinal axis 64, there is a dependence on the rotational position:

[0059] When the engagement element 62b is positioned parallel to the window 62a (dashed line), the shaft 58 with the wiper element holder 40 and wiper element 42 attached thereto is in a position within a release angle range 68a. When rotated in the release angle range, the rotary lock 62 is released and the shaft 58 can be freely displaced in the longitudinal direction relative to the sleeve 60.

[0060] Upon further rotation of the shaft 58 relative to the sleeve 60, the ends of the engagement element 62b engage behind the edge of the window 62a, so that the shaft 58 is fixed longitudinally relative to the sleeve 60. The corresponding rotational positions of the shaft 58 lie within a fixed angle range 68b in which the rotary lock 62 is locked.

[0061] As shown, the release angle range 68a is centered around the rotational position shown in dashed lines in Fig. 6, in which the front edge of the scraper element 42 intended for contact with the conveyor belt 12 is located at 90° to the longitudinal direction of the system carrier 24 and to the pivot axis 38 of the scraper module 26. The fixed angle range 68b, on the other hand, is centered around a rotational position which is rotated by 90° and shown in Fig. 6 with solid lines. In this rotational position, the edge of the scraper element 42 is aligned parallel to the longitudinal direction of the system carrier 24 and to the pivot axis 38 of the joint 44.

[0062] Due to the free rotation of the shaft 58 within the sleeve 60, the respective scraper element 42 can align itself with the contour of the conveyor belt 12 when in contact with the latter. In practice, this contour will not always be flat across the entire belt width, but will, for example, curve toward the edges. Due to the pressure, the scraper element holders 40 always position themselves so that the scraper elements 42 follow the shape of the conveyor belt 12.

[0063] However, in no operating situation is a rotational position reached that lies within the release angle range 68a. Thus, the rotary lock 62 always remains in the fixed angle range while the scraper element 42 is in contact with the conveyor belt 12, thus ensuring the attachment to the base element 32 of the respective scraper modules 26.

[0064] In order to enable work on the wiper 18 and the wiper modules 26, in particular to enable the replacement of the unit comprising the wiper element 42, the wiper element holder 40 and the shaft 26, the system carrier 42 with the wiper modules 26 attached to it can be released in a particularly simple manner and removed to the side, as explained below with regard to Figs. 8a to 8e.

[0065] For this purpose, a special attachment of the holding plate 30 to the attachment plate 28 is provided on the side of the holder 20 and a bearing of the system carrier 24 in the bearing bush 33 of the holding plate 30 on the side of the counter-holder 22 such that it is freely movable in its longitudinal direction.

[0066] As shown in Fig. 1a, the retaining plate 30 is secured to the mounting plate 28 of the bracket 20 by two plug connections 70 and a screw connection 72. The plug connections 70 are formed by two bolts arranged parallel and spaced apart on the mounting plate 28, which are precisely received in bores of the retaining plate 30. The plug connections 70 are detachable by pulling the retaining plate 30 off the mounting plate 28 in the longitudinal direction of the system carrier 24.

[0067] The screw connection 72 formed between the plug connections 70 comprises a screw aligned parallel to the bolts, with which the holding plate 30 is screwed to the mounting plate 28.

[0068] In an operating arrangement for operating the belt conveyor 10 and the scraper 18, the holding plate 30 is fixed to the mounting plate 28 by means of the screw connection 72.

[0069] During an interruption in operation, parts of the wiper 18 requiring maintenance can be removed by transferring the wiper 18 into an assembly arrangement. By loosening the screw connection 72, the retaining plate 30 can be detached from the mounting plate 28, and the plug connections 70a, 70b are subsequently released by pulling in the direction of the longitudinal axis of the system carrier 24. A handle 74 is provided for this purpose.

[0070] Starting from the operating arrangement, Fig. 8a first shows the loosening of the screw connection 72. Subsequently, the holding plate 30 is pulled off the mounting plate 28 together with the system carrier 24 in its longitudinal direction, whereby the plug connections 70a, 70b are released.

[0071] As already mentioned, the holder 20 comprises the support element 80 between the attachment plate 28 and the holding plate 30. The support element 80 has, as can be seen from Fig. 8b, a hook-shaped holding section 82 which extends in the direction of the system carrier 24 and partially encompasses it, forming a recess 86. The holding section 82 and the recess 86 have, as shown, an inner contour (round in this case) which corresponds to the outer contour (round in this case) of the system carrier 24. In the operating configuration, i.e. when the holding plate 30 is fastened to the attachment plate 28, the holding section 82 is arranged such that it does not touch the system carrier 24, but remains at a certain distance of a few millimeters from it. Above the holding section 82, the support element 80 has a cutout 84 through which the system carrier 24 extends.

[0072] In the assembly arrangement, i.e. after loosening the screw connection 72 and the plug connections 70a, 70b (Fig. 8b), the system carrier 24 sinks slightly and then rests on the holding section 82 of the support element 80 in the recess 86. After loosening the connection between the holding plate 30 and the attachment plate 28, the support element 80 takes over holding the system carrier 24. As shown, the support element 80 is fastened to the holding plate 28 and thus to the conveyor frame 16. As shown in Fig. 10, the holding section 82 at the recess 86 encompasses the system carrier 24 over a circumferential area a of approximately 135 0 and supports the system carrier 24 from below so that it does not fall down.

[0073] Subsequently, the system carrier 24 is pulled out in the direction of its longitudinal axis together with the retaining plate 30 and the clamping device 50 (Fig. 8b). The support element 82 supports the system carrier 24 so that it does not fall down. The ability of the system carrier 24 to slide in the bearing bush 33 of the counterholder 22 enables particularly easy removal.

[0074] The wiper modules 26 can pass through the mounting plate 28 and the support element 80, since the hook-shaped shape of the holding section 82 with the cutout 84, which only partially encompasses the system carrier 24, allows sufficient clearance so that when the system carrier 24 is pulled out, the wiper modules 26 can be moved into an extended position outside the belt area (Fig. 8d). The wiper modules 26 can thus be guided through a free area in the plane of the support element 80 and the mounting plate 28 without striking. The cutout 84 of the support element 80 forms part of the free area.

[0075] In the extended position, the wiper modules 26 are easily accessible and can be inspected and maintained. In particular, worn wiper elements 42 can be replaced by loosening the respective units consisting of wiper element 42, wiper element holder 40, and shaft 58 of the respective wiper module by rotating them around the rotation axis 64 as described above, separating them by pulling them off in the longitudinal direction, and then attaching new elements in the same way.

[0076] Inspection and maintenance of the wiper 18 is thus made particularly easy. In the illustrated embodiment, the system carrier 24, together with the wiper modules 26, can be pulled out sideways by loosening a single screw (screw connection 72). With the assistance of the support element 80, this can be performed by a single person.

[0077] If sufficient space is available to the side of the conveyor belt 12, the handling of the system carrier 24 during withdrawal can be further facilitated by using a withdrawal aid. For this purpose, as shown in Fig. 9a, an adapter 76 can first be attached to the side of the system carrier 24 and clamped or otherwise secured thereto. A tube can then be attached to the adapter 76, which serves as a withdrawal aid 78 and is attached as an extension of the system carrier 24. The withdrawal aid 78 allows the system carrier 24 to be handled particularly well, particularly in conjunction with the support on the holding section 82 of the support element 80.

[0078] Figs. 11-14 show a wiper 118 according to a second embodiment. The wiper 118 according to the second embodiment corresponds in numerous details to the wiper 18 according to the first embodiment, so only the differences will be explained in more detail below, and reference is made to the above description for the rest. The same reference numerals denote elements that are the same between the embodiments.

[0079] While in the wiper 18 according to the first embodiment, as described and illustrated, the wiper elements 42 are arranged in two rows, the wiper 118 according to the second embodiment comprises a single-row arrangement of wiper elements 42 on wiper modules 126 of equal length, which are arranged side by side on the system carrier 24.

[0080] As can be seen particularly from Fig. 12, the scraper edges of the scraper elements 42 are not aligned in the transverse direction of the conveyor belt 12 as in the first embodiment, but obliquely thereto at an angle which in the example shown is approximately 15 0 However, as in the first embodiment, the scraper arms 36 extend with their longitudinal axis 64 in the longitudinal direction of the conveyor belt 12, ie, as in the first embodiment, at an angle of ß of 90°.

[0081] On the scraper arms 36, the scraper elements 42 are arranged obliquely at an angle d of approximately 75 0 In this case, adjacent scraper modules e 126 are arranged so closely on the system carrier 24 that - viewed in the longitudinal direction of the conveyor belt 12 - there is a slight overlap of the scraper elements 42, thus resulting in a scraping effect across the entire belt width.

[0082] Otherwise, the scraper 118 according to the second embodiment is identical in structure and function to the scraper 18 according to the first embodiment, i.e., just as with the scraper 18, each scraper 118 comprises the base element 32, which is detachably attached to the system carrier 24 in the clamping holder 34, and the scraper arm 36, which is pivotally mounted about a pivot axis 38 and at the end of which a scraper element holder 40 with a scraper element 42 is arranged. The pre-tensioned torsion spring applies a torque so that during operation of the scraper 118, the scraping edges of the scraper elements 42 rest on the surface of the conveyor belt 12 in a scraping manner and are resiliently pressed against its surface 12 in order to scrape off dirt. In the case of stationary obstacles on the surface of the conveyor belt 12, the scraper elements 42 can deflect against the action of the spring by a pivoting movement of the scraper arm 36 about the pivot axis 38.

[0083] Fig. 13 shows a horizontal side view of the second embodiment, showing the angle g between the running direction of the conveyor belt 12 and the longitudinal axis 64. Depending on the arrangement and adjustment, the angle g can be, for example, between 0° and 20°; in the embodiment shown, the angle g is approximately 15°. 0 .

[0084] In the second embodiment, the wiper arm 36 also includes the shaft 58 attached to the wiper element holder 40, which is inserted into the sleeve 60 and can rotate therein about the longitudinal axis 64. The rotary lock 62 ensures that the shaft 58 can only be pulled out of or inserted into the sleeve 60 with the appropriate alignment, i.e., rotation from the normal position defined by the belt system.

Claims

Claims 1. Scraper for a conveyor belt (12), comprising a system carrier (24) with at least one scraper module (26, 126), wherein the scraper module (26, 126) has a base element (32) arranged on the system carrier (24) and a scraper element (42) for contacting the conveyor belt (12), wherein the scraper element (42) is rotatably mounted relative to the base element (32) about an axis of rotation (64) by means of a rotary coupling, wherein the rotary coupling is designed such that in a rotational position of the scraper element (42) within a fixed angular range (68b) the scraper element (42) is fixedly coupled to the base element (32) in the direction of the axis of rotation (64), and in a rotational position of the scraper element (42) within a release angular range (68a) the scraper element (42) is free in the direction of the The axis of rotation (64) is detachable from the base element (32).

2. Scraper according to claim 1, wherein - the rotary coupling has an insertion opening (62a) and an engagement element (62b) which are designed such that the engagement element (62b) can be passed through the insertion opening (62a) in a rotational position within the release angle range (68a) and the engagement element (62b) is locked at the insertion opening (62a) in a rotational position within the fixed angle range (68b).

3. Scraper according to claim 2, wherein the engagement element (62b) is arranged on a shaft (58) which can be inserted into an insertion sleeve (60), the insertion opening (62a) being formed within the insertion sleeve (60), - wherein a border of the insertion opening (62a) extends inwards into the insertion sleeve (6o) is trained above.

4. Scraper according to claim 3, wherein - the shaft (58) or the insertion sleeve (60) is firmly connected to the wiper element (42).

5. Scraper according to one of the preceding claims, wherein - the axis of rotation (64) has an angle (β) of more than 60° relative to the system carrier (24), preferably arranged at least substantially at right angles.

6. Wiper according to one of the preceding claims, wherein the fixed angle range (68b) extends from a central position at least over + / - 30°. 7- Wiper according to one of the preceding claims, wherein the rotary coupling has a shaft (58) which can be inserted into a plug-in sleeve (60), wherein a friction element (66) is provided for bearing against the shaft (58) and / or an inner side of the plug-in sleeve (60) in order to dampen a relative movement between shaft (58) and plug-in sleeve (60) against each other.

8. Wiper according to one of the preceding claims, wherein the rotary coupling has a shaft (58) which can be inserted into a plug-in sleeve (60), wherein a sealing element (66) is provided for sealing between the shaft (58) and an inside of the plug-in sleeve (60). 9- Wiper according to one of the preceding claims, wherein the wiper module (26, 126) has a joint (44), wherein the wiper element (42) is pivotable in the joint (44) relative to the system carrier (24). io. Scraper according to claim 9, wherein - a spring element is provided to act on the scraper element (42) in the direction of the conveyor belt (12).

11. Scraper according to claim 9 or 10, wherein - the wiper element (42) is connected to the joint (44) via a wiper arm (36), - wherein the rotary coupling is formed on the wiper arm (36).

12. Wiper according to one of claims 9 to 11, wherein a stop (48) is provided for the pivoting movement of the wiper element (42).

13. Wiper module (26, 126) for a wiper (18, 118) according to one of the preceding claims, comprising a base element (32) and a wiper element (42), wherein the wiper element (42) is rotatably mounted relative to the base element (32) by means of a rotary coupling about an axis of rotation (64), wherein the rotary coupling is designed such that in a rotational position of the wiper element (42) within a fixed angle range (68b) the wiper element (42) is fixedly coupled to the base element (32) with respect to a movement in the direction of the axis of rotation (64), and in a rotational position of the wiper element (42) within a release angle range (68a) the wiper element (42) is detachable from the base element (32) in the direction of the axis of rotation (64).

14. Belt conveyor, comprising a conveyor belt (12) and a scraper (18, 118) according to one of claims 1 to 12, wherein the system carrier (24) is aligned transversely to the conveyor belt (12) and the scraper element (42) rests against the conveyor belt.

15. Method for changing a scraper element (42) on a scraper (18, 118) according to one of claims 1 to 12 or on a belt conveyor (10) according to claim 14, wherein - the system carrier (24) is brought into a position in which the scraper element (42) has a sufficient distance from the conveyor belt (12) so that it is in a The rotation position is rotatable within the release angle range (68a), - the wiper element (42) is detached from the base element (32), - a new wiper element (42) is positioned on the base element (32) in a rotational position within the release angle range (68a) and rotated into a rotational position within the fixed angle range (68b).