Abstract
A return roller is pivotally supported in a frame-fixed articulation region (20, 21) of a belt conveyor device having a transport belt. A pivot arm (30, 31) extends in a running direction (L) of the transport belt, orthogonal to a longitudinal axis (12) of the return roller, supporting it about the longitudinal axis. A pivot element (40) is spaced apart from the return roller in the running direction. A pivot bearing (22, 23) is arranged on the articulation region for mounting the pivot element for a pivoting movement of the pivot arm around a pivot axis between an operating position and an nonoperating position of the return roller. A bearing surface (24, 25), in a section perpendicular to the pivot axis, is formed as an open arc, with an opening (26, 27) having a center angle (φ) of less than 180°.
Claims
1. A device for pivotably supporting a return roller in a frame-fixed articulation region of a belt conveyor having a transport belt that circulates over the return roller in a running direction (L), the device comprising: a pivot arm that extends in the running direction, which is orthogonal to a longitudinal axis of the return roller, the pivot arm rotatably supporting the return roller about the longitudinal axis; a pivot element of the pivot arm that is spaced apart from the return roller in the running direction; a pivot bearing, arranged on the articulation region for mounting the pivot element, allowing a pivoting movement of the pivot arm between an operating position of the return roller and a nonoperating position of the return roller, about a pivot axis that is parallel to the longitudinal axis, wherein the pivot bearing has a bearing surface in the form of an open arc, in a section perpendicular to the pivot axis, an opening of which appears at a center angle (φ) of less than 180°; and a sliding body, formed on the pivot element, which, in a pivot position range containing the operating position, is rotatably guided on the bearing surface while fixed on the articulation region and which can be passed through the opening in the nonoperating position.
2. The device according to claim 1, further comprising: a passage channel for the sliding body extending from the opening to a free outlet that is formed in the articulation region.
3. The device according to claim 2, wherein the passage channel, starting from the opening, extends in a direction that is inclined at an acute angle toward the return roller, relative to an orthogonal straight line (G) connecting the longitudinal axis of the return roller and the pivot axis of the pivot element.
4. The device according to claim 1, wherein: the pivot arm has a first pivot arm and a second pivot arm which are arranged on both sides of the return roller; the pivot element has a first sliding body assigned to the first pivot arm and a second sliding body assigned to the second pivot arm; and the pivot bearing has a first pivot bearing accommodating the first sliding body and a second pivot bearing accommodating the second sliding body.
5. The device according to claim 4, wherein the pivot element has a supporting axis extending between the pivot arms, at the axial end regions of which the first and second sliding bodies are arranged, and the center axis of which forms the pivot axis.
6. The device according to claim 1, further comprising: a locking device for fixing the pivot arm in the operating position.
7. The device according to claim 6, wherein the locking device has a stop arranged on the pivot arm and a counter stop arranged on the frame-fixed articulation region.
8. The device according to claim 7, wherein at least one of the stop and the counter stop is adjustable.
9. The device according to claim 1, wherein: the sliding body has a cross section defined by a section perpendicular to the pivot axis by two arcs (K1, K2) having a common center point and equal radius (R) and two chords (S1, S2) that connect the respective closest ends of different arcs (K1, K2) to one another, wherein a center angle (α) of the two arcs (K1, K2) is smaller in each case than the center angle (φ) at which the opening appears.
10. The device according to claim 9, in which the chords are parallel to one another and of equal length.
11. The device according to claim 1, wherein the pivot arm is axially fixed.
12. The device according to claim 1, wherein: an association of the return roller and the frame-fixed articulation region is encoded by two mutually complementary engagement parts, a first of which is arranged on the pivot element and a second of which is arranged on the frame-fixed articulation region, the two engagement parts engaged with one another in an installed position.
13. The device according to claim 12, wherein one of the engagement parts is formed as a concave recess and the other engagement part is formed as a convex projection.
14. A belt conveyor device, comprising: a transport belt; and a device for supporting a return roller according to claim 1.
15. The belt transport device according to claim 14, wherein the transport belt is elastic.
Description
BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWING
[0031] In the following description the invention is explained by way of example with reference to the drawing. In the figures
[0032] FIG. 1 shows a perspective view of a device according to the invention attached to a framework of a frame, in which the return roller is arranged in the operating position,
[0033] FIG. 2 shows a region of the device shown in FIG. 1 without the first pivot arm,
[0034] FIG. 3 shows a view of the device shown in FIG. 1 from above,
[0035] FIG. 4 shows a view of a region of the device shown in FIG. 1 in the direction of the pivot axis without the first pivot arm,
[0036] FIG. 4a shows a side view of the sliding body from FIG. 4,
[0037] FIG. 4b shows a schematic side view of a region containing the bearing from FIG. 4,
[0038] FIG. 5 shows a view of the device shown in FIG. 1 in the direction of the pivot axis, in which the return roller is pivoted out of the operating position,
[0039] FIG. 6 shows a locking device of an embodiment of the device according to the invention in a section perpendicular to the pivot axis,
[0040] FIG. 7 shows a view from above of a further embodiment of a device according to the invention attached to a framework of a frame having engagement parts encoding the association of return roller and frame-fixed articulation region,
[0041] FIG. 8 shows a section along line A-A in FIG. 7,
[0042] FIG. 9 shows a perspective view of a device for supporting a return roller of the prior art.
DESCRIPTION OF THE EMBODIMENTS
[0043] FIG. 1 shows a perspective view of a device according to the invention attached to a frame 1 of a frame 2 of a belt conveyor device, in which a return roller 10 is arranged in the operating position. The framework 1 of the frame 2 has a first side arm 3 and a second side arm 4, which extend in a direction of travel L of a transport belt (not shown). A frame-fixed articulation region having a first region 20 and a second region 21 is formed on the frame 2. The first region 20 integrally formed with the first side arm 3 and the second region 21 is integrally formed with the second side arm 4. A first pivot bearing 22 is arranged on the first region 20. A second pivot bearing 23 is arranged on the second region 21.
[0044] At its axial ends 10a, 10b, the return roller 10 is rotatably supported about its longitudinal axis 12 on two pivot arms (first pivot arm 30 and second pivot arm 31) extending in the direction of travel L.
[0045] Spaced apart from the return roller 10 in the running direction L, a pivot element designed as a support axle 40 is arranged perpendicular to the running direction L. The support axle 40 is connected to the first and the second pivot arms 30, 31. The center axis of the support shaft 40 forms a pivot axis 44 for the pivoting movement of the first and second pivot arms 30, 31. A first and a second sliding body 41, 42 are arranged at the axial ends of the support axle 44. In FIG. 1, the first sliding body 41 is inserted into the first pivot bearing 22 and the second sliding body 42 is inserted into the second pivot bearing 23. The first and second sliding bodies 41, 42 are rotatably supported in the first and second pivot bearings 22, 23, respectively. This allows the return roller 10 to be pivoted around the pivot axis 44.
[0046] In the embodiment shown in FIG. 1, the first and the second pivot bearing 22, 23 are mirror-symmetrical with respect to a center plane extending perpendicularly to the pivot axis 44. With respect to this center plane, the first pivot arm 30 is mirror-symmetrical to the second pivot arm 31, and the first sliding body 41 is mirror-symmetrical to the second sliding body 42. Therefore, only the first pivot bearing 22 and the first sliding body 41 will be described in the following description.
[0047] FIGS. 2 and 4 show a perspective view and a view of a region of the device shown in FIG. 1 without the first pivot arm 30 in the direction of the pivot axis 44. FIG. 4a shows an enlarged view of the sliding body 41 from FIG. 4, and FIG. 4b schematically shows the bearing surface 24 from FIG. 4. The shape of the first pivot bearing 22 and the shape of the first sliding body 41 can be seen particularly clearly in the figures. The cross section of the first sliding body 41 is given in a section perpendicular to the pivot axis 44 by two arcs K1, K2 having the same radius R having a common center and two chords S1, S2 connecting the respective nearest ends of different arcs K1, K2 (see also FIG. 4a).
[0048] The bearing surface 24 of the first pivot bearing 22 is formed in a section perpendicular to the pivot axis 44 in the shape of an open arc whose opening 26 appears at a center angle of φ<180° (see FIG. 4b). The arcuate bearing surface 24 thus has a center angle θ>180°. The radius r of the arcuate bearing surface 24 corresponds to the radius R of the arcs K1, K2. The arcs K1, K2 each have a center angle α which is smaller than the center angle φ at which the first opening 26 appears, α<φ. The bearing surface 24 encloses the first sliding body 41 in such a way that the bearing surface 24 supports the sliding body 41 in a pivot position range containing the operating position of the return roller 10 in a rotationally movable but translationally fixed manner. The first sliding body 41 thus cannot be passed through the opening 26 in the pivot position range. Thus, in the pivot position range, the support axle 40 is fixed on the pivot bearings 22, 23 and cannot be removed from the pivot bearings 22, 23.
[0049] Due to the condition that the center angle α of the arcs K1, K2 is smaller than the center angle φ of the opening, the first sliding body 41 can be passed translationally through the opening 26 in the pivot position of the nonoperating position which is outside the pivot position range. In this nonoperating position, either the first arc K1 or the second arc K2 of the first sliding body 41 is arranged opposite to the first opening 26. In the embodiment shown in FIGS. 1 to 4, a passage channel 29 extends from the opening 26 to a free outlet 28. The passage 29 extends, starting from the opening 26, in a direction that is inclined toward the return roller 10 at an acute angle in relation to an orthogonal straight line G connecting the longitudinal axis 12 of the return roller 10 and the pivot axis 44 of the support axle 40. The passage channel 29 is dimensioned in such a way that the first sliding body 41 can be guided through it. The statements above also apply to the second pivot bearing 23 and the second sliding body 42. In the nonoperating position, the support axle 40 can be removed through the openings 26, 27. Thus, the return roller 10 can be removed from the frame 2 of the belt conveyor device.
[0050] In a device according to the invention, the pivot arm can be axially fixed. For this purpose, as shown in FIG. 3, the support axle 40 can have a radius in contact regions 43a, 43b adjacent to the first sliding body 41 and/or in contact regions 43c, 43d adjacent to the second sliding body 42 which is greater than the radius r of the first and second bearing surfaces 24, 25. A movement of the support axle 40 in the direction of the pivot axis 44 is thereby prevented.
[0051] FIG. 5 shows a view of the device shown in FIG. 1 in the direction of the pivot axis 44, in which the return roller 10 is pivoted out of the operating position. The position shown in FIG. 5 allows the attachment of a transport belt (not shown) circulating around the return roller 10 without the return roller 10 having to be removed from the frame 2. It is also apparent from FIG. 5 that pivoting the return roller 10 into the operating position causes the transport belt to be tensioned.
[0052] FIG. 6 shows a view of a device according to the invention having a locking device, by which the operating position of the return roller 10 is fixed, in a section perpendicular to the pivot axis 44. As shown in FIG. 6, the longitudinal axis 12 of the return roller 10 lies in the direction of gravity Z below the pivot axis 44. When a transport belt circulates around the return roller 10, the transport belt exerts a tensile force on the return roller 10, which is parallel to the running direction L. A torque thus acts on the return roller 10. In order to keep the return roller 10 in its operating position, a locking device is provided on the device. This locking device has a stop 51 provided on the second pivot arm 31 and a counter stop 52 arranged on the frame-fixed articulation region (second region 21). In the locking device shown in FIG. 6, the counter stop 52 is formed as a pin 52 extending in the direction of the longitudinal axis 12. The stop 51 arranged on the second pivot arm 31 is formed as a screw. The screw is an adjustable element which can be screwed further into or out of the second swing arm 31. The operating position of the return roller 10 can thus be adjusted. The locking device can additionally have a stop provided on the first pivot arm 30 and a counter stop provided on the first region 20. The stop can be formed as a screw and the counter stop can be formed as a pin. However, the locking device is not limited to the embodiment shown in FIG. 6. It is thus also conceivable that the counter stop is an adjustable element and the stop is fixed. Alternatively, both the stop and the counter stop can be designed as adjustable elements.
[0053] FIG. 7 is a view of another embodiment of a device according to the invention attached to a framework of a frame 2. The device shown in FIG. 7 has all the elements of the device shown in FIGS. 1 to 6. In addition, the device shown in FIG. 7 has engagement parts 60a, 60b, 61a, 61b coding for the association of return roller 10 and frame-fixed articulation region 20, 21. In the embodiment shown in FIG. 7, the support axle 40 has for this purpose two concave recesses 60a, 60b as a first engagement part, which are circumferential around the support axle 40 azimuthally. Complementary to this, a frame-fixed region of the frame 5 has two convex projections 61a, 61b as the second engagement part. In the installed position shown in FIGS. 7 and 8, the projections 61a, 61b are engaged with the recesses 60a, 60b. As can be seen in FIG. 7, the recesses 60a, 60b are arranged asymmetrically with respect to the axial center M of the support axle 40. Thus, the recess 60b is farther away from the axial center M than the recess 60a. FIGS. 7 and 8 show that a support axle 40 can only be fully inserted into the pivot bearings 22, 23 when the recesses 60a, 60b and the projections 61a, 61b are complementary. Otherwise, when the support axle 40 is inserted through the first and second openings 26, 27 into the first and second pivot bearings 22, 23, a region of the support axle 40 other than the recesses 60a, 60b strikes against the projections 61a, 61b and thus prevents complete insertion into the first and second pivot bearing 22, 23. The recesses 60a, 60b and the projections 61a, 61b thus implement a poka-yoke principle.
LIST OF REFERENCE SIGNS
[0054] 1 framework [0055] 2 frame [0056] 3 first side arm [0057] 4 second side arm [0058] 10 return roller [0059] 10a, 10b axial ends [0060] 12 longitudinal axis [0061] 20 first region [0062] 21 second region [0063] 22 first pivot bearing [0064] 23 second pivot bearing [0065] 24 first bearing surface [0066] 25 second bearing surface [0067] 26 first opening [0068] 27 second opening [0069] 28 free outlet [0070] 29 passage channel [0071] 30 first pivot arm [0072] 31 second pivot arm [0073] 40 support axle [0074] 41 first sliding body [0075] 42 second sliding body [0076] 43a, 43b, 43c, 43d contact region [0077] 44 pivot axis [0078] 50 locking device [0079] 51 stop [0080] 52 counter stop [0081] 60a, 60b recess [0082] 61a, 61b projection [0083] K1 first arc [0084] K2 second arc [0085] S1 first chord [0086] S2 second chord [0087] R radius of the first and second arcs K1, K2 [0088] L running direction [0089] G connecting straight line [0090] θ center angle of the arcs K1, K2 [0091] φ center angle at which the openings 26, 27 appear [0092] a center angle of the arc of the bearing surfaces 24, 25 [0093] r radius of the arc of the first and second bearing surfaces 24, 25 [0094] P Arrow [0095] M axial center of the support axle 40
