Composite belt, use of a composite belt and belt operation of a self-propelled combine harvester

Description

[0001] The invention relates to a composite belt comprising a cover layer and two ribs connected to the cover layer in a force-transmitting manner, each rib having the shape of a symmetrical trapezoid in cross section, each of which adjoins with its base a longer side of a rectangle, which in turn forms a cross section of the cover layer, and each rib having an elastomer material in a superstructure facing the base and in a substructure facing away from the base, and a plurality of tensile strands running parallel to one another and in the longitudinal direction of the composite belt between the superstructure and the substructure.

[0002] Furthermore, the invention relates to the use of such a composite belt in a belt drive of a self-propelled combine harvester, in particular in a belt drive driving an insertion drum or a pre-acceleration drum.

[0003] Finally, the invention relates to a belt drive of a self-propelled combine harvester, in particular a belt drive driving an insertion drum or a pre-acceleration drum.

[0004] The composite belts described above, also referred to as "composite V-belts" or "power belts," represent a combination of multiple (narrow) V-belts, with the individual V-belts arranged parallel to one another and connected to one another by the cover layer, also known as the belt backing. The advantage of composite V-belts over a corresponding number of individual belts is that they prevent twisting due to the lateral coupling, thus ensuring a completely even distribution of force across all individual ribs (corresponding to the individual belts). This results in low susceptibility to vibrations and shocks, as well as high breaking loads and resilience, and a long service life. Such composite belts are particularly suitable for large pulley center distances, which also makes them ideal for use in large agricultural machinery, such as self-propelled combine harvesters.

[0005] DE 10 2013 103 450 A1 discloses a drive system for a self-propelled combine harvester designed as a belt drive, with composite belts with two ribs also being used in certain belt drives. Typically, the various rotationally driven devices, in particular the threshing and separating devices as well as a straw chopping device, are connected via various belt drives to an output of an internal combustion engine, usually a diesel engine. In the case of DE 10 2013 103 450, a first main belt drive is proposed, which includes the main drive pulley, a first intermediate gear stage, and a second intermediate gear stage.To ensure reliable drive of the residual grain separation device, the straw chopper, and high-performance harvesting attachments, it is proposed that the first reduction gear stage directly drive the residual grain separation device via a first belt drive and the straw chopper via a second belt drive. Furthermore, the second reduction gear stage should be connected to the drives of a harvesting attachment and a cleaning device. Improvements are needed in the known combine harvester and the belt drive system implemented therein with regard to the belt drives for driving the loading drum and the pre-acceleration drum, as well as with regard to the quality of the composite belts used for the aforementioned belt drives.Further composite belts are known from the publications XP055562193 - "BELT DRIVE SYSTEMS, MAINTENANCE FREE, 35% REDUCED DRIVE COST, 67% REDUCED DRIVE WIDTH; 50% REDUCED DRIVE WEIGHT", XP055562231 - "GATES INDUSTRIAL POWER TRANSMISSION - A comprehensive product range" and US 3 948 113 A.

[0006] The invention is based on the object of proposing a composite belt for use in a belt drive of a drive system of a self-propelled combine harvester, which is characterized by high transmittable power and low manufacturing costs. Furthermore, a belt drive for driving an infeed drum or a pre-acceleration drum of a self-propelled combine harvester is to be provided, which is characterized by high power density in a limited installation space and increased efficiency through high belt utilization.

[0007] Starting with a composite belt having the features of the preamble of claim 1, the problem is solved in conjunction with the characterizing features of this claim. Accordingly, the length of the composite belt is between 2,500 mm and 2,900 mm, the breaking load of the composite belt is 45,000 N, and the power that can be transmitted by the composite belt in continuous operation is at least 50 kW.

[0008] Such a belt uses a well-known and tried-and-tested principle of double-ribbed composite belts and therefore poses no particular problems in terms of manufacturability and production costs. Nevertheless, with its special length, the aforementioned belt breaking load, which corresponds to the breaking load of a single rib (corresponding to a single belt) of 22,500 N, and the power it can transmit in continuous operation, it has a combination of features that allows for the realization of particularly space-saving and efficient belt drives for the feed drum or pre-acceleration drum drive of a self-propelled combine harvester. The selected length enables a particularly advantageous arrangement of the axes of the individual pulleys or tensioning rollers of the respective belt drives, as well as particularly large wrap angles, which enables the belt forces and torques to be transmitted safely and without slippage.The resulting torques are particularly high. Consequently, a belt drive equipped with the composite belt according to the invention achieves a particularly high power density. Nevertheless, the composite belt according to the invention deliberately does not deviate excessively from known composite belts in order to be able to largely continue to use existing manufacturing methods and the materials used for the individual components of the composite belt. Thus, with the composite belt according to the invention, there is no need to consistently use absolute "high-performance materials" or to resort to manufacturing processes with highly complex processes or particularly complex steps.

[0009] Preferably, the maximum elongation of the composite belt after operation with a minimum continuous power transmitted by the composite belt of 50 kW over a period of 200 hours is 1% of the original length of the composite belt

[0010] A length of the composite belt according to the invention between 2,600 mm and 2,800 mm is particularly advantageous. A length of 2,640 mm and a length of 2,800 mm are particularly advantageous.

[0011] In order to transmit high belt forces with a comparatively small belt cross-sectional area, at least some of the tensile strands can contain filaments that consist at least partially of an aromatic polyamide, in particular high-strength aramid, and / or carbon. Such filaments possess particularly high tensile strength and, at the same time, high flexibility, enabling even small curvature radii when operating the composite belt according to the invention in a belt drive.

[0012] The present invention also relates to a belt drive for a self-propelled combine harvester, in particular a belt drive driving an insertion drum or a pre-acceleration drum.

[0013] With respect to a loading drum drive, the belt drive according to the invention comprises two pulleys of identical diameter and preferably in the form of identical pulleys, one of these identical pulleys driving the loading drum, and a tensioning pulley arranged entirely within an envelope of the belt drive—when viewed without the tensioning pulley. According to the invention, such a belt drive comprises a composite belt as explained above.

[0014] Such a belt drive is characterized by its exceptional compactness and thus its high power density. Since the tension pulley does not extend beyond the envelope of the belt drive—when viewed without the tension pulley—valuable installation space is saved compared to conventional belt drives. In addition, the composite belt according to the invention creates a highly efficient traction device based on known technology, which can also be manufactured cost-effectively and, due to its design, is characterized by high operational reliability.

[0015] Particularly high belt forces can be transmitted, i.e. large torques or powers can be transmitted by means of the belt drive, if a respective wrap angle on the pulleys is greater than 220° and / or a wrap angle on the tension pulley is greater than 60°, preferably greater than 80°.

[0016] If the belt drive is for a pre-acceleration drum drive, the belt drive according to the invention comprises a double pulley serving as the drive, which is coupled to a threshing drum shaft, with the composite belt acting on a smaller-diameter pulley of the double pulley. Furthermore, the belt drive comprises a pulley serving as the output, by means of which the pre-acceleration drum itself can be driven, and a tension pulley arranged in a slack side, which is arranged entirely within an envelope of the belt drive—when viewed without the tension pulley.

[0017] This again results in a belt drive with outstanding power density and compactness. The composite belt according to the invention, which is also used for this belt drive, represents a tailor-made traction device that offers an excellent compromise between performance and durability on the one hand, and low manufacturing costs and the use of fundamentally known technology in the manufacturing process on the other.

[0018] The aforementioned belt drive in the form of a pre-acceleration drum drive is particularly advantageous if a wrap angle on the pulley of the double pulley having the smaller diameter is greater than 220° and / or a wrap angle on the pulley driving the pre-acceleration drum is greater than or equal to 200° and / or a wrap angle on the tensioning pulley is greater than 60°.

[0019] In this context, excellent compactness of the belt drive can be achieved if the distance of the axis of the tensioning pulley from a connecting line between the axis of the double pulley and the axis of the pulley for driving the pre-acceleration drum is less than 200 mm, preferably less than 190 mm.

[0020] The invention is explained in more detail below using several exemplary embodiments of both a composite belt and two belt drives. It shows: Fig. 1: A cross-section through a composite belt, Fig. 2: A side view in the direction of travel on the left of a combine harvester showing a loading drum drive, Fig. 3: The loading drum drive according to Figure 2 , Fig. 4: a side view in the direction of travel to the right of the combine harvester according to Figure 2 with representation of a pre-acceleration drum drive and a threshing drum drive and Fig. 5: the pre-acceleration drum drive according to Figure 4.

[0021] One in Figure 1 The composite belt 1 (composite V-belt) shown in cross-section consists of a cover layer 2 with a flat, rectangular cross-section and a thickness 3 and a width 4. The thickness 3 is 13 ± 2 mm and the width 4 is 37 ± 2 mm. A surface 5 of the cover layer 2 forms a so-called back of the composite belt 1. A longitudinal direction of the composite belt runs perpendicular to the plane of the drawing.

[0022] The cover layer 4 forms a composite with two parallel ribs 6, each trapezoidal in cross-section, which extend from a surface 7 opposite the surface 5. Between the ribs 6 there is a groove R, which is also trapezoidal in shape. The trapezoids forming the cross-section of the ribs 6 each have a base 8 and a base side 9 running parallel thereto, opposite the base 8, which each delimits a surface of the composite belt 1 opposite the surface 5. The respective legs 10 of the two trapezoids 8 each enclose an angle 12 of 39 ± 3° with a straight line 11 running perpendicular to the surface 7.

[0023] The cover layer 2 consists of an elastomer material in the form of fabric-reinforced chloroprene.

[0024] The cross-section of the ribs 6 can be divided into a superstructure 13 facing the cover layer 2 and a substructure 14 extending from the base side 9 to the superstructure 13. The sum of the height of the superstructure 13 and the height of the substructure 14 thus corresponds to the total height 15 of the rib 6.

[0025] Between the superstructure 13 and the substructure 14, i.e., approximately half enclosed by each, there are tension cords 16 in each rib. These are arranged parallel to each other and run within a plane aligned parallel to the surface 5 forming the back. In the present case, there are at least 6 tension cords 16 per rib 6. Each tension cord 16 consists of a multifilament thread with a diameter of 1.9 mm to 2 mm. The individual filaments that form the respective tension cord 16 are made of aromatic polyamide.

[0026] The superstructure 13 and the substructure 14 of each rib 6 each consist of an elastomer material in the form of fiber-reinforced chloroprene.

[0027] In addition, each rib 6 is provided on its outer sides with two sheaths 17, 18 made of a fabric. The outer sheath 17 forms, in cross-section, both the base 9 and the base 8, as well as the two legs 10 ("flanks" of the composite belt 1) of the trapezoid. The inner sheath 18 is located at a very short distance within the outer sheath 17.

[0028] The (stretched) length of the composite belt 1 forming a closed ring is in particular 2,640 mm (for an insert drum drive) or 2,800 mm (for a pre-acceleration drum drive).

[0029] One in Figure 2The schematically illustrated self-propelled combine harvester 20 basically has a structure known from the prior art, but has a special design according to the invention, particularly with regard to the belt drives for driving a loading drum and a pre-acceleration drum. Figure 2 The position of a belt drive 22 arranged on the left side in the direction of travel 21 for driving an insertion drum is illustrated. Further details of the structure of the belt drive 22 can be found in Figure 3 :

[0030] The belt drive 22 has two pulleys 23, 24, each of which is identical in design and, in particular, has an identical diameter. In this context, the diameter of a pulley is understood to be the distance of the neutral axis of the (composite) belt running on a pulley, measured diametrically through the axis of the respective pulley.

[0031] The axis 25 of the pulley 23 corresponds to the axis of a threshing drum or threshing drum shaft, to which the pulley 23 is torque-locked. The direction of rotation of the pulley 23 is indicated by arrow 26. The pulley 24 drives a harvesting drum of the combine harvester in a manner not shown in detail but known in the art.

[0032] In a slack strand 27 of the composite belt 1 there is a tensioning roller 28 which is pressed against the back of the composite belt 1 by means of a tensioning device not shown in detail but known in order to maintain a certain belt tension.

[0033] If the belt drive 22 is considered without the tension pulley 28, an envelope curve H around the belt drive 22 is formed, on the one hand, by a load strand opposite the slack strand 27 and, on the other hand, by a straight section 30 running tangentially to the two pulleys 23 and 24. In addition, the semicircular sections of the composite belt 1 enclosing the pulleys 23 and 24 form parts of the envelope curve. It is the Figure 3 It can be clearly seen that the tensioning pulley 28 is completely within the envelope curve of the belt drive 22 as defined above.

[0034] In this case, the diameter of the two pulleys 23 and 24 is 350 mm each, and the diameter of the tension pulley is 163 mm. The wrap angle at pulley 23 is 228°, at pulley 24 it is 222°, and at the tension pulley it is 90°.

[0035] The distance between the axis 25 of pulley 23 and the axis 31 of pulley 24 is 685 mm. The distance between the axis 25 of pulley 23 and the axis 32 of tension pulley 28 is 325 mm. The distance between the axis 32 of tension pulley 28 and the axis 31 of tension pulley 28 is 326 mm. As previously stated, the length of the composite belt is 2,640 mm.

[0036] Furthermore, a distance A of the axis 32 of the tension pulley 28 from a connecting straight line V between the axis 25, the pulley 23 and the axis 31 of the pulley 24 is 25 mm.

[0037] In an analogous manner to Figure 2 shows Figure 4 a side view of the combine harvester 20, in this case the right side (viewed in the direction of travel 21). Figure 4 The position of a belt drive 33, which serves to drive a pre-acceleration drum, can be seen schematically. Figure 4A threshing drum drive is also shown schematically, which is formed by a second belt drive 34, the structure and function of which are not relevant in this case. Figure 5 The details of the belt drive 33 for driving the pre-acceleration drum can be seen:

[0038] The belt drive 33 comprises a double pulley 35, which comprises a pulley 36 with a smaller diameter and a pulley 37 with a larger diameter and is designed as a one-piece composite component so that the two pulleys 36, 37 are inseparable from one another. The two pulleys 36, 37, i.e. the double pulley 35, have a common hub 38 which accommodates a threshing drum shaft 39 which is rotatable about the axis 40. The composite belt 1 also runs around a pulley 41 with an axis 42, wherein the pulley 41 serves to drive a pre-acceleration drum. The pre-acceleration drum pre-accelerates the crop delivered at the end of the inclined conveyor to approximately 80% of the peripheral speed of the threshing drum. The crop is then transferred from the pre-acceleration drum to the threshing drum.

[0039] In addition, the composite belt 1 runs in the belt drive 33 with its back-forming surface 5 around a tensioning roller 43 which, like the tensioning roller 28 in the belt drive 22 already mentioned above, is provided with a tensioning device not described in detail or known.

[0040] The running direction of the composite belt 1 or the direction of rotation of the pulley 41 or double pulley 35 is illustrated by the arrow 44.

[0041] In the belt drive 33, the wrap angle at the pulley 36 of the double pulley 35 is 229°, the wrap angle at the pulley 41 is 200°, and the wrap angle at the tension pulley 43 is 69°. The distance between the axis 40 of the double pulley 35 and the axis 42 of the pulley 41 is 610 mm. The distance between the axis 45 of the tension pulley 43 and the axis 42 of the pulley 41 is 335 mm, and the distance between the axis 45 of the tension pulley 43 and the axis 40 of the double pulley 38 is 378.5 mm. The length of the composite belt 1 of the belt drive 33 is 2800 mm.

[0042] The distance of the axis 45 of the tension pulley 43 to a connecting line V between the axis 42 of the pulley 41 and the axis 40 of the double pulley 35 is 190 mm.

[0043] As in the embodiment according to the Figures 2 and 3the tension pulley 43 lies completely within an envelope H, which envelops the belt drive 33. In this case, the envelope H runs around the pulley 37 with the larger diameter, as can be seen from Figure 5 results. List of reference symbols

[0044] 1Composite belt 2Cover layer 3Thickness 4Width 5Surface 6Rib 7Surface 8Base 9Base side 10Leg 11Straight 12Angle 13Superstructure 14Substructure 15Total height 16Tension cord 17Covering 18Covering 20Combine harvester 21Direction of travel 22Belt drive 23Pulley 24Pulley 25Axle 26Arrow 27Slack side 28Idler pulley 30Straight section 31Axle 32Axle 33Belt drive 34Belt drive 35Double pulley 36Pulley 37Pulley 38Hub 39Threshing drum shaft 40Axle 41Pulley 42Axle 43Idler pulley 44Arrow 45Axle 46Empty strand ADistance HHenvelope RRrille VConnecting line

Claims

1. A composite belt (1) comprising a cover layer (2) and two ribs (6) connected thereto in a force-transmitting manner, wherein in cross section, each rib (6) has the shape of a symmetrical trapezoid and respectively connects via a base (8) to a longer side of a rectangle which a cross section of the cover layer (2) forms, and wherein, in an upper structure (13) facing the base (8) and in a lower structure (14) facing away from the base (8), each rib (6) has a respective elastomeric material as well as a plurality of tension cords (16) between the upper structure (13) and the lower structure (14) which are respectively parallel to each other and respectively extend in the longitudinal direction of the composite belt (1) in order to take up the longitudinal forces to be transmitted by the composite belt (1), characterized in that the length of the composite belt (1) is between 2500 mm and 2900 mm, the breaking load of the composite belt (1) is 45000 N and the power which can be transmitted by the composite belt (1) in continuous operation is at least 50 kW.

2. The composite belt according to claim 1, characterized in that a maximum elongation of the composite belt (1) after an operation with a minimum continuous power of 50 kW transmitted by the composite belt (1) over a time period of 200 hours is 1% of the original length of the composite belt (1).

3. The composite belt according to claim 1 or claim 2, characterized in that the length is between 2600 mm and 2800 mm, in particular 2640 mm or 2800 mm.

4. The composite belt according to one of claims 1 to 3, characterized in that at least a portion of the tension cords (16) contains filaments which consist at least in part of an aromatic polyamide, in particular high strength aramid, and / or carbon.

5. Use of a composite belt (1) according to one of claims 1 to 4 in a belt drive (22, 33) of a self-propelled combine harvester (20), in particular in a belt drive (22, 33) driving a feed drum or a pre-acceleration drum.

6. The use according to claim 5, characterized in that the belt drive (22) has two belt pulleys (23, 24) with identical diameters, with the feed drum being capable of being driven by means of one belt pulley (24), wherein a tensioning roller (28) is disposed in a slack side (27) of the belt drive (22) and is disposed entirely within an envelope (H) of the belt drive (22) - considered without the tensioning roller (28).

7. The use according to claim 6, characterized in that a respective wrap angle at the belt pulley (23, 24) is greater than 220° and / or a wrap angle at the tensioning roller (28) is greater than 60°, preferably greater than 80°.

8. The use according to claim 5, characterized in that the belt drive (33) has a double belt pulley (35) serving as the drive, and which is coupled to a threshing drum shaft (39), wherein the composite belt acts on a belt pulley (36) of the double belt pulley (35) which has a smaller diameter, and furthermore has a belt pulley (41) acting as the output, by means of which a pre-acceleration drum can be driven, and has a tensioning roller (43) disposed in a slack side (46) and which is disposed entirely within an envelope (H) of the belt drive (33) - considered without the tensioning roller (43), wherein the envelope (H) wraps round the belt pulley (37) of the double belt pulley (35) with the larger diameter.

9. The use according to claim 8, characterized in that a wrap angle at the belt pulley (36) of the double belt pulley (35) with the smaller diameter is greater than 200° and / or a wrap angle at the belt pulley (41) driving the pre-acceleration drum (41) is greater than or equal to 200° and / or a wrap angle at the tensioning roller (43) is greater than 60°.

10. The use according to claim 9, characterized in that a distance of the axis (45) of the tensioning roller (43) from a straight connecting line (V) between the axis (40) of the double belt pulley (35) and the axis (42) of the belt pulley (41) for driving the pre-acceleration drum is less than 200 mm, preferably less than or equal to 190 mm.

11. A belt drive for a self-propelled combine harvester (20), in particular a belt drive (22, 23) driving a feed drum or a pre-acceleration drum, characterized by a composite belt (1) in accordance with one of claims 1 to 4.