DE8313127U1 - Rotary mower - Google Patents

Description

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Claims (7)

The invention relates to a rotary mower as defined in the preamble of claim 1. The rotary mowers with top drive that have become widespread in recent years, usually referred to as drum mowers, have skids as support to the ground. These plate-like support elements are preferably freely rotatable and are mounted on the drum drive shaft via ball bearings. This skid is attached at a fixed distance from the drum, so that a gap is formed between the drum edge and the skid edge through which the knife blade can pass. This fixed distance also determines the cutting height of the mower. In practice, it is sometimes necessary to increase this cutting height, for example when the ground is not level enough for field crops and there is a risk of the feed becoming contaminated. As a primitive solution, one or more shims are screwed between the skid and the fastening element to the drum axle, or the normal skid is replaced with a higher one. This change in cutting height is simple, but very time-consuming and not acceptable for short-term changes in cutting height. In order to eliminate this disadvantage, various solutions have been proposed. For example, in DE-PS 19 15 472, the height of the mowing rotor is changed instead of the skid. This design appears to be advantageous, but it has a significant disadvantage. If, for example, swath guide plates are used to limit the swath width, these must be brought very close to the mowing drum in order to work properly. When the cutting height is adjusted via the drum, it is therefore necessary with this known design that the swath plate is also adjusted. In various other proposed solutions for changing the cutting height, for example in DE-OS 15 82 311 and in AT-PS 261 962, a height adjustment of the skid is described, which is very complicated to carry out because the Adjustment of the skid can be carried out directly and only with excessive manual work. A skid adjustment built for practical use is generally based on the fact that a hollow shaft is provided for the rotary drive and an axle is then guided through this hollow shaft, to which the skid is attached. This axle is guided through the upper gearbox of the mower and enables a relatively inexpensive and simple adjustment. However, such designs are not cheap because the hollow shaft !requires significantly larger drive wheels and, in addition, mowers with more than two drums require complicated drive systems due to the corresponding, sometimes opposing, rotation directions of the drums. The invention is therefore based on the object of achieving an adjustment possibility for the runner, in which neither the expensive implementation of the runner axis through the drive of the drum is necessary, nor a complicated adjustment on the runner has to be carried out directly. This object is achieved by the features or structural means proposed in the characterizing part of claim 1, whereby the runner adjustment can be carried out from above, as is known per se, using an appropriate key or the like. Details of the invention, advantages and specific features are apparent from the following description of preferred embodiments and the drawings. They mainly show in cross-sectional images: Fig.l an adjustment device in which the runner is adjusted via a thread and secured by a locking screw, Fig.2 a vertical displacement of the runner, which is moved axially against a mounting bush by means of an adjusting screw, Fig.3 an embodiment in which an axis the skid is inserted into a hollow shaft of the drive shaft of the gyro and is adjustable in height using an adjusting screw, Fig.4 is a modified version of the illustration in Fig.3, in which the adjustment device with the adjustment screw is guided upwards and finally Fig.5 shows an adjustment option for an inner runner, which can also be adjusted from above compared to the outer runner. Fig.6 an adjustment option similar to Fig. 2. According to Fig.l, on the drive shaft 1 of the drum la a i
Threaded bushing 2 is rotatably mounted, onto which an outer hub 3 with an internal thread is screwed. This hub 3 has one or more grooves 3a running parallel to the drive shaft 1 and is welded to the runner 4 and a pot 5. To fix the desired cutting height, the locking screw is screwed into the groove 3a of the hub 3. The screw 6 is guided in a threaded piece 7, which is welded to a pot 5. If the height is to be adjusted, a key 8 is first passed through the opening 9 in the ring collar 9a of the gyro and placed on the locking screw 6. This is then unscrewed until it releases the groove 3a in the hub 3. By turning the runner 4, this can be adjusted up or down in the internal thread of the hub 3. After the adjustment process, the working position of the drum la is held using the locking screw 6. Fig. 2 shows a design in which an inner hub 10 is also mounted on the drive shaft 1, over which an outer hub 11, which is welded to the runner 4, is pushed. Using the adjusting screw 12, these two hubs 10, 11 can be moved against each other and the runner 4, so that the cutting height can be adjusted to different levels. For better and more stable guidance of the runner 4, Fig. 3 shows an embodiment in which the rotor drive shaft is designed as a partial hollow axle 13 and into which the runner axle 14 is inserted. A bushing 15 is mounted on this runner axle 14 and is welded to the runner 4. A threaded piece 17 is also welded to the runner axle 14, which projects horizontally outwards through an opening 16 in the partial hollow shaft 13. An adjusting screw 18 can engage in this threaded piece 17, the counter bearing of which is located in the eye 20. By inserting a key 8 through an opening 19 in the bearing tube 19a, the runner 4 can then be moved axially and the cutting height can thus be adjusted in this way. Fig. 4 shows an improved version according to Fig. 3. The gyro axle is also designed as a partial hollow shaft 13, into which the skid axle 14 is inserted coaxially. The bushing 15, which is welded to the skid 4, is mounted on this. A cylindrical pin is guided through the skid axle 14, which extends outwards through slots 21 in the partial hollow shaft 13 and is simultaneously guided in the slots 21. An inner sliding sleeve 28 is pushed over the partial hollow shaft 13, in which the cylindrical pin 22 is supported at both ends. An outer sliding sleeve 23 is connected via ball bearings 23a to the inner sliding sleeve 28, on which a threaded piece 24 is arranged, which is guided outwards through a slot 25 in the bearing sleeve 29. An adjusting screw 26 is guided in this threaded piece 24, which is designed as a crank 27 at its upper end. This design ensures that the adjusting screw 26 can be operated without inserting a key, which makes the adjustability significantly simpler and easier. Finally, Fig. 5 shows a special embodiment of the cutting height adjustment. While in the previously shown embodiments the gap A between the drum disc and the edge of the skid 35, through which the blade 39 emerges, is widened by increasing the cutting height, so that dirt or stones can enter the interior between the drum disc 40 and the skid 35, in the embodiment according to Fig. 5 this gap remains unchanged in every position of adjustment due to the special design of the skid as an inner and outer skid, and the interior is thus protected. A hub 31 is mounted on the drum shaft 30, to which a pot 32 is welded, to which the skid 35 is in turn attached. A bushing 33, to which the inner skid 34 is welded, is pushed over the hub 31. With the help of the adjusting screw 36 and a key 38, which can be inserted through a hole 37, the bushing and hub 31 are moved against each other and the cutting height is adjusted by adjusting the inner skid 34. A further embodiment is shown in Fig. 6. For better accessibility, the adjusting screw 12 is rotatably mounted in the flange of the knife drum and the hub 41 is screwed into the protruding flange part. When the adjusting screw 12 is turned, the hub 41 and with it the runner 4 move on the drive shaft 1, so that the runner can be adjusted axially. t < Summary. In a rotary mower equipped with mowing drums and support skids, the distance between the support skid (4) and the ring collar (9a, 40) should be able to be changed quickly and easily if necessary, which is essentially achieved by providing an inner hub (10) and an outer hub (11) welded to the skid (4) at the lower end of the drive shaft (1). Both hubs (10, 11) have protruding flange parts with aligned holes. One of these holes is provided with an internal thread for receiving an adjusting screw (12), by means of which the outer hub (11) can be vertically adjusted together with the skid (4) using a tool, e.g. a socket wrench (8) or the like. (Fig. 2). - 10 - (»if * f. -'10'- Reference symbol list 1 Drive shaft (Fig.l) 21 slots la drum 22 Cylinder pin 2 Threaded bushing 23 outer sliding sleeve 3 Outer hub with internal thread 23a ball bearing 3a Groove 24 Threaded piece 4 Skid 25 Slot 5 Pot 26 Adjusting screw 6 Locking screw 27 Crank 7 Threaded piece 28 inner sliding sleeve 8th Key 29 Bearing sleeve 9 Opening \ 30 Drum shaft 9a Ring collar 31 Hub 10 Hub (inner) 32 Pot 11 Hub (outer) 33 socket 12 Adjustment screw 34 Inner runner 13 Partial hollow axle 35 Skid wall skid 14 Skid axle 36 Adjusting screw 15 Rifle 37 Bore 16 breakthrough 38 keys 17 Threaded piece 39 knives 18 Adjusting screw 40 ring collars. 19 breakthrough 41 Hub 19a Bearing tube 42 Flange 20 Eye (as counter bearing) c &diams; · Expectations. 1. Device for changing or adjusting the cutting height of a tractor-drawn rotary mower, in particular one equipped with rotating drums equipped with cutting blades, in which there is an axially height-adjustable skid below the blade drum, by means of a tool that can be operated from the outside and can engage with an adjusting screw or the like, e.g. a key or the like. characterized , that the adjustment device is actuated from above, off-centre through the drum cylinder (Fig.4, Pos.la) or through the drum edge (9a). 2. Device according to claim 1, characterized in that an inner hub (10) is mounted on the lower end of the drive shaft (1), over which an outer hub (11) is pushed, which is welded to the runner (4), whereby the two hubs (10, 11) have laterally protruding flange parts with aligned holes, the lower of which is provided with an internal thread for receiving the adjusting screw (12), by means of which the outer hub (11) can be adjusted vertically together with the runner (4) using a tool, e.g. a socket wrench (8) or the like. (Fig.2) 3. Device according to claim 1, characterized in that the gyro axis forms a partial hollow shaft (13) into which the skid axis (14) is coaxially inserted, which is penetrated in the upper region by a horizontal cylindrical pin (22), the free ends of which protrude through slots (21) in the partial hollow shaft (13) to accommodate an inner sliding sleeve (28), into which the inner sliding sleeve (28) is also pushed, which is connected via ball bearings (23a) to an outer sliding sleeve (23), on which a threaded piece (24) is arranged, which leads outwards through a slot (25) cut out in a bearing sleeve (29) and on which the threaded part of an adjusting screw (26) engages (Fig. 4) 4. Device according to claim 1, characterized in that the skid axis (14) is axially displaceable in the drum drive shaft designed as a partial hollow shaft (13) via a threaded piece (17) and an adjusting screw (20). (Fig.3) 5. Device according to claim 1, characterized in that a threaded hub (2) is rotatably mounted on the drum shaft (1), onto which a threaded bushing (3) of the runner (4) is screwed and can be actuated by means of a locking screw (6) \by a key (8) passed through the opening (9) of the ring collar (9a) &bull;, the screw (6) being guided in a threaded piece (7) and the free end of the locking screw (6) penetrating into a longitudinal groove (3a) to lock the runner (4) (Fig.l). 6. Device according to claim 1, characterized in that the inner runner (34) consists of an outer and an inner runner part, the inner runner (34) being axially displaceable on a rotatable hub (31) of the drum shaft (30) and being adjustable by means of an adjusting screw (36) in conjunction with a wrench (38) which is guided through a bore or through an opening (37) (Fig. 5). 7. Device according to claim 1, characterized in that at the lower end of the drive shaft (1) there is a movable hub (41) which has a protruding flange part into which an adjusting screw (12) is screwed, which is rotatably mounted in the flange (42) of the knife drum, so that when the adjusting screw (12) is turned the skid (4) moves axially (Fig.6),