GB1600094A

GB1600094A - Hay-making machines

Info

Publication number: GB1600094A
Application number: GB1961878A
Authority: GB
Original assignee: C Van der Lely NV
Current assignee: C Van der Lely NV
Priority date: 1977-05-18
Filing date: 1978-05-15
Publication date: 1981-10-14
Also published as: FR2390895A1; DE2820535A1; NL7705479A

Description

(54) IMPROVEMENTS IN OR RELATING TO HAY-MAKING MACHINES (71) We, C. VAN DER LELY N.V., of 10, Weverskade, Maasland, The Netherlands, a Dutch Limited Liability Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to hay-making machines.

According to the present invention there is provided a hay-making machine comprising at least one rake member drivable about an upwardly extending axis of rotation, the rake member having a central part and a plurality of tines, the tines at least in operation being movable with respect to said central part in a direction of height by means of a quadrangular hinge structure by which the tines are connected to said central part.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a plan view of a hay-making machine shown attached to a tractor and disposed in a working position, Figure 2 is a side view of the machine as illustrated in Figure 1, Figure 3 is a plan view similar to Figure 1 but showing the machine in a transport position, Figure 4 is a view, partly in section, taken on line IV-IV in Figure 1, Figure 5 is a view in the direction of arrow V in Figure 4, Figure 6 is a view also taken in the direction of the arrow V in Figure 4, but of an alternative embodiment, Figure 7 is a view of the embodiment of Figure 6 taken in the direction of arrow VII in Figure 6, Figure 8 is a view, partly in section, of the construction of a tine connection used in rake members of the machine of Figure 1, Figure 9 is a view in the direction of arrow IX in Figure 8, and Figure 10 is a view in the direction of arrow IX in Figure 8 but of an alternative embodiment.

The hay-making machine shown in Figures 1 to 5 has a front (with respect to the intended operative travelling direction C of the machine) frame portion 1 and a rear frame portion 2 which are connected to one another in freely pivotable manner with the aid of a hinge construction 3.

The rear frame portion 2 is provided with two rake members 4 and 5, which are drivable in opposite directions A and B about rotary shafts 6 and 7 respectively.

These shafts 6 and 7 are parallel to one another and are inclined upwards to the front, viewed with respect to the direction of travel C, at an angle of about 5 to 20 to a vertical plane at right angles to the direction of travel C. The front frame portion 1 is attached in a manner to be described hereinafter to the tractor 8 for propelling the machine, there being beneath the front part of each rake member 4, 5 a ground wheel 9 or 10 respectively, the axle of which is stationary with respect to the rear frame portion 2 during operation so that these ground wheels determine the orientations of the rake members 4 and 5 with respect to the tractor 8.

At the front the front frame portion 1 is provided with a trestle 11 (see particularly Figures 4 and 5) in the form of an inverted U. In known manner the top of this trestle has a top anchorage 12 in the plane of symmetry of the trestle for connection with the top arm of the lifting device of the tractor 8, whereas near the lower ends of the legs of the trestle 11 lower anchorages 13 and 14 are provided for fastening the machine to the lower lifting arms of the lifting device of the tractor.

One of the legs of the trestle 11 (viewed in the direction of travel C, the left-hand leg in this embodiment) has secured to it a tubular carrier 15 forming part of the front frame portion 1 and extending from the trestle 11 to the rear with respect to the direction of travel C and substantially parallel to the direction C. During operation the carrier 15 is substantially horizontal and is fastened to a zone of the lefthand leg of the trestle 11 located substantially midway up the height of the trestle. Near its rear end the carrier 15 has rigidly secured to it a supporting tube 16 of the front frame portion 1 which extends from where it is fastened to the carrier 15 to the front and in upward direction, its front end being fastened to the horizontal part of the trestle 11 near the verticle plane of symmetry of the trestle. Near the rear end of the carrier 15 is furthermore rigidly secured a Usection beam 17 of the front frame portion 1, which extends during operation from this rear end in a substantially horizontal direction inclined to the front, the front end of this beam 17 being fastened to the vertical leg of the trestle 11 remote from the leg with the carrier 15 (that is to the right-hand leg in the illustrated embodiment). On the lower side the beam 17 is provided with a support 18 also forming part of the front frame portion 1 and which is near the rear end of the beam 17 and near the area where the beam is fastened to the carrier 15. The support 18 has at the lower end a bearing 19 holding a shaft 20 which projects both to the front and the rear of the bearing 19. The shaft 20 has at both ends axial key ways.

The centre line of the shaft 20 is horizontal and parallel to the direction of travel C.

The rear end of the carrier 15 is provided with a fork-like member 21 holding a pivot shaft 22, which forms part of the hinge construction 3. The centre line of the pivot shaft 22 is substantially vertical during operation. As best seen in Figure 4, the pivot shaft 22 is located on one side of the trestle 11 near the vertical leg of the trestle 11 to which the carrier 25 is fastened.

The pivot shaft 22 also has a fork-like member 23 which is associated with the rear frame portion 2. The topmost part of the fork-like member 23 extends during operation and as viewed with respect to the direction of travel C, laterally in a horizontal direction from the pivot shaft 22 in the direction away from the vertical leg of the trestle carrying the carrier 15 towards the vertical leg of the trestle 11 to which is fastened the front end of the beam 17, that is the member 23 extends from left to right in Figures 4 and 5 and forms an extension arm 24. Viewed in plan (Figure 1), this extension arm 24 extends at right angles to the direction of travel C in the operational position. The end of the extension arm 24 remote from the shaft 22 has a hole 25, the axis of which is vertical.

The fork-like member 23 is rigidly secured to the front end of a carrier 26 which forms a part of the rear frame portion 2 and which extends from this forklike member substantially horizontally to the rear in the operational position shown in Figure 1, parallel to the direction of travel C. The rear end of the carrier 26 is fast with a clamping piece 27 (Figure 1) of the rear frame portion 2 that is adjustably secured to the front of a frame beam 28 which is, in the operational position of Figure 1, substantially horizontal and at right angles to the direction of travel C. At the front of the clamping piece 27 a second carrier 29 of the rear frame portion 2 is provided having its rear end fast with the clamping piece 27 spaced apart from the rear end of the carrier 26. The front end of the carrier 29 is welded to the carrier 26 near the fork-like member 23. In the embodiment shown the centre line of the substantially horizontal carrier 26 is located in the vertical plane midway between the rotary shafts 6 and 7. The vertical plane that lies in the direction of travel C and that contains the axis of the pivot shaft 22 is located near the left-hand (Figures 4 and 5) vertical leg of the trestle 11 and is at a distance from the vertical plane of symmetry of the trestle 11 and from the coinciding plane of the tractor 8.

Fastening by means of the clamping piece 27 permits the frame beam 28 to be fixed in place, in its direction of length, at different areas with respect to the rear of the carrier 26. To each end of the frame beam 28 is fastened a gear box 30 or 31 respectively, in which are journalled the hubs of the rake members 4 and 5 that rotate about the rotary shafts 6 and 7 respectively. The gear box 31 has an input shaft 32, the axis of which is at an angle other than 90" to a plane containing the axes of the rotary shafts 6 and 7. In the embodiment shown in Figure 1 this angle is about 45". The axis of the shaft 32 is directed from its point of intersection with the axis of the rotary shaft 7 forwardly in an inclined position towards the rake member 4 and towards the hinge construction 3. The axes of the frame beam 28, the shaft 22 and of the carrier 26 are located in a common plane which is substantially horizontal during operation. The gear box 30 of the rake member 4 is driven in known manner from the gear box 31 by means of a transmission shaft located in the frame beam 28.

Figures 6 and 7 show a variant of the hinge construction 3, in which parts corresponding to parts already described are designated by the same reference numerals as used in Figures 4 and 5. In the con struction shown in Figures 4 and 5 the machine can be locked in a transport position (Figure 3) by means of locking members, that is to say by inserting a locking pin 33 into the hole 25 of the extension arm 24 that is fast with the rear frame portion 2, and into a hole in the beam 17 above the support 18 of the first frame portion 1. Locking in this same transport position in the embodiment shown in Figures 6 and 7 is achieved by means of a locking hook 34 which, in the locking position, snaps around a cam 35 welded to the extension arm 24 at a distance from the pivot shaft 22, the components 34 and 35 forming in this case the locking means. The locking hook 34 is pivotable about a pivot shaft 36 secured to the supporting tube 16 of the front frame portion 1, the centre line of the pivot shaft 36 being substantially horizontal and, as shown in Figure 6, parallel to the supporting tube 16. The pivot shaft 36 is surrounded by a torsion spring 37 which acts to turn downwards the end of the hook 34 remote from the pivot shaft 36. At the end remote from the pivot shaft 36 the hook 34 is provided, on its lower side, with a slanting part 34A which comes into contact with the cam 35 during change-over to the transport position. To the end of the hook 34 remote from the pivot shaft 26 is fastened a cable 38 which is inclined upwardly and is passed, near the top of the nearest vertical leg of the trestle 11, around a roller or a rotatable pin 39, the end of the cable 38 remote from the hook 34 being located within reach of the tractor driver.

Figures 8 and 9 show one of the, for example, six groups of tines 42 of each of the rake members 4 and 5 and the fastening mode thereof. The paths described by the ends of the tines of the two rake members in (operation overlap one another if the rake members are driven in opposite senses. The rake members each have a plurality of spokes 40 (Figure 1), for example six, which are fastened at the top to the hub of the rake member and are directed downwards from the hub (Figure 2). To the lower ends of the spokes 40 of each rake member 4, 5, is fastened a circular rim 41, which is parallel to a plane at right angles to the rotary shaft 6 or 7 respectively. Near each group of tines 42 the rim 41 has fastened to it a flat support 43 which is parallel to a plane at right angles to the rotary shaft 6 or 7 respectively and which extends inwardly from the rim 41. Each support 43 holds a pivot shaft 44, the axis of which is parallel to the rotary shaft 6 or 7 and which is located near the rim 41. The top of each support 43 is provided with a plate 45 which is pivotable about the pivot shaft 44 with respect to the associated support 43. Viewed in plan the plate 45 has the same shape as the support 43 and can adopt the same position, as shown in Figure 9. Each plate 45 has two holes 46 and 47, whilst the support 43 has a hole that registers with the hole 47 in the position shown in Figure 9 and that can be brought, instead, into registry with the hole 46. The plate 45 can turn about the pivot shaft 44 with respect to the support 43 and can be fixed in either of two positions by means of a locking pin 48, which can be inserted into one or other of the holes 46 or 47 of the plate 45 and into the hole just mentioned in the support 43. In one position the tines of the group 42 extend substantially radially to the outside; in the other they are in a trailing position with respect to the direction of rotation A, B. The first-mentioned of the positions serves for tedding crop; the trailing position is used to form swaths in which case a swath-forming device (not shown) may be employed.

To the top of the plate 45 is welded a flat support 49 which is fastened near the edge of the plate 45 remote from the rim 41, that is to say, at a distance from the rim 41. In one of the locked positions the plane of symmetry of the flat support 49 extends substantially radially. Near the lower end located at the plate 45 and near the end remote from the plate 45 the upwardly extending support 49 is provided with pivot shafts 50 and 51 resepctively, the pivot shaft 51 being arranged at a forklike top end of the support 49. The two pivot shafts 50 and 51 are parallel to one another and extend substantially parallel to an adjacent tangent to the rim 41.

As shown in Figure 8, the plane containing the axes of the pivot shafts 50 and 51 is at an angle of about 60 to the top surface of the plate 45, this angle being open outwardly of the rake member. A pair of arms 52 and 53 located on either side of the support 49 is pivotable about each of the pivot shafts 50 and 51. Through the ends of the arms 52 and 53 remote from the pivot shafts 50 and 51 respectively are passed pivot shafts 54 and 55 respectively, khich are each parallel to the pivot shafts 50 and 51. The pivot shafts 54 and 55 are interconnected by an upwardly extending carrier 56 which extends substantially parallel to the rotary shaft 6 or 7 of the rake member concerned in operation.

Each group of tines 42 is fastened by means of a bolt 57 at an area located midway between the pivot shafts 54 and 55.

Each group of tines 42 comprises two tines 58 and 59 made from a single length of material. The tines 58 and 59 have the same shape and the same dimensions as each other and are interconnected by a number of coils on each side of the fastening bolt 57. In the normal working position (Figure 8) each tine 58, 59 extends outwardly away from the remainder of the rake member, the imaginary inward extension of the tine crossing or intersecting at right angles the rotary axis of the rake member concerned. The end portion of each of the tines is bent over downwards.

Viewed in plan (Figure 9) the end portion of each tine is in line with the inner portion of the tine.

The pivot shafts 50, 51, 54 and 55, having no common point with the rotary axis of the rake member concerned, are located at the corners of a trapezium, of which the sides formed by lines interconnecting the axes of the pivot shafts 50, 54 and 51, 55 as viewed in Figure 8 are parallel to one another and parallel to a plane at right angles to the rotary axis. It will be appreciated that, in effect, the pivot shafts 50, 51, 54 and 55 constitute the four pivot points of w quadrangular hinge structure.

In the embodiments shown in Figure 10 the pairs of arms 52 and 53 are replaced by cranks 62 and 63 respectively, whilst the relative disposition of the pivot shafts 50, 54, 55 is the same as that shown in Figures 8 and 9. This embodiment has, however, a simpler structure.

During operation and transport the machine is connected by means of the anchorages 12, 13 and 14 of the trstle 11 with the lifting device of the tractor 8. An auxiliary shaft 64 (Figures 1, 2 and 3) is coupled at its front end with the power take-off shaft of the tractor and at its rear end with the front end of the shaft 20 carried by the front frame portion 1.

A transmission shaft 65, which is a part of the machine, is coupled at one end with the rear end of the shaft 20 and at the other end with the input shaft 32. The shaft 65 has two universal joints 66 and 67 and has a telescopic structure.

During operation the rear frame portion 2 together with the rake members 4 and 5 is freely pivotable as a whole about the centre line of the pivot shaft 22, which is located, with respect to the direction of travel C, approximately midway between the front of the trestle 11 and the frame beam 28. In this way the frame beam 28 together with the rake members 4 and 5 will not exert disturbing forces on the tractor which might otherwise adversely affect the steering of the tractor. The movements of the frame beam 28 and of the rake members 4 and 5 with respect to the front frame portion 1 are limited by the steering wheels 9 and 10.

Although the Figures show only two rake members, the construction described can also be utilised in cases in which a larger number of rake members are arranged side by side on the rear frame portion 2. With machines having, for example, six rake members side by side the steering of the tractor could be considerably affected. Like-wise, if the rake members are rotated in the same direction, in which case heavy lateral forces may be produced, this free pivotability about the pivot shaft 22 is important. The movements of the rear frame portion 2 with respect to the front frame portion are not hindered by the transmission shaft 65, which has a telescopic structure. The coupling shaft 20, which is mounted in a fixed position with respect to the front frame portion 1, provides the advantage that with a freely pivotable frame beam 28 the auxiliary shaft 64 is not exposed to the risk of striking the fastening construction between the machine and the tractor. The free pivotability of the rear frame portion 2 with respect to the front frame portion 1 allows the tractor to make sharp bends without the need for lifting the machine.

In order to move the rake members 4 and 5 into a transport position, in which the width of the machine is appreciably smaller than in the working position, viewed in the direction of travel C, the tractor is driven through a sharp bend so that owing to the fixed ground wheels 9 and 10 the rake members initially continue in the original direction of travel, as a result of which the extension arm 24 turns in the direction of the arrow D in Figure 5 towards the beam 17. When the locking pin 33 can be passed through the hole in the extension arm 24 and through the hole in the beam 17 the frame portions 1 and 2 can be relatively locked in the transport position, so that the machine can be lifted without the need for further handling. In the embodiment shown in Figures 6 and 7 the cam 35 turns against the slanting part 34A of the locking hook 34, which is thus lifted against the tension of the spring 37 and upon further turning of the frame portions the hook 34 snaps around the cam 35. When the machine is again lowered to the ground for operation, the frame portions 1 and 2 can be unlocked by the driver pulling the cable 38 so that the hook 34 is lifted against the force of the spring 37. By driving the tractor subsequently through a bend the working position is automatically obtained.

Owing to the eccentric position of the pivot shaft 22 with respect to the trestle 11, viewed in the direction of travel C, a transport position can be obtained (Figure 3) in which, as viewed in the direction of travel C, the rake members 4 and 5 have a materially smaller width than in the working position. When the groups of tines 42 are tilted up it is even possible to turn the frame beam 28 still further out of the position shown in Figure 3 in the direction indicated by arrow E so that, viewed in the direction of travel C, the rake members are located substantially one behind the other, part of the rake member 5 being brought below the trestle and below the lifting arms of the tractor. Such a transport position can be obtained thanks to the universal joints 66 and 67 and to the telescopic structure of the transmission shaft 65.

In normal operation the groups of tines 42 occupy the position shown in Figure 8.

The centrifugal force exerted on the groups of tines and on the fastening area thereof slightly urges the lower end of the tine carrier 56 against the top of the plate 45 so that initially the group of tines can deflect unhindered when unevennesses of the ground are encountered. The reactive force produced by the centrifugal force increases in the event of larger deflections.

The group of tines 42 will turn upwards as a whole so that owing to the provision of the described quadrangular hinge structure 50, 51, 54, 55 the tine carrier 56 together with the group of tines 42 will tilt so that the top end of the carrier 56 moves inwardly. With this form of hinge structure, this tilting movement is, however, very slight as compared with a group of tines which is pivotable about a single pivot shaft with respect to the remainder of a rake member. Therefore during an upward displacement, as shown in the side view of Figure 8, the group of tines 42 changes its direction only slightly so that undesirable e;ection of crop is avoided. A further advantage of the quadrangular hinge structure described above is that the tine carrier 56 performs a considerably smaller upward movement during given upward movements of the tips of the tines so that the upward movement of the groups of tines involves relatively lower inertia forces. Owing to the free displaceability of the group of tines the position shown in Figure 8 will be immediately regained by the centrifugal force, whilst the lower end of the carrier 56 serves as a stop with respect to the plate 45.

When the carrier 56 is displaced upwards by hand to an extent such that the pivot shaft 55 arrives at the other side of the plane passing through the center line of the pivot shaft 51 and at right angles to the plate 45, the tine carrier 56 remains stable in the transport position, in which the tines 58 and 59 extend upwardly so that the rake member has a transport width which is appreciably smaller than that in the working position (broken lines in Figure 8). The arms 53 and the cranks 63 then extend inwardly away from the pivot shaft 51. The arms 53 or the cranks 63 and the carrier 56 then move across the space defined by the fork-shaped top end of the support 49.

The centre of gravity of the group of tines 42, the arms 53 and the carrier 56 is then located on the inner side of the pivot shaft 51. When the rake member is driven, each group of tines 42 automatically moves into the working position shown in Figures 8 and 10.

WHAT WE CLAIM IS: - 1. A hay-making machine comprising at least one rake member drivable about an upwardly extending axis of rotation, the rake member having a central part and a plurality of tines, the tines at least in operation being movable with respect to said central part in a direction of height by means of a quadrangular hinge structure by which the tines are connected to said central part.

2. A hay-making machine as claimed in claim 1 and further comprising a frame in which the rake member(s) is/are journalled for rotation about said upwardly extending axis/axes; the frame comprising near its centre with respect to the intended direction of operative travel of the machine a hinge interconnecting parts of the frame and by means of which the machine can be changed over from a working position to a transport position.

3. A hay-making machine as claimed in claim 2, wherein said hinge interconnecting parts of the frame is located, when seen in the intended direction of travel of the machine, at a lateral side of one of the frame parts which are connected by means of this hinge.

4. A hay-making machine as claimed in claim 2 or 3, wherein there is more than one rake member, and wherein during operation the rake members are, in common, freely pivotable with respect to a portion of the frame.

5. A hay-making machine as claimed in claim 2, 3 or 4, wherein said hinge interconnecting parts of the frame comprises a pivot shaft which extends substantially vertically.

6. A hay-making machine as claimed in any one of claims 2 to 5, wherein the frame parts interconnected by said hinge comprise locking means which determine the transport position of the machine.

7. A hay-making machine as claimed in claim 6, wherein said locking means com

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. a transport position can be obtained (Figure 3) in which, as viewed in the direction of travel C, the rake members 4 and 5 have a materially smaller width than in the working position. When the groups of tines 42 are tilted up it is even possible to turn the frame beam 28 still further out of the position shown in Figure 3 in the direction indicated by arrow E so that, viewed in the direction of travel C, the rake members are located substantially one behind the other, part of the rake member 5 being brought below the trestle and below the lifting arms of the tractor. Such a transport position can be obtained thanks to the universal joints 66 and 67 and to the telescopic structure of the transmission shaft 65. In normal operation the groups of tines 42 occupy the position shown in Figure 8. The centrifugal force exerted on the groups of tines and on the fastening area thereof slightly urges the lower end of the tine carrier 56 against the top of the plate 45 so that initially the group of tines can deflect unhindered when unevennesses of the ground are encountered. The reactive force produced by the centrifugal force increases in the event of larger deflections. The group of tines 42 will turn upwards as a whole so that owing to the provision of the described quadrangular hinge structure 50, 51, 54, 55 the tine carrier 56 together with the group of tines 42 will tilt so that the top end of the carrier 56 moves inwardly. With this form of hinge structure, this tilting movement is, however, very slight as compared with a group of tines which is pivotable about a single pivot shaft with respect to the remainder of a rake member. Therefore during an upward displacement, as shown in the side view of Figure 8, the group of tines 42 changes its direction only slightly so that undesirable e;ection of crop is avoided. A further advantage of the quadrangular hinge structure described above is that the tine carrier 56 performs a considerably smaller upward movement during given upward movements of the tips of the tines so that the upward movement of the groups of tines involves relatively lower inertia forces. Owing to the free displaceability of the group of tines the position shown in Figure 8 will be immediately regained by the centrifugal force, whilst the lower end of the carrier 56 serves as a stop with respect to the plate 45. When the carrier 56 is displaced upwards by hand to an extent such that the pivot shaft 55 arrives at the other side of the plane passing through the center line of the pivot shaft 51 and at right angles to the plate 45, the tine carrier 56 remains stable in the transport position, in which the tines 58 and 59 extend upwardly so that the rake member has a transport width which is appreciably smaller than that in the working position (broken lines in Figure 8). The arms 53 and the cranks 63 then extend inwardly away from the pivot shaft 51. The arms 53 or the cranks 63 and the carrier 56 then move across the space defined by the fork-shaped top end of the support 49. The centre of gravity of the group of tines 42, the arms 53 and the carrier 56 is then located on the inner side of the pivot shaft 51. When the rake member is driven, each group of tines 42 automatically moves into the working position shown in Figures 8 and 10. WHAT WE CLAIM IS: -

1. A hay-making machine comprising at least one rake member drivable about an upwardly extending axis of rotation, the rake member having a central part and a plurality of tines, the tines at least in operation being movable with respect to said central part in a direction of height by means of a quadrangular hinge structure by which the tines are connected to said central part.

7. A hay-making machine as claimed in claim 6, wherein said locking means com

prises a locking pin.

8. A hay-making machine as claimed in claim 6, wherein said locking means can be moved into an operative and an inoperative position respectively from the driver seat of a tractor propelling the machine.

9. A hay-making machine as claimed in claim 8, wherein the locking means comprise a hook which is adapted to co-operate with a cam.

10. A hay-making machine as claimed in claim 9, wherein said hook is loaded by a spring which tends to hold the hook in a locking position in the transport position of the machine.

11. A hay-making machine as claimed in claim 10, wherein the hook can be moved into a non-operative position against the pressure of the spring from the driver seat of the tractor.

12. A hay-making machine as claimed in any one of the preceding claims, wherein the pivot axes of the quadrangular hinge structure are located at the corners of a trapezium.

13. A hay-making machine as claimed in any one of the preceding claims, wherein the pivot axes of the quadrangular hinge structure have no common point with the axis of rotation of the rake member concerned.

14. A hay-making machine as claimed in any one of the preceding claims, wherein at least in the normal working position of the tines the plane passing through the lower pair of pivot axes of the quadrangular hinge structure is parallel to the plane passing through the other pair of pivot axes of this structure.

15. A hay-making machine as claimed in claim 14, wherein at least in the normal working position of the tines said planes passing through said pivot axes are normal to the axis of rotation of the rake member concerned.

16. A hay-making machine as claimed in any one of the preceding claims, wherein part of the quadrangular hinge structure forms a tine carrier.

17. A hay-making machine as claimed in any one of the preceding claims, wherein the tines are freely displaceable in a direction of height.

18. A hay-making machine as claimed in claims 16 and 17, wherein the tip of each tine, when moving upwards, covers a larger distance than the tine carrier.

19. A hay-making machine as claimed in claim 17 or 18, wherein the direction of each tine remains substantially the same when the tip of the tine moves upwards in operative conditions.

20. A hay-making machine as claimed in any one of the preceding claims, wherein centrifugal force tends to urge the quadrangular hinge structure against a stop during operation.

21. A hay-making machine as claimed in any one of the preceding claims, wherein a group of two tines in overlying position is arranged on the quadrangular hinge structure.

22. A hay-making machine as claimed in claim 21, wherein the group of tines is capable of moving outwardly and inwardly into a transport position, in which viewed in a direction parallel to the rotary axis of the rake member concerned, the tines are located at least substantially inside the remainder of the rake member and extend upwardly.

23. A hay-making machine as claimed in claim 22, wherein, when a given rotational speed is attained, the group of tines automatically assumes the working position.

24. A hay-making machine as claimed in any one of the preceding claims, wherein the tines are outwardly extending and can be adjusted to and fixed in a substantially radial or in a trailing position relative to the rake member concerned.

25. A hay-making machine as claimed in any one of the preceding claims, wherein the machine comprises an input shaft with which a transmission shaft associated the machine is coupled.

26. A hay-making machine as claimed in claim 25, wherein there are two rake members, and wherein the input shaft is at an angle other than 90" to the plane passing through the axes of rotation of these two rake members.

27. A hay-making machine as claimed in claim 26 or 27, wherein said angle amounts to about 45".

28. A hay-making machine as claimed in claim 26 or 27, wherein the input shaft directly drives one of the rake members.

29. A hay-making machine as claimed in any one of claims 26 to 29, each as appendant directly or indirectly to claim 2, wherein the transmission shaft has a second supporting point located on the frame.

30. A hay-making machine as claimed in any one of claims 26 to 30, wherein the transmission shaft has a telescopic structure and comprises two universal joints.

31. A hay-making machine as claimed in any one of claims 26 to 31 each as appendant directly or indirectly to claim 2, wherein the transmission shaft extends from the input shaft substantially towards said hinge interconnecting parts of the frame.

32. A hay-making machine as claimed in claim 2 or any one of claims 3 to 31 as appendant directly or indirectly to claim 2, wherein, with respect to said intended direction of operative travel, said hinge interconnecting parts of the frame is located eccentrically with respect to a fastening structure for attaching the machine to the three-point lifting device of a tractor.

33. A hay-making machine as claimed in claim 32, wherein at least part of the or each rake member is located, in the transport position, beneath said fastening structure.

34. A hay-making machine as claimed in any one of the preceding claims, wherein beneath the or each rake member there is arranged a ground wheel determining the direction of travel of the machine.

35. A hay-making machine substantially as hereinbefore described and as illustrated in Figures 1 to 5, or Figures 6 and 7, and either Figures 8 and 9 or Figure 10, of the accompanying drawings.