Patent GB-1373147-A (GB)
Title: Haymaking appliance
IPC: A01D78/12
Filed: 1972-05-26
Abstract: 1373147 Hay makers MASCHINENFABRIK FAHR AG 26 May 1972 [26 May 1971] 24895/72 Heading A1F A hay making machine comprises at least one driven rotary rake head having a plurality of spokes each carrying a tine carrier which is mounted for rotational but non-linear movement in relation to the rake head and the tines of which in the inoperative position are raised from the ground, are brought into a ground engaging working position by the movement of weights due to centrifugal forces as the head rotates, are tripped to lift them off the ground over a sector of their rotary path, and are returned thereafter to the working position by the weights. A gearing, can track or cable transmits the movement of the weights to the tines and an eccentric disc or a roller lifts the tines over the sector. In a first construction (Fig. 1) the tines 6 are mounted in respective tine carriers 5, which rotate about the axis of a respective spoke 4 when an associated weight 7 moves either radially outwardly due to centrifugal forces or inwardly, to lift the tines over the sector, due to a cable 10 connected between the weight and a freely rotatable disc 12 which eccentric to the head's axis of rotation 2. Springs (not shown) bias the weights 7 inwardly so as to maintain the tines 6 in the inoperative position when the head is stationary. The linear movement of each weight 7 is translated into rotary movement of the associated tine carrier 5 by means of either a racked bar 8 and cooperating gear segment 9 (Fig. 1), or by a helical/ diagonal cam track on the tine carriers surface and a cam follower on a U-shaped weight overlying the top part of the spoke and tine carrier. (Fig. 5 not shown). Alternatively (Fig. 4) a cable 15 is attached to a weight 14 and extends via rollers 16, 17 around the associated tine carrier 5 and thence via roller 18 to the aforementioned eccentric disc 12 with a biasing spring 13 attached to the cable 15 and spoke 4. In a fourth embodiment (Fig. 7 not shown) each tine carrier 5 has a similar helical/diagonal cam track which is engaged by rollers mounted on a bifurcated arm of a bell crank lever whose other arm is connected by rod or cable to a weight displaceably mounted in the end of the associated spoke to the eccentric disc 12 by a cable, and to a biasing spring. In another embodiment (Fig. 12) the tines 50 of each arm 42 are mounted on a tine carrier 49 which rotates about a horizontal shaft 48 held between two plates 45, 46, by means of a helical/diagonal plate 51 riding over a roller 52, when the two plates 45, 46 pivot outwardly about vertical shaft 44 as the head rotates. A cable 10 connects plate 45 to an eccentric disc 12 and operates in conjunction with a biasing spring 54 (as already described). Alternatively (Fig. 9) each tine carrier 34 is rotatably mounted in a respective sleeve 33 and has at its inner end a lever 36 which on engaging a roller 37 trips the tines over a sector of their rotary path. A weight 35 is mounted off centre from each of the tine carriers axis and is connected by a cable 38 to the uppermost end of the lever 36 on the tine carrier leading by 90‹ with respect to the direction of rotation of the rake head (Fig. 10 not shown). Stop pieces 39-41 limit the rotation of each carrier about its own axis. When the rake head rotates, the weights 35 move outward and via cable 38 and associated levers 36 rotate the tines into the working position. When the head is stationary a torque is created by gravity acting on the off centre weights 35 which rotates the carriers 34 about their own axes and hence lifts the tines into the inoperative position. Reference has been directed by the comptroller to Specifications 1241745 and 1261476.