GB1455669A - Crop sprayers sterile package - Google Patents

Abstract

1455669 Crop sprayers BERTHOUD SA 13 June 1974 [12 Oct 1973] 26204/74 Heading B2F [Also in Divisions A1 and F1] A crop sprayer comprises an axial flow fan having an annular air outlet (7), Fig. 1 (not shown), containing liquid sipray nozzles (8), the fan blades 17 being rotatable about their radial axes and being connected with a controlling mechanism so that their pitch may be varied. The fan hub comprises two opposed generally cup-shaped members 12, 13 mounted on the fan shaft (2), member 12 having a tubular extension 12' which is keyed on the shaft (2), and member 13 being rotatalble relative to member 12. The members are formed with inturned edges 12a, 13a defining two annular surfaces, each being part of the same spherical surface which engage with the bosses 16 of the blades 17. Inwardly of the edges 12a, 13a the members are provided with teeth 14, 15 respectively which engage with teeth 18, 19 respectively on each base 16. A main actuating shaft 20 is connected to two transverse shafts 23 by worm-and-wheel gears 21, 22 respecitively. Each transverse shaft 23 has screw threaded ends of opposed pitch, and carries threaded sleeves connected to members 24, 25. Member 24 is longer than member 25 and is screwed into a bore (12b), Fig. 3 (not shown), in cup-shaped member 12 through an arcuate slot 13b in member 13. The head of each member 24 is of larger diameter than the width of slot 13b, and members 24 act to retain member 13 against member 12. Shaft 20 carries a slotted head 20a rotation of which, through an aperture (26a) in the end cap (26) of the fan rotor (1), causes members 24 and 25 to be displaced either towards or away from each other, thus causing member 13 to rotate with respect to member 12, thus changing the pitch of fan blades 17. Adjustment of the blade pitch could be by different means e.g. hydraulic.