Patent GB-528807-A (GB)
Title: Improvements in and relating to rotary hoeing, cultivating and like agricultural machines
IPC: B62D51/00
Filed: 1939-05-09
Abstract: 528,807. Change-speed and differential gear ; securing wheels on shafts. HOWARD, A. C., and ROTARY HOES, Ltd. May 9, 1939, Nos. 13856/39 and 3724/40. [Class 80 (ii)] [Also in Groups I and XXXI] A rotary tilling machine comprises a gear casing 1 supporting a motor 2, clutch 2a and road wheels 3 at its front, and a tilling implement 4 driven by a chain at its rear. A hood 6 with pivoted extension 7 is provided to protect the operator. A control beam 8 carries handle bars 10 with the motor controls. A depending tube 11 contains a shaft 12 carrying a depthcontrol wheel 13 which is adjustable by a bell crank lever 14. Fig. 2 illustrates variable gearing whereby the implement 4 may be driven at varying forward speeds relatively to the speed of the wheels 3. The motor shaft 17 drives a shaft 19 through bevel gearing 18, 20. Two fixed pinions 21, 22 on shaft 19 are engaged alternatively by sliding gears 23, 24 to give two alternative speeds for the implement drive shaft 25. The gears are slid by two forks carried by a sleeve which is moved along a rod 27 by an arm 28 actuated by a rod 29. The gears are spaced to provide an intermediate neutral position. The shaft 19 drives a lay shaft 31 by pinions 22, 32 with which gears 33 and 34 splined on the lay shaft are adapted to engage alternatively by means of a fork 35 carried by a sleeve 36 also mounted on the rod 27, and moved thereon by an arm 38 actuated by a rod 39. Two speeds and a neutral position are provided for the lay shaft. Two pinions 40, 41 splined on the lay shaft may be slid alternatively into engagement with gears 44, 45 on the road wheel drive shaft 46 to provide two speeds, and the gears 44, 45 form part of a differential device, Fig. 4. Eight different grades of tillage are thus obtained. The pinions 40, 41 are spaced to provide an intermediate neutral position. Pinions 50, 51 mounted on the shaft 46 are driven through the differential and engage gears 52, 53 on the composite road wheel axle 76, The differential comprises a tubular shaft 55 surrounding a solid shaft 56. The gear 44 is free on the shaft 55, and wheels 50, 57 are integral with it. A wheel 58 is keyed to shaft 56, and the wheel 45 is free on a boss formed on wheel 58. Wheels 57, 58 are sun wheels which mesh with planet wheels 60, 61 on shafts 62 fixed at both ends to gears 44, 45. The adjacent ends of the planet wheels mesh with each other in pairs. The device is locked against differential movement when operating on rough ground' by sliding member 68, which is splined on shaft 56, to engage member 67 on the gear 45. The road wheel axle 76 is formed so that its two ends carrying the gears 52, 53 may rotate relatively to each other. A reversing gear is provided for the road wheels, and comprises a pinion 81 on shaft 19 meshing with wheel 82 on stub shaft 83. For reverse, the gear 34 on the lay shaft is slid into engagement with gear 84 fixed to wheel 82. This can only be effected when the implement gearing is in neutral. The implement gear changing mechanism, Fig. 6, comprises a rod 27 with sleeve 26 carrying a fork 23a to which another fork 24a is secured by an arm 86, A lug 87 with slot 88 is formed on the sleeve 26 and is engaged by a pin 89 on an arm 28 carried by an actuating rod 29, which is rotated to move the gears. A sleeve 36 with lug 90 is actuated in a similar manner by an arm 38, and carries a single fork 35 for sliding the gears 33, 34 along the lay shaft, to provide the two speeds for the lay shaft. The gears 40, 41 which provide two speeds for the road wheels, are moved by a fork 42 actuated by a rod 49 in a similar manner. The actuating rods 29, 39, 49 extend upwards through the gear casing and are connected to controls near the handle bars 10. In a modification, the differential device is omitted, and the road wheels are frictionally mounted on the axle to enable them to move differentially. The central part 3, Fig. 14, of the road wheel is clamped against a member 137 secured to the axle 72 by studs 142 acting through springs 141 and a ring 140. In another modification, the end of the shaft 25, opposite to the sprocket 30 is journalled within the gear box, and a shaft projects coaxially with it, and is so geared that it may be engaged by a starting handle or employed as a power takeoff shaft.