| 摘要 |
1,242,601. Vehicle steering mechanism. MITSUBISHI JIDOSHA KOGYO K.K. 17 May, 1968 [22 Aug., 1967; 2 Oct., 1967], No. 23724/68. Heading B7H. Lag reducing means for vehicle steering mechanism comprise a piston 62 dividing a bore 64 in a cylinder member 44 into two chambers which are filled with oil and communicate through respective passages 72, 74 with further oil chambers 76, 78 interconnected by a throttle orifice 82. Springs 70 arranged on either side of the piston 62 urge the piston into a central position in the bore 64. The cylinder member 44 is connected by a ball-joint 48 to the drop arm 18 of steering gear 12 actuated by a steering wheel 14. The piston 62 is connected through a rod 60 to the spool 58 of a control valve 30 which regulates supply of pressure fluid from a pump 34 to a steering ram 32. The spool 58 slides in a valve housing 42 carried by a cylinder member 36 which slidably supports the cylinder member 44 and is connected to a link rod 20 connected through tie rods 28 to steerable wheels 24. When the steering wheel 14 is rotated slowly oil is displaced between the chambers 76, 78 through the orifice 82 to permit relative movement between the cylinder member 44 and the piston 62 so that the response of the control valve is delayed. When the steering wheel is rotated rapidly pressure increases on one side of the piston 62 due to restricted flow through the orifice to produce a relatively fast response and a reduction in lag during rapid turns. This effect may be enhanced if the rate of pressure build-up on one side of the piston is increased by providing a vane-type pump 114 which is driven from the steering shaft 16 through gears 110, 112 and arranged to transfer oil from one chamber 76, 78 to the other as the steering wheel is rotated. In another embodiment, Fig. 7 (not shown), the control valve (30a) is actuated in response to axial movement of the steering shaft through lag reducing means (22a) and a lever 144. In a further embodiment, Figs. 8A, 10 (not shown), the lag reducing means (22b) is of the rotary vane-type and not of piston-and-cylinder type. In Fig. 4 (not shown) the lag reducing means is applied to steering mechanism not provided with power assistance. |
