-
公开(公告)号：EP0472430A2
公开(公告)日：1992-02-26
申请号：EP91307740.0
申请日：1991-08-22
发明人： Norris, Robert David
CPC分类号： F01L1/08 , F01L1/143 , F01L13/0047
摘要： Valve gear for an internal combustion engine includes a first cam (15) mounted to rotate about a first axis, a second cam (21) mounted to rotate about a second axis which is substantially parallel to the first axis, a phase-change mechanism arranged selectively to vary the phase of one of the cams relative to the other, a valve member (29) movable along a valve axis (30), a spring urging the valve member in a first direction along the valve axis and a cam follower (25) which has first and second contact surfaces (18,24) arranged to be engaged by the first and second cams, respectively, and is arranged to transmit movement from the cams to the valve member but is movable with respect to the valve member. The profile of the first cam (15) includes an ascending portion (202) to move the valve member (29) in a second direction opposite to the first direction and a descending ramp (203) to control movement of the cam follower with respect to the valve member. The profile of the second cam (21) includes a descending portion (200) to control movement of the valve member in the first direction and an ascending ramp (201) to control movement of the cam follower with respect to the valve member. The gradient of the ascending ramp (201) and of the descending ramp (203) are substantially the same over at least part of their length. The phase of the two cams is such that the times for which the ascending and descending ramps contact the follower at least partially overlap at a time during which the valve member is stationary in the closed position. This means that the cam follower moves with respect to the valve member and that the cams remain substantially in contact with the cam follower at all times.
摘要翻译： 用于内燃机的阀齿轮包括安装成围绕第一轴线旋转的第一凸轮（15），安装成围绕基本上平行于第一轴线的第二轴线旋转的第二凸轮（21），布置成 选择性地改变一个凸轮相对于另一凸轮的相位;沿着阀轴线（30）可移动的阀构件（29），沿着阀轴沿第一方向推动阀构件的弹簧和凸轮从动件（25） ），其具有被布置成分别由第一和第二凸轮接合的第一和第二接触表面（18,24），并且被布置成将运动从凸轮传递到阀构件，但是可相对于阀构件移动。 第一凸轮（15）的轮廓包括沿与第一方向相反的第二方向移动阀构件（29）的上升部分（202）和下降斜面（203），以控制凸轮从动件相对于 阀构件。 第二凸轮（21）的轮廓包括用于控制阀构件沿第一方向的运动的下降部分（200）和用于控制凸轮从动件相对于阀构件的运动的上升斜坡（201）。 上升斜坡（201）和下降坡道（203）的梯度在其长度的至少一部分上基本相同。 两个凸轮的相位使得上升和下降斜坡接触从动件的时间至少部分地重叠，在此期间阀构件在关闭位置处是静止的。 这意味着凸轮从动件相对于阀构件移动，并且凸轮始终保持与凸轮从动件基本上接触。
-
公开(公告)号：EP0472430B1
公开(公告)日：1994-02-16
申请号：EP91307740.0
申请日：1991-08-22
发明人： Norris, Robert David
CPC分类号： F01L1/08 , F01L1/143 , F01L13/0047
-
公开(公告)号：EP0472430A3
公开(公告)日：1992-05-27
申请号：EP91307740.0
申请日：1991-08-22
发明人： Norris, Robert David
CPC分类号： F01L1/08 , F01L1/143 , F01L13/0047
摘要： Valve gear for an internal combustion engine includes a first cam (15) mounted to rotate about a first axis, a second cam (21) mounted to rotate about a second axis which is substantially parallel to the first axis, a phase-change mechanism arranged selectively to vary the phase of one of the cams relative to the other, a valve member (29) movable along a valve axis (30), a spring urging the valve member in a first direction along the valve axis and a cam follower (25) which has first and second contact surfaces (18,24) arranged to be engaged by the first and second cams, respectively, and is arranged to transmit movement from the cams to the valve member but is movable with respect to the valve member. The profile of the first cam (15) includes an ascending portion (202) to move the valve member (29) in a second direction opposite to the first direction and a descending ramp (203) to control movement of the cam follower with respect to the valve member. The profile of the second cam (21) includes a descending portion (200) to control movement of the valve member in the first direction and an ascending ramp (201) to control movement of the cam follower with respect to the valve member. The gradient of the ascending ramp (201) and of the descending ramp (203) are substantially the same over at least part of their length. The phase of the two cams is such that the times for which the ascending and descending ramps contact the follower at least partially overlap at a time during which the valve member is stationary in the closed position. This means that the cam follower moves with respect to the valve member and that the cams remain substantially in contact with the cam follower at all times.
-
-
搜索结果
3 条记录 (耗时 0.009 秒)
