摘要 |
A cam shaft assembly comprising an elongated shaft including an axis, an end, and an axial bore extending from the end of the shaft and having an end portion adjacent the end of the shaft, a cam located on the shaft and including a cam surface having an eccentric lobe surface and a partially cylindrical surface extending at a uniform radius from the axis, a slot extending axially in the shaft and radially between the axial bore and the cylindrical surface and including a first part in the cam and a second part spaced axially from the first part, an actuating shaft extending in the axial bore, a pin extending radially from the actuating shaft and into the slot for a radial distance greater than the radius of the cylindrical surface, a spring biasing the pin toward the first part of the slot, and a piston subject to fluid pressure, located in the end portion of the axial bore, and engagable with the actuating shaft to axially displace the actuating shaft against the action of the spring so as to locate the pin in the second part of the slot in response to a pressure above a predetermined level. |