摘要 |
<p>An improved power steering valve has a sleeve which circumscribes an inner valve member. An end mill or other rotary cutting tool is utilized to form axially extending grooves inside the valve sleeve. When the end mill is forming the grooves inside the valve sleeve, the axis of rotation of the end mill extends at an acute angle relative to the central axis of the valve sleeve. This results in a groove being formed with axially sloping end surfaces. In order to tend to maximize the compactness of the construction of the valve sleeve, fluid passages or holes are drilled along a sloping path from annular grooves on the outside of the valve sleeve to the sloping end surfaces of the axial grooves inside the valve sleeve. In addition, the compact construction of the valve sleeve is further promoted by forming some of the annular grooves with sloping bottom surfaces so that these grooves are relatively deep. This enables the width of these grooves to be reduced without reducing the capacity of these grooves to accommodate fluid flow.</p> |