Interface design of two clamped-together parts
AssigneeDeere & Company
InventorRichard Satzke
Life of this patent
Estimating the term…
Abstract
Two control valve housings each have a longitudinal bore receiving a valve spool. The housings are clamped together by two pairs of bolts located one on each side of the bores. Formed on one of the parts at the interface of the two parts and at opposite sides of each bolt is a pair of roughened surface areas which are prepared by milling or stamping. By means of such a surface preparing method projections are created which are deformed and serve as spacers between the two parts when they are clamped together. The two parts then touch themselves only in the roughened surface areas. Thus, when the two parts are clamped together any distortion in the area of the longitudinal bore is avoided and the valve spool can move in the longitudinal bore, noneffected by the force acting on the two parts.
Claims5
In a spool valve assembly including at least first and second parts, with the first part being a valve housing containing a valve spool, reciprocably mounted in a valve bore, and including a first planar surface paralleling a longitudinal axis of the valve bore and with the second part including a second planar surface disposed in confronting relationship to the first planar surface, a plurality of clamping screws located in respective openings arranged in the first and second parts in perpendicular relationship to the first and second planar surfaces, and a plurality of contact surfaces respectively located adjacent each screw and between the first and second planar surfaces and functioning to keep the first and second planar surfaces separated from each other when the screws are tightened to clamp the first and second parts together, the improvement comprising:
- said contact surfaces respectively being in the form of knurled areas formed on and projecting away from one of and being engaged with the other of the first and second planar surfaces.
The spool valve assembly defined in claim 1 or 8 wherein the height of the knurling from said one of the first and second planar surfaces before tightening the screws is sufficiently greater than any irregularities in the first and second planar surfaces that the latter remain separated after the screws have been tightened to establish a required tension therein and the knurling has been deformed by contact with said other of the first and second planar surfaces.
Dependencies are inferred from the claim text.