Patent ID: 6152420
Filing Date: 2000-11-28
Classification: B60T

Abstract:
An electromagnetically actuated valve (10) for hydraulic brake systems of a motor vehicle, comprising the following characteristics:a seat valve (53) provided between a pressure fluid inlet (26) and a pressure fluid outlet (33);the seat valve (53) has a closing member (37) and a hollow-conical valve seat (28), into which an inflow bore (29), communicating with the pressure fluid inlet (26), discharges centrally with a diameter (D.sub.1) corresponding substantially to a sealing diameter (D.sub.2) of the valve seat;the closing member (37) is provided with a sharp-edged transition to the face end of a tappet (20);the tappet (20) is engaged by a magnet armature (19) acting closingly on the seat valve (53) and at least indirectly by a restoring spring (23) acting in an opening direction;a closing force (F.sub.F) at the closing member (37), originating in the restoring spring (23), is adapted such that the closing force has a course that decreases monotonously with an increasing valve opening stroke (h);a magnet circuit of the valve (10) is formed such that a magnetic force (F.sub.M) exerted on the magnet armature (19) and transmitted to the closing member (37) is variable in infinitely graduated fashion and has a course that decreases monotonously with an increasing valve opening stroke (h),the magnet armature (19) is disposed in a valve dome (14) that communicates a pressure medium with the pressure outlet (33);the tappet (20) has a longitudinal bore (42), which begins at the closing member (37) and in which a longitudinally movable pin (46) supported at least indirectly on a wall of the valve dome (14) is received, a cross section of the pin corresponding at least approximately to a cross section of the inflow bore (29),a cone angle (.alpha.) of the valve seat (28) is at most 90.degree.;the closing member (37) has the form of a spherical layer; andthe course of the magnetic force (F.sub.M) over the valve opening stroke (h) has a negative slope, which is quantitatively less than that of the course of the spring force.