| 摘要 |
<p>A solenoid has a pole and armature construction wherein, when a predetermined constant current is applied to the solenoid winding, the magnetic force attracting the armature toward the pole decreases as the armature is moved in one direction relative to the pole and the distance the armature is moved is substantially proportional to the current applied to the winding. These operating characteristics are achieved by a solenoid having a field member provided with a pole portion on one end thereof, and having an armature connected to the opposite end for movement relative to the pole portion. The armature is provided with an edge portion which is spaced from the pole portion to define an air gap therebetween. The pole portion produces a magnetic field which exerts a magnetic force on the armature edge portion in one direction relative to the pole portion. The armature edge portion and the pole portion are shaped to control the spacing of the air gap as the armature edge portion is moved in the one direction. By maintaining the air gap spacing substantially uniform, the magnetic force urging the armature edge portion in the one direction toward the pole member decreases as the armature is moved in the one direction, and the armature moves a distance proportional to the current applied to the winding. One application for the present solenoid is as a control device for a pressure regulating valve of the type utilized in vehicle transmissions. In this application, the solenoid controls the valve such that the output pressure of the valve is inversely proportional to the current applied to the winding of the solenoid.</p> |
