| 摘要 |
A pulse width modulated valve comprising a valve housing (26) including a transverse wall (27), an integral extension (28) extending axially from the transverse wall (27) and an peripheral wall (29) extending in a direction opposite to the direction in which the axial extension (28) extends. The solenoid valve also includes a pole member (30) including a pole piece (31) extending axially inwardly of the housing (26), an integral transverse wall (32) extending radially outwardly and connected to the peripheral wall (29). The pole piece (31) has an axial opening (34) therethrough and defines a first conical seat (35). The axial extension (28) of the housing (26) has an axial opening (36) aligned with the opening (34) of the pole. An insert (37) is positioned in an axial opening (36) in the axial extension (28) and defines a second seat (38). A ball (37) is interposed between the first and second seats (35, 38) and has limited movement between the seats. A spring (43) yieldingly urges the ball (39) into engagement with the second seat (38). The insert (37) has portions (40) thereof spaced from the walls of the opening (36) into which the insert (37) extends defining passages (41) to the exterior of the axial extension (28). The housing (26) and pole member (30) define an annular space and a coil (51) assembly is positioned in the annular space, such that when fluid is applied to the axial opening (48) in the insert (37) and the coil (51) si de-energized, the spring means (43) holds the ball (39) against the second seat (38) and prevents flow through the axial opening (48) in the insert (37) while permitting communication between the passages (41) defined by the insert (37) about the ball (39) and second seat (38) through the axial opening (34) in the pole (31) and when the solenoid is energized, the ball (39) is drawn toward the first seat (35) to close communication to the axial opening (34) in the pole (31) and permit flow from the axial opening (48) in the insert (37) past the second seat (38) and through the passages (41) defined by the insert (37) to the exterior of the axial extension (28). |
