Patent ID: 8939430
Filing Date: 2015-01-27
Classification: B60T,F16K

Abstract:
1. An electromagnetic linear valve comprising: a housing having a dividing portion that divides an interior of said housing into a first fluid chamber and a second fluid chamber, said housing having a through-hole that passes through said dividing portion such that said first and second fluid chambers are to be in communication with each other via said through-hole, said interior of said housing being filled with a working fluid; a plunger movable in an axial direction thereof and located in said first fluid chamber in which said through-hole opens through an opening thereof, said plunger including a first end portion which serves as a valve body and which is seatable on said opening serving as a valve seat; an inlet port provided in said housing and being in communication with said second fluid chamber; an outlet port provided in said housing and being in communication with said first fluid chamber; an elastic body forcing said plunger in a forcing direction that causes said first end portion to be moved toward said opening; and a coil disposed to surround said housing and configured to form a magnetic field that causes said plunger to be moved in a direction that is opposite to the forcing direction, wherein said plunger has a stepped shape, and includes (a) a large outside-diameter portion which is made of a ferromagnetic material and which includes a second end portion constituted by another end portion of said plunger that is opposite to said first end portion of said plunger, and (b) a small outside-diameter portion which is made of a ferromagnetic material and which is contiguous to said large outside-diameter portion so as to be located on a side of said first end portion of said plunger, wherein said housing includes (c) a large inside-diameter portion which is made of a ferromagnetic material and in which said large outside-diameter portion is inserted with a clearance being defined between said large inside-diameter portion and said large outside-diameter portion, and (d) a small inside-diameter portion which is made of a ferromagnetic material and in which said small outside-diameter portion is inserted with a clearance being defined between said small inside-diameter portion and said small outside-diameter portion, said small inside-diameter portion being contiguous to said large inside-diameter portion, and wherein said clearance between said small inside-diameter portion and said small outside-diameter portion is smaller than said clearance between said large inside-diameter portion and said large outside-diameter portion.