Solenoid with variable reluctance plunger
AssigneeRemy Technologies, L.L.C.
InventorsStephen P. Santichen, Michael D. Bradfield
Life of this patent
Estimating the term…
Abstract
A solenoid for a vehicle starter includes at least one coil with a passage extending through the coil in an axial direction. The solenoid further includes a plunger configured to move in the axial direction within the passage. The plunger includes a cylindrical outer surface with a substantially uniform diameter and a circumferential notch. The cylindrical outer surface includes a first portion with a first diameter on one side of the circumferential notch, and a second portion with the first diameter on an opposite side of the circumferential notch. The circumferential notch includes a portion with a second diameter that is less than the first diameter.
Claims20
A solenoid for a vehicle starter, the solenoid comprising:
- a first coil and a second coil with a passage extending through the first coil and the second coil in an axial direction, wherein the first coil is a pull-in coil and the second coil is a hold-in coil;
- and
- a plunger configured to move in the axial direction within the passage, the plunger including a cylindrical outer surface with a substantially uniform diameter and a circumferential notch, the cylindrical outer surface including a first portion with a first diameter on one side of the circumferential notch, and a second portion with the first diameter on an opposite side of the circumferential notch, the circumferential notch including a portion with a second diameter that is less than the first diameter.
A solenoid for a vehicle starter, the solenoid comprising:
- a spool;
- a pull-in coil and a hold-in coil wound on the spool with a passage extending through the spool, the pull-in coil and the hold-in coil;
- and
- a substantially solid plunger positioned within the passage and configured to slide within the passage in an axial direction between a first position and a second position, the plunger including a cylindrical outer surface with a circumferential notch formed in the cylindrical outer surface between a first end and a second end of the cylindrical outer surface;
- and
- a radial wall separated from the plunger by a radial distance, wherein the radial distance varies when the plunger moves from the first position to the second position.
A method of operating a solenoid for a vehicle starter, the solenoid including a pull-in coil and a hold-in coil wound on a spool, the method comprising:
- energizing the pull-in coil of the solenoid;
- moving a substantially solid plunger in an axial direction as a result of energization of the pull-in coil, the substantially solid plunger including a cylindrical outer surface with a substantially uniform diameter and a circumferential notch formed in the cylindrical outer surface between a first end and a second end of the cylindrical outer surface;
- and
- varying magnetic reluctance between the plunger and a solenoid wall as a result of the circumferential notch moving relative to the solenoid wall.
Dependencies are inferred from the claim text.