Solenoid device

Patent metadata

Field	Value
Publication number	US-10622131-B2
Application number	US-201816154800-A
Country	US
Kind code	B2
Filing date	Oct 9, 2018
Priority date	Oct 11, 2017
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

In a diameter-increasing portion, which includes first to third angle segments, an A-point is defined as an intersection between a radially outer surface of a thin wall portion and the first angle segment, and a B-point is defined as an intersection between a radially outer surface of a thick wall portion and the third angle segment. Radially outer surfaces of the first to third angle segments are located on a radially outer side of a reference conical surface, which is formed by rotating a straight line connecting between the A-point and the B-point about a central axis, throughout an entire range from the A-point to the B-point. A first angle α, a second angle β, a third angle γ and a reference angle θ satisfy relationships of “α≥θ, θ≥γ, θ>β”, and “α≥γ>β”.

First claim

What is claimed is:

1. A solenoid device comprising:
a coil;
a core that is placed on a radially inner side of the coil and has a plunger-receiving hole that extends along a central axis and has a bottom, wherein the core is configured to generate a magnetic attractive force when the coil is energized; and
a plunger that is received in the plunger-receiving hole and is movable in an ON-side moving direction by the magnetic attractive force of the core from an OFF-end, which is defined as a position of the plunger in a deenergized state of the coil, to an ON-end, which is defined as a position of the plunger where the plunger contacts a stopper provided at a bottom surface of the plunger-receiving hole while the ON-side moving direction is defined as a direction from the OFF-end toward the ON-end along the central axis, wherein:
the core includes:
a main attracting portion, which has a relatively large wall thickness and is configured to generate the magnetic attractive force;
a plunger support portion, which slidably supports the plunger; and
one of a thin wall portion and an interrupting portion located between the main attracting portion and the plunger support portion, wherein the thin wall portion has a relatively small wall thickness and is configured to limit a flow of a magnetic flux generated upon energization of the coil, and the interrupting portion interrupts between the main attracting portion and the plunger support portion;

an end part of the main attracting portion, which is located at a side where the one of the thin wall portion and the interrupting portion is placed, includes a diameter-increasing portion that has an outer diameter, which is increased in a plurality of steps in a form of a taper from the one of the thin wall portion and the interrupting portion toward a thick wall portion of the main attracting portion;
the diameter-increasing portion has at least three angle segments that include:
a first angle segment, which includes a taper-start point located at the side where the one of the thin wall portion and the interrupting portion is placed;
a third angle segment, which includes a taper-end point located at a side where the thick wall portion is placed; and
a second angle segment, which is located between the first angle segment and the third angle segment;

in an axial cross-section of the diameter-increasing portion, in a case where the thin wall portion is provided between the main attracting portion and the plunger support portion as the one of the thin wall portion and the interrupting portion, an A-point, which is the taper-start point, is defined as an intersection between a radially outer surface of the thin wall portion and the first angle segment, or in a case where the interrupting portion is provided between the main attracting portion and the plunger support portion as the one of the thin wall portion and the interrupting portion, the A-point, which is the taper-start point, is defined as an intersection between an inner peripheral surface of the plunger-receiving hole and the first angle segment;
in a case where a radially outer surface of the thick wall portion is parallel with the central axis, a B-point, which is the taper-end point, is defined as an intersection between the radially outer surface of the thick wall portion and the third angle segment, or in a case where the radially outer surface of the thick wall portion is not parallel to the central axis while the third angle segment extends in the ON-side moving direction beyond a location of a distal end surface of the plunger held at the ON-end, the B-point, which is the taper-end point, is defined as an intersection between the third angle segment and an imaginary extension line of the distal end surface of the plunger held at the ON-end;
a reference conical surface is defined as an imaginary conical surface that is obtained by rotating a straight line, which connects between the A-point and the B-point, about the central axis; and
the diameter-increasing portion is configured to satisfy both of a range condition and an angle condition;
the range condition is set such that that a radially outer surface of the first angle segment, a radially outer surface of the second angle segment and a radially outer surface of the third angle segment are located along the reference conical surface or on a radially outer side of the reference conical surface throughout an entire range from the A-point to the B-point; and
the angle condition is set as follows:

ti α≥θ, θ≥γ, θ>β
α≥γ>β

where:
α denotes a first angle that is a gradient angle of the first angle segment;
β denotes a second angle that is a gradient angle of the second angle segment;
γ denotes a third angle that is a gradient angle of the third angle segment; and
θ denotes a reference angle that is a gradient angle of the reference conical surface;

a gradient angle of the ON-side moving direction is defined as zero degrees; and
the first angle, the second angle, the third angle and the reference angle are respectively assumed to take a positive value when the first angle segment, the second angle segment, the third angle segment and the reference conical surface are tilted from the ON-side moving direction toward a radially outer side.

2. The solenoid device according to claim 1 , wherein:
a straight terminal point is defined as an intersection between:
one of a rounded corner portion and a chamfered portion, which is formed at a corner between the distal end surface and the outer peripheral surface of the plunger; and
a straight portion of the outer peripheral surface of the plunger, which has a constant outer diameter; and

when the plunger is held at the OFF-end, the straight terminal point is axially placed on a side of a center position of the one of the thin wall portion and the interrupting portion where the distal end surface of the plunger is placed.

3. The solenoid device according to claim 2 , wherein when the plunger is held at the OFF-end, the straight terminal point is axially placed on a side of an axial position of the A-point where the distal end surface of the plunger is placed.

4. The solenoid device according to claim 1 , wherein the second angle is zero degrees.

5. The solenoid device according to claim 1 , wherein the first angle is equal to or larger than 90 degrees.

6. The solenoid device according to claim 1 , wherein in the axial cross-section, at least one of the first angle segment, the second angle segment and the third angle segment is connected to another adjacent one of the first angle segment, the second angle segment and the third angle segment by a corresponding boundary that is connected by a curved line.

Assignees

• Denso Corp

Inventors

• Nagasaki Kanehisa
• Ando Motoyoshi

Classifications

• F16K11/07

  with cylindrical slides · CPC title

• H01F7/13 Primary

  characterised by pulling-force characteristics · CPC title

• H01F7/1607

  Armatures entering the winding · CPC title

• F16K31/0675

  Electromagnet aspects, e.g. electric supply therefor · CPC title

• H01F7/081

  Magnetic constructions · CPC title