Electromagnet, camera lens driving device, and production method of electromagnet

Patent metadata

Field	Value
Publication number	US-2016012950-A1
Application number	US-201514864948-A
Country	US
Kind code	A1
Filing date	Sep 25, 2015
Priority date	Nov 28, 2013
Publication date	Jan 14, 2016
Grant date	—

Abstract

An electromagnet that increases electromagnetic force involved with a current flowing through a coil includes a stacked body including a plurality of base material layers, a coil including an in-plane coil conductor on one main surface of each of the base material layers, and an electrically isolated dummy pattern extending along at least a portion of the coil outside of the in-plane coil conductor on each of the base material layers in a plan view.

First claim

What is claimed is:

1 . An electromagnet comprising:
a base including an insulating base material layer; a coil including a winding-shaped conductive pattern located on the insulating base material layer; and an electrically isolated dummy pattern extending along at least a portion of the coil outside of the coil on the insulating base material layer in a plan view.

2 . The electromagnet according to claim 1 , wherein the base includes a stacked body including a plurality of the insulating base material layers.

3 . The electromagnet according to claim 2 , wherein the dummy pattern is located on the same insulating base material layer as the layer on which the winding-shaped conductive pattern is located.

4 . The electromagnet according to claim 2 , wherein the dummy pattern is located on a plurality of the insulating base material layers.

5 . The electromagnet according to claim 4 , wherein the dummy pattern is located on all of the insulating base material layers on which the winding-shaped conductive pattern is located.

6 . The electromagnet according to claim 2 , wherein a conductor connected to the dummy pattern and extending in a stacking direction of the stacked body is located on the insulating base material layer located above or below the dummy pattern in the stacking direction.

7 . The electromagnet according to claim 6 , wherein
the dummy pattern is located on a plurality of the insulating base material layers; and the conductor extending in the stacking direction connects the dummy patterns located on different ones of the insulating base material layers to each other.

8 . The electromagnet according to claim 2 , wherein
the insulating base material layer is made of thermoplastic resin; the winding-shaped conductive pattern has a winding shape including a plurality of linear portions in a plan view; and a bent portion or a wide portion, which has a larger width than the other linear portions in a direction perpendicular or substantially perpendicular to the direction in which the linear portion extends, in a plan view, is located on at least one of the linear portion of the winding-shaped conductive pattern and the dummy pattern extending along the linear portion.

9 . The electromagnet according to claim 2 , wherein
the stacked body includes a step at which a thickness of the stacked body is different in a stacking direction; and the dummy pattern is located around the step at a portion defining the step where the thickness of the stacked body is larger.

10 . The electromagnet according to claim 2 , wherein the dummy pattern sandwiches at least the coil in a plan view.

11 . The electromagnet according to claim 10 , wherein the dummy pattern encloses the coil in a plan view.

12 . The electromagnet according to claim 11 , wherein the dummy pattern is annular and encloses the coil in a plan view.

13 . The electromagnet according to claim 2 , wherein the insulating base material layer is a flexible resin base material layer.

14 . The electromagnet according to claim 13 , wherein the stacked body includes an opening penetrating in a stacking direction of the stacked body;
a plurality of the coils are provided around the opening; and the stacked body includes a cutaway section extending to an outer edge from the opening at a position where the coils are not provided.

15 . A camera lens driving device comprising:
the electromagnet according to claim 14 ; a camera lens; a lens holder which holds the camera lens and is inserted into the opening of the electromagnet; and a plurality of permanent magnets disposed at positions each overlapped with a plurality of the coils, and moving with electromagnetic force of the electromagnet.

16 . A production method of an electromagnet in which an opening penetrating in a stacking direction is formed on a stacked body formed by stacking a plurality of insulating base material layers made of thermoplastic resin, the method comprising the steps of:
stacking the plurality of insulating base material layers made of thermoplastic resin; forming a plurality of winding-shaped conductive patterns on at least one of the plurality of insulating base material layers so as to surround the opening; forming an electrically isolated dummy pattern on at least one of the plurality of insulating base material layers so as to extend along at least a portion of the winding-shaped conductive pattern at a portion outside of the winding-shaped conductive pattern in a plan view; forming an opening penetrating in the stacking direction and a cutaway section extending to an outer edge from the opening on the plurality of insulating base material layers; and integrating the stacked plurality of insulating base material layers with an application of heat and pressure.

17 . The production method of an electromagnet according to claim 16 , wherein the step of forming the cutaway section includes a step of forming the opening and the cutaway section after the plurality of insulating base material layers are integrated in the integrating step.

18 . The production method of an electromagnet according to claim 16 , wherein the dummy pattern is formed on the same insulating base material layer as the layer on which one of the winding-shaped conductive patterns is formed.

19 . The production method of an electromagnet according to claim 16 , wherein the dummy pattern is formed on at least some of the plurality of the insulating base material layers.

20 . The production method of an electromagnet according to claim 19 , wherein the dummy pattern is formed on all of the insulating base material layers on which the winding-shaped conductive patterns are located.

Assignees

• Murata Manufacturing Co

Inventors

• Nishino Kosuke
• Yosui Kuniaki

Classifications

• H01F5/003

  Printed circuit coils · CPC title

• G03B2205/0007

  Movement of one or more optical elements for control of motion blur · CPC title

• H01F7/20 Primary

  without armatures (cores H01F3/00; coils H01F5/00 {; shaping metal by applying magnetic forces B21D26/14; electromagnets specially adapted for NMR applications G01R33/381}) · CPC title

• H02K3/26

  consisting of printed conductors · CPC title

• G03B2205/0069

  using electromagnetic actuators, e.g. voice coils · CPC title