WO2007089240A1 - A voice coil actuator having a flux guide at both ends - Google Patents
A voice coil actuator having a flux guide at both ends Download PDFInfo
- Publication number
- WO2007089240A1 WO2007089240A1 PCT/US2006/004024 US2006004024W WO2007089240A1 WO 2007089240 A1 WO2007089240 A1 WO 2007089240A1 US 2006004024 W US2006004024 W US 2006004024W WO 2007089240 A1 WO2007089240 A1 WO 2007089240A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- cylindrical
- voice coil
- magnetic core
- coil actuator
- magnetic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K41/00—Propulsion systems in which a rigid body is moved along a path due to dynamo-electric interaction between the body and a magnetic field travelling along the path
- H02K41/02—Linear motors; Sectional motors
- H02K41/035—DC motors; Unipolar motors
- H02K41/0352—Unipolar motors
- H02K41/0354—Lorentz force motors, e.g. voice coil motors
- H02K41/0356—Lorentz force motors, e.g. voice coil motors moving along a straight path
Definitions
- the invention is related to the field of voice coils, and in particular, to a voice coil with a flux guide at both ends.
- Voice coils come in many different varieties. Some advanced voice coils use flux focused interleaved magnetic circuits. One example of such a voice coil is disclosed in US patent 5,345,206 entitled “Moving coil actuator utilizing flux-focused interleaved magnetic circuit” issued 9/6/1994 and hereby incorporated by reference.
- FIG. 1 is a cross sectional view of voice coil 100 as disclosed by the above cited patent.
- Voice coil 100 has magnetic core 102 made from a plurality of permanent magnets 106 separated by a plurality of pole pieces 108. The polarity of the permanent magnets is alternated such that the north and south poles of magnets adjacent to the pole pieces face each other.
- Magnetic core 102 is encased in a cylindrical shell 104 that is open on one end and closed on the other end. Magnetic core 102 is attached to the shell 104 at the closed end.
- a cylindrical moving coil 110 is inserted in an air gap between the magnetic coil 102 and the case 104.
- the cylindrical moving coil 110 has at least two sets of windings. The sets of windings have alternating polarities. There is a winding in the cylindrical moving coil 110 corresponding to each one of the plurality of pole pieces in the magnetic core 102.
- Figure 2 is a plot of the magnetic flux in an example embodiment of a coil disclosed in the above cited patent. Flux lines going through the closed end of the shell (at F and G) are more concentrated than the flux lines going from the magnetic pole piece 208 back into the shell near the open end of the shell. This is because the flux at the closed end of the shell is being concentrated by the closed end of the ferro-magnetic shell. The flux traveling through the ferro-magnetic pole piece 208 have to jump an air gap to re-enter the open end of the shell. This lack of flux concentration may cause a loss of power for the magnetic coil. Therefore there is a need for an improved voice coil. SUMMARY OF THE INVENTION
- a voice coil actuator having a magnetic core comprising a plurality of permanent magnets separated by a plurality of pole pieces.
- the polarity of the permanent magnets alternate such that the north and south poles of the magnets adjacent to the pole pieces face each other.
- the magnetic core is encased in a cylindrical shell that has a magnetic flux guide at both ends.
- a cylindrical moving coil is installed in an air gap between the magnetic core and the shell and is captured between the two flux guides. Members are attached to the coil and extend through holes in one of the flux guides.
- FIG. 1 is a cross sectional view of voice coil 100 as disclosed by US patent 5,345,206 (Prior art).
- FIG. 2 is a plot of the magnetic flux in an example embodiment of a coil disclosed by US patent 5,345,206 (Prior art).
- FIG. 3 is a cross sectional view of a voice coil actuator in an example embodiment of the current invention.
- FIG. 4 is a cross sectional view of a voice coil actuator having the first flux guide integrated into the outer shell in an example embodiment of the current invention.
- FIG. 5 is a plot of the magnetic flux in a voice coil actuator in an example embodiment of the current invention.
- FIG. 6a is an isometric view of voice coil 600 in an example embodiment of the invention.
- FIG 6b is a front view of voice coil 600 in an example embodiment of the invention.
- FIG. 7a is a front view of a voice coil with three members in an example embodiment of the invention.
- FIG. 7b is a front view of a voice coil with four members in an example embodiment of the invention.
- FIGS. 1 - 7 and the following description depict specific examples to teach those skilled in the art how to make and use the best mode of the invention. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate variations from these examples that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific examples described below, but only by the claims and their equivalents.
- Figure 3 a is a cross sectional view of voice coil 300 in an example embodiment of the invention.
- Voice coil 300 comprises a cylindrical shell 302, a flux guide 304, a cylindrical moving coil 306 with two members 308 attached to one end, and a cylindrical core comprising a plurality of permanent magnets 312 and two pole pieces 314.
- the cylindrical shell 302 has a closed end and an open end.
- the flux guide 304 is attached to the open end of the shell 302, essentially closing the open end.
- the cylindrical core is centered inside cylindrical shell 302 and attached to the closed end of the shell and held in place by the flux guide 304.
- the cylindrical core is comprised of the two pole pieces captured between the plurality of permanent magnets, with the magnets oriented such that the polarity of the magnets adjacent to each pole piece align (i.e. one pole piece surrounded by two north poles with the next pole piece surrounded by two south poles).
- An air gap is formed between the core and the shell 302.
- the cylindrical moving coil 306 is located in the air gap between the core and the shell 302.
- the two members 308 attached to movable coil 306 extend out through two openings 310 in flux guide 304.
- the cylindrical moving coil 306 has two sets of windings. The two sets of windings have opposite polarities.
- FIG. 3b is a cross sectional view of voice coil 300 in another example embodiment of the invention.
- Voice coil 300 comprises a cylindrical shell 302, two flux guides 304, a cylindrical moving coil 306 with two members 308 attached to one end, and a cylindrical core comprising a plurality of permanent magnets 312 and two pole pieces 314.
- the cylindrical shell 302 has both ends open.
- a flux guide 304 is attached to each end of the shell 302, essentially enclosing the shell.
- the cylindrical core is centered inside cylindrical shell 302 and attached to the two flux guides 304.
- the cylindrical core is comprised of the two pole pieces captured between the plurality of permanent magnets, with the magnets oriented such that the polarity of the magnets adjacent to each pole piece align (i.e. one pole piece surrounded by two north poles with the next pole piece surrounded by two south poles).
- An air gap is formed between the core and the shell 302.
- the cylindrical moving coil 306 is located in the air gap between the core and the shell 302.
- the two members 308 attached to movable coil 306 extend out through two openings 310 in one of the flux guides 304.
- the cylindrical moving coil 306 has two sets of windings. The two sets of windings have opposite polarities.
- an electrical current running through the windings in the cylindrical moving coil 306 located inside the magnetic field generated by the core cause a force to be exerted against the cylindrical moving coil 306.
- the force is transferred from the cylindrical moving coil 306 through the two members 308, attached to the coil, to the outside of the flux guide 304.
- FIG. 4 is a cross sectional view of voice coil 400 in another example embodiment of the invention.
- Voice coil 400 comprises a cylindrical shell 402, two flux guides 404, a cylindrical moving coil 406 with two rods 408 attached to one end, and a cylindrical core comprising a plurality of ring shaped permanent magnets 412 and two ring shaped pole pieces 414.
- the cylindrical shell 402 has both ends open.
- One flux guide 404 is located at each end of the shell 402, essentially enclosing the shell.
- the cylindrical core is centered inside cylindrical shell 402.
- the cylindrical core is comprised of the two ring shaped pole pieces captured between the plurality of ring shaped permanent magnets, with the magnets oriented such that the polarity of the magnets adjacent to each pole piece align (i.e.
- the core, the two flux guides, and the shell are held together by bolt 416 and nut 420.
- An air gap is formed between the core and the shell 402.
- the cylindrical moving coil 406 is located in the air gap between the core and the shell 402.
- the two rods 408 attached to movable coil 406 extend out through two openings 410 in the lower flux guides 404.
- a face plate 422 is attached to the two rods 408.
- the cylindrical moving coil 406 has two sets of windings. The two sets of windings have opposite polarities.
- the cylindrical moving coil has a travel range of approximately distance d, which is the distance between the end of cylindrical moving coil and the lower flux guide, when the cylindrical moving coil is in the up most position.
- d distance between the end of cylindrical moving coil and the lower flux guide, when the cylindrical moving coil is in the up most position.
- an electrical current running through the windings in the cylindrical moving coil 406 located inside the magnetic field generated by the core cause a force to be exerted against the cylindrical moving coil 406.
- the force is transferred from the cylindrical moving coil 406 through the two rods 408, attached to the coil, to the face plate 422 on the outside of the flux guide 404.
- Permanent magnet 424 is attached to face plate 422. Permanent magnet 424 is used to hold or move cylindrical moving coil 406 into the up most position when no current is flowing through the windings on cylindrical moving coil 406.
- a spring may be used instead of permanent magnet 424.
- Figure 5 is a plot of the flux lines from one side of voice coil 400 in one example embodiment of the invention.
- Shell 502 is held between the two flux guides 504 and the cylindrical moving coil 506 is located in the air gap between the core and the shell 502.
- the flux lines on either end of the voice coil are concentrated by the two flux guides 504 attached to either ends of the voice coil. Having the flux lines concentrated at both ends, instead of only one end, can increase the actuating power of the voice coil by as much as 20 percent.
- the examples shown above have only two pole pieces in the core with two corresponding windings in the moving cylindrical coil.
- additional pole pieces may be used with a corresponding increase in the number of windings.
- a core that contains 5 pole pieces would have a cylindrical moving coil having 5 windings where the windings have alternating polarities.
- Figure 6a is an isometric view of a voice coil in an example embodiment of the invention.
- Voice coil 600 has a cylindrical shell 602 with a flux guide 604 attached to one end of the cylindrical shell 602.
- Two circular rods 608 extend out from the inside of cylindrical shell 602 through two holes in flux guide 604.
- Figure 6b is a front view of voice coil 600.
- the two circular rods 608 are placed symmetrically about the center of voice coil 600.
- Voice coil 600 uses two circular rods to transfer the force from the inner moving coil to the outside of the voice coil. Shapes other than circular rods may be used, for example squares, rectangles, circular segments, or the like. The number of rods or member used is also unimportant.
- Figure 7a is a front view of a voice coil with three members in an example embodiment of the invention.
- Figure 7b is a front view of a voice coil with four members in an example embodiment of the invention. Having the rods or members spaced symmetrically around the center of the voice coil minimizes the torque induced into the moving coil inside the voice coil. A voice coil with only one rod attached to the inner moving coil is possible, but may need a stronger suspension for the inner moving coil.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Electromagnetism (AREA)
- Power Engineering (AREA)
- Reciprocating, Oscillating Or Vibrating Motors (AREA)
Abstract
A voice coil actuator having a magnetic core comprising a plurality of permanent magnets separated by a plurality of pole pieces. The polarity of the permanent magnets alternate such that the north and south poles of the magnets adjacent to the pole pieces face each other. The magnetic core is encased in a cylindrical shell that has a magnetic flux guide at both ends. A cylindrical moving coil is installed in an air gap between the magnetic core and the shell and is captured between the two flux guides. Members are attached to the coil and extend through holes in one of the flux guides.
Description
A VOICE COIL ACTUATOR HAVING A FLUX GUIDE AT BOTH
ENDS
BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION
The invention is related to the field of voice coils, and in particular, to a voice coil with a flux guide at both ends.
2. DESCRIPTION OF THE PRIOR ART
Voice coils come in many different varieties. Some advanced voice coils use flux focused interleaved magnetic circuits. One example of such a voice coil is disclosed in US patent 5,345,206 entitled "Moving coil actuator utilizing flux-focused interleaved magnetic circuit" issued 9/6/1994 and hereby incorporated by reference.
Figure 1 is a cross sectional view of voice coil 100 as disclosed by the above cited patent. Voice coil 100 has magnetic core 102 made from a plurality of permanent magnets 106 separated by a plurality of pole pieces 108. The polarity of the permanent magnets is alternated such that the north and south poles of magnets adjacent to the pole pieces face each other. Magnetic core 102 is encased in a cylindrical shell 104 that is open on one end and closed on the other end. Magnetic core 102 is attached to the shell 104 at the closed end. A cylindrical moving coil 110 is inserted in an air gap between the magnetic coil 102 and the case 104. The cylindrical moving coil 110 has at least two sets of windings. The sets of windings have alternating polarities. There is a winding in the cylindrical moving coil 110 corresponding to each one of the plurality of pole pieces in the magnetic core 102.
Figure 2 is a plot of the magnetic flux in an example embodiment of a coil disclosed in the above cited patent. Flux lines going through the closed end of the shell (at F and G) are more concentrated than the flux lines going from the magnetic pole piece 208 back into the shell near the open end of the shell. This is because the flux at the closed end of the shell is being concentrated by the closed end of the ferro-magnetic shell. The flux traveling through the ferro-magnetic pole piece 208 have to jump an air gap to re-enter the open end of the shell. This lack of flux concentration may cause a loss of power for the magnetic coil. Therefore there is a need for an improved voice coil.
SUMMARY OF THE INVENTION
A voice coil actuator having a magnetic core comprising a plurality of permanent magnets separated by a plurality of pole pieces. The polarity of the permanent magnets alternate such that the north and south poles of the magnets adjacent to the pole pieces face each other. The magnetic core is encased in a cylindrical shell that has a magnetic flux guide at both ends. A cylindrical moving coil is installed in an air gap between the magnetic core and the shell and is captured between the two flux guides. Members are attached to the coil and extend through holes in one of the flux guides.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional view of voice coil 100 as disclosed by US patent 5,345,206 (Prior art).
FIG. 2 is a plot of the magnetic flux in an example embodiment of a coil disclosed by US patent 5,345,206 (Prior art). FIG. 3 is a cross sectional view of a voice coil actuator in an example embodiment of the current invention.
FIG. 4 is a cross sectional view of a voice coil actuator having the first flux guide integrated into the outer shell in an example embodiment of the current invention. FIG. 5 is a plot of the magnetic flux in a voice coil actuator in an example embodiment of the current invention.
FIG. 6a is an isometric view of voice coil 600 in an example embodiment of the invention.
FIG 6b is a front view of voice coil 600 in an example embodiment of the invention. FIG. 7a is a front view of a voice coil with three members in an example embodiment of the invention.
FIG. 7b is a front view of a voice coil with four members in an example embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIGS. 1 - 7 and the following description depict specific examples to teach those skilled in the art how to make and use the best mode of the invention. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted.
Those skilled in the art will appreciate variations from these examples that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific examples described below, but only by the claims and their equivalents.
Figure 3 a is a cross sectional view of voice coil 300 in an example embodiment of the invention. Voice coil 300 comprises a cylindrical shell 302, a flux guide 304, a cylindrical moving coil 306 with two members 308 attached to one end, and a cylindrical core comprising a plurality of permanent magnets 312 and two pole pieces 314. The cylindrical shell 302 has a closed end and an open end. The flux guide 304 is attached to the open end of the shell 302, essentially closing the open end. The cylindrical core is centered inside cylindrical shell 302 and attached to the closed end of the shell and held in place by the flux guide 304. The cylindrical core is comprised of the two pole pieces captured between the plurality of permanent magnets, with the magnets oriented such that the polarity of the magnets adjacent to each pole piece align (i.e. one pole piece surrounded by two north poles with the next pole piece surrounded by two south poles). An air gap is formed between the core and the shell 302. The cylindrical moving coil 306 is located in the air gap between the core and the shell 302. The two members 308 attached to movable coil 306 extend out through two openings 310 in flux guide 304. The cylindrical moving coil 306 has two sets of windings. The two sets of windings have opposite polarities. In operation, an electrical current running through the windings in the cylindrical moving coil 306 located inside the magnetic field generated by the core, cause a force to be exerted against the cylindrical moving coil 306. The force is transferred from the cylindrical moving coil 306 through the two members 308, attached to the coil, to the outside of the flux guide 304. Figure 3b is a cross sectional view of voice coil 300 in another example embodiment of the invention. Voice coil 300 comprises a cylindrical shell 302, two flux guides 304, a cylindrical moving coil 306 with two members 308 attached to one end, and a cylindrical core comprising a plurality of permanent magnets 312 and two pole pieces 314. The cylindrical shell 302 has both ends open. A flux guide 304 is attached to each end of the shell 302, essentially enclosing the shell. The cylindrical core is centered inside cylindrical shell 302 and attached to the two flux guides 304. The cylindrical core is comprised of the two pole pieces captured between the plurality of permanent magnets, with the magnets
oriented such that the polarity of the magnets adjacent to each pole piece align (i.e. one pole piece surrounded by two north poles with the next pole piece surrounded by two south poles). An air gap is formed between the core and the shell 302. The cylindrical moving coil 306 is located in the air gap between the core and the shell 302. The two members 308 attached to movable coil 306 extend out through two openings 310 in one of the flux guides 304. The cylindrical moving coil 306 has two sets of windings. The two sets of windings have opposite polarities. In operation, an electrical current running through the windings in the cylindrical moving coil 306 located inside the magnetic field generated by the core, cause a force to be exerted against the cylindrical moving coil 306. The force is transferred from the cylindrical moving coil 306 through the two members 308, attached to the coil, to the outside of the flux guide 304.
Figure 4 is a cross sectional view of voice coil 400 in another example embodiment of the invention. Voice coil 400 comprises a cylindrical shell 402, two flux guides 404, a cylindrical moving coil 406 with two rods 408 attached to one end, and a cylindrical core comprising a plurality of ring shaped permanent magnets 412 and two ring shaped pole pieces 414. The cylindrical shell 402 has both ends open. One flux guide 404 is located at each end of the shell 402, essentially enclosing the shell. The cylindrical core is centered inside cylindrical shell 402. The cylindrical core is comprised of the two ring shaped pole pieces captured between the plurality of ring shaped permanent magnets, with the magnets oriented such that the polarity of the magnets adjacent to each pole piece align (i.e. one pole piece surrounded by two north poles with the next pole piece surrounded by two south poles). The core, the two flux guides, and the shell are held together by bolt 416 and nut 420. An air gap is formed between the core and the shell 402. The cylindrical moving coil 406 is located in the air gap between the core and the shell 402. The two rods 408 attached to movable coil 406 extend out through two openings 410 in the lower flux guides 404. A face plate 422 is attached to the two rods 408. The cylindrical moving coil 406 has two sets of windings. The two sets of windings have opposite polarities. The cylindrical moving coil has a travel range of approximately distance d, which is the distance between the end of cylindrical moving coil and the lower flux guide, when the cylindrical moving coil is in the up most position. In operation, an electrical current running through the windings in the cylindrical moving coil 406 located inside the magnetic field generated by the core, cause a force to be exerted against the cylindrical moving coil 406. The force is transferred from the
cylindrical moving coil 406 through the two rods 408, attached to the coil, to the face plate 422 on the outside of the flux guide 404. Permanent magnet 424 is attached to face plate 422. Permanent magnet 424 is used to hold or move cylindrical moving coil 406 into the up most position when no current is flowing through the windings on cylindrical moving coil 406. In one example embodiment of the invention, a spring may be used instead of permanent magnet 424.
Figure 5 is a plot of the flux lines from one side of voice coil 400 in one example embodiment of the invention. In figure 5 you can see one side of the plurality of permanent magnets 512 surrounding the plurality of pole pieces 514 with the two flux guides 504 on either end with bolt 516 holding the assembly together. Shell 502 is held between the two flux guides 504 and the cylindrical moving coil 506 is located in the air gap between the core and the shell 502. The flux lines on either end of the voice coil are concentrated by the two flux guides 504 attached to either ends of the voice coil. Having the flux lines concentrated at both ends, instead of only one end, can increase the actuating power of the voice coil by as much as 20 percent.
The examples shown above have only two pole pieces in the core with two corresponding windings in the moving cylindrical coil. In other example embodiments of the invention, additional pole pieces may be used with a corresponding increase in the number of windings. For example, a core that contains 5 pole pieces would have a cylindrical moving coil having 5 windings where the windings have alternating polarities.
Figure 6a is an isometric view of a voice coil in an example embodiment of the invention. Voice coil 600 has a cylindrical shell 602 with a flux guide 604 attached to one end of the cylindrical shell 602. Two circular rods 608 extend out from the inside of cylindrical shell 602 through two holes in flux guide 604. Figure 6b is a front view of voice coil 600. The two circular rods 608 are placed symmetrically about the center of voice coil 600. Voice coil 600 uses two circular rods to transfer the force from the inner moving coil to the outside of the voice coil. Shapes other than circular rods may be used, for example squares, rectangles, circular segments, or the like. The number of rods or member used is also unimportant. Figure 7a is a front view of a voice coil with three members in an example embodiment of the invention. Figure 7b is a front view of a voice coil with four members in an example embodiment of the invention. Having the rods or members spaced symmetrically around the center of the voice coil minimizes the torque induced into the
moving coil inside the voice coil. A voice coil with only one rod attached to the inner moving coil is possible, but may need a stronger suspension for the inner moving coil.
Claims
1. A voice coil actuator having a cylindrical magnetic core comprising a plurality of axially magnetized permanent magnets (312) separated by a plurality of pole pieces (314) and where the magnetic polarity of the plurality of permanent magnets (312) alternates, the voice coil actuator having a cylindrical outer shell (302) enclosing the cylindrical magnetic core and forming an air gap between the cylindrical outer shell (302) and the cylindrical magnetic core, the voice coil actuator having a cylindrical moving coil (306) having a corresponding plurality of windings in alternating senses positioned in the air gap, characterized by: two magnetic flux guides (304) with one flux guide attached to each end of the magnetic core and the cylindrical outer shell (302), whereby the moving coil is captured between the two magnetic flux guides (304), at least one member (308) attached to the cylindrical moving coil and extending through an opening (310) in one of the two magnetic flux guides.
2. The voice coil actuator of claim 1 characterized by having one of the flux guides (304) formed as part of the shell (302).
3. The voice coil actuator of claim 1 characterized by having the two flux guides (404) attached to the cylindrical magnetic core and the cylindrical shell (402) by a nut (416) and a bolt (420) where the bolt (420) is positioned through the center of the cylindrical magnetic core.
4. The voice coil actuator of claim 1 characterized by having a plurality of members (308) attached to the cylindrical moving coil and extending through openings (310) in one of the two magnetic flux guides (304).
5. The voice coil actuator of claim 4 characterized by the plurality of members (308) symmetrically space around the cylindrical axis of the cylindrical moving coil (306).
6. The voice coil actuator of claim 4 characterized by having the at least one member (308) in the shape of a cylindrical rod.
7. A method for manufacturing a voice coil actuator by assembling a cylindrical magnetic core comprising a plurality of axially magnetized permanent magnets (312) separated by a plurality of pole pieces (314) and where the magnetic polarity of the plurality of permanent magnets (312) alternates, positioning a cylindrical outer shell (302) to enclose the cylindrical magnetic core thereby forming an air gap between the cylindrical outer shell (302) and the cylindrical magnetic core, positioning a cylindrical moving coil (306) having a corresponding plurality of windings in alternating senses in the air gap, characterized by: attaching at least one member (308) to the cylindrical moving coil(306); attaching two magnetic flux guides(304), one to each end of the magnetic core and the cylindrical outer shell (302), whereby the cylindrical moving coil (306) is captured between the two magnetic flux guides (304) and the at least one member (308) extends through an opening (310) hi one of the two magnetic flux guides (304).
8. The method for manufacturing a voice coil actuator of claim 7 characterized by having the two flux guides (304) attached to the cylindrical magnetic core and the cylindrical shell (302) by a nut (420) and bolt (416) where the bolt (416) is positioned through the center of the cylindrical magnetic core.
9. The method for manufacturing a voice coil actuator of claim 7 characterized by attaching a plurality of members to the cylindrical moving coil and extending through openings in one of the two magnetic flux guides.
10. A voice coil actuator having a cylindrical magnetic core comprising a plurality of axially magnetized permanent magnets (312) separated by a plurality of pole pieces (314) and where the magnetic polarity of the plurality of permanent magnets (312) alternates, the voice coil actuator having a cylindrical outer shell (302) enclosing the cylindrical magnetic core and forming an air gap between the cylindrical outer shell (302) and the cylindrical magnetic core, the voice coil actuator having a cylindrical moving coil (306) having a corresponding plurality of windings in opposite senses positioned in the air gap, characterized by: a means for guiding the magnetic flux at both ends of the voice coil actuator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/US2006/004024 WO2007089240A1 (en) | 2006-02-02 | 2006-02-02 | A voice coil actuator having a flux guide at both ends |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/US2006/004024 WO2007089240A1 (en) | 2006-02-02 | 2006-02-02 | A voice coil actuator having a flux guide at both ends |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2007089240A1 true WO2007089240A1 (en) | 2007-08-09 |
Family
ID=37102210
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/US2006/004024 Ceased WO2007089240A1 (en) | 2006-02-02 | 2006-02-02 | A voice coil actuator having a flux guide at both ends |
Country Status (1)
| Country | Link |
|---|---|
| WO (1) | WO2007089240A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104702084A (en) * | 2013-12-10 | 2015-06-10 | 中国航空工业第六一八研究所 | Cylinder-pole opposite-vertex axial magnetic field structure for increasing voice coil motor thrust constants |
| DE102015210693A1 (en) * | 2015-06-11 | 2016-06-02 | Schaeffler Technologies AG & Co. KG | Plunger coil drive with rectangular cross-section, especially for a short-stroke axis, as well as Kurzhubachse with such a plunger coil drive |
| JP2017093222A (en) * | 2015-11-13 | 2017-05-25 | 山洋電気株式会社 | Coreless linear motor |
| US20180301970A1 (en) * | 2015-10-14 | 2018-10-18 | Festo Ag & Co. Kg | Electric Linear Motor and Testing Device |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3417268A (en) * | 1964-08-25 | 1968-12-17 | Donald A. Lace | Moving coil electro-mechanical device |
| US3743870A (en) * | 1972-06-28 | 1973-07-03 | Ltv Ling Altec Inc | Moving coil linear actuator |
| US5345206A (en) * | 1992-11-24 | 1994-09-06 | Bei Electronics, Inc. | Moving coil actuator utilizing flux-focused interleaved magnetic circuit |
| GB2357193A (en) * | 1999-08-14 | 2001-06-13 | John Pelham Wren | Flux return path for linear motor |
| US20020117904A1 (en) * | 2001-02-27 | 2002-08-29 | Mikhail Godkin | Long stroke linear voice coil actuator with the proportional solenoid type characteristic |
| US20040156526A1 (en) * | 2002-10-28 | 2004-08-12 | Mikhail Godin | Closed-ended linear voice coil actuator with improved force characteristic |
| US20050212363A1 (en) * | 2004-03-24 | 2005-09-29 | Shinano Kenshi Kabushiki Kaisha | Linear actuator |
-
2006
- 2006-02-02 WO PCT/US2006/004024 patent/WO2007089240A1/en not_active Ceased
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3417268A (en) * | 1964-08-25 | 1968-12-17 | Donald A. Lace | Moving coil electro-mechanical device |
| US3743870A (en) * | 1972-06-28 | 1973-07-03 | Ltv Ling Altec Inc | Moving coil linear actuator |
| US5345206A (en) * | 1992-11-24 | 1994-09-06 | Bei Electronics, Inc. | Moving coil actuator utilizing flux-focused interleaved magnetic circuit |
| GB2357193A (en) * | 1999-08-14 | 2001-06-13 | John Pelham Wren | Flux return path for linear motor |
| US20020117904A1 (en) * | 2001-02-27 | 2002-08-29 | Mikhail Godkin | Long stroke linear voice coil actuator with the proportional solenoid type characteristic |
| US20040156526A1 (en) * | 2002-10-28 | 2004-08-12 | Mikhail Godin | Closed-ended linear voice coil actuator with improved force characteristic |
| US20050212363A1 (en) * | 2004-03-24 | 2005-09-29 | Shinano Kenshi Kabushiki Kaisha | Linear actuator |
Non-Patent Citations (1)
| Title |
|---|
| HAGL R ET AL: "DYNAMISCH UND GENAUER", TECHNISCHE RUNDSCHAU, EDITION COLIBRI AG., WABERN, CH, vol. 82, no. 38, 21 September 1990 (1990-09-21), pages 66 - 73,75, XP000161739, ISSN: 1023-0823 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104702084A (en) * | 2013-12-10 | 2015-06-10 | 中国航空工业第六一八研究所 | Cylinder-pole opposite-vertex axial magnetic field structure for increasing voice coil motor thrust constants |
| DE102015210693A1 (en) * | 2015-06-11 | 2016-06-02 | Schaeffler Technologies AG & Co. KG | Plunger coil drive with rectangular cross-section, especially for a short-stroke axis, as well as Kurzhubachse with such a plunger coil drive |
| US20180301970A1 (en) * | 2015-10-14 | 2018-10-18 | Festo Ag & Co. Kg | Electric Linear Motor and Testing Device |
| US10833572B2 (en) * | 2015-10-14 | 2020-11-10 | Festo Se & Co. Kg | Electric linear motor and testing device |
| JP2017093222A (en) * | 2015-11-13 | 2017-05-25 | 山洋電気株式会社 | Coreless linear motor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2850328B1 (en) | Magnetic bearing and method for mounting a ferromagnetic structure around the core of a magnetic bearing | |
| US9325230B2 (en) | Vibration generator | |
| JP7792459B2 (en) | Linear actuator with improved magnetic stability and stripping force | |
| JP3553598B2 (en) | Short stroke single phase electromagnetic actuator with good power / power ratio | |
| US6858954B2 (en) | Reciprocating motor | |
| KR20170094219A (en) | Apparatus and method for magnetizing permanent magnets | |
| JP3945916B2 (en) | Movable iron core type linear motor | |
| EP1320179B1 (en) | Linear motor | |
| WO2007089240A1 (en) | A voice coil actuator having a flux guide at both ends | |
| US6870285B2 (en) | Long stroke linear voice coil actuator with the proportional solenoid type characteristic | |
| US6365993B1 (en) | Round linear actuator utilizing flat permanent magnets | |
| JP2001112228A (en) | Magnet movable linear actuator | |
| CN102185461A (en) | Composite double-coil motor with axial and radial magnets | |
| KR100622057B1 (en) | Zero-electromagnetic magnetic lift | |
| JP2012205451A (en) | Vibration power generator | |
| JP3750127B2 (en) | Voice coil linear motor | |
| KR0152892B1 (en) | Primary stator structure of cylindrical linear motor | |
| JP2012257396A5 (en) | ||
| KR100438951B1 (en) | Structure for laminating stator in reciprocating motor | |
| JP5849415B2 (en) | Linear drive device and manufacturing method thereof | |
| JPH0325372Y2 (en) | ||
| JPS6350819Y2 (en) | ||
| JPH0119372Y2 (en) | ||
| KR100865143B1 (en) | Mover of a reciprocating motor | |
| JP2013051812A (en) | Linear driving device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| 122 | Ep: pct application non-entry in european phase |
Ref document number: 06720304 Country of ref document: EP Kind code of ref document: A1 |