U.S. patent application number 15/194924 was filed with the patent office on 2017-12-07 for assembly methods of a sma assembly and an ois device.
The applicant listed for this patent is SAE Magnetics (H.K.) Ltd.. Invention is credited to Sidney Shen Kuang CHOU, Jian Feng HE, Yiu Sing HO, Kam Fung YIP.
Application Number | 20170351112 15/194924 |
Document ID | / |
Family ID | 60482199 |
Filed Date | 2017-12-07 |
United States Patent
Application |
20170351112 |
Kind Code |
A1 |
CHOU; Sidney Shen Kuang ; et
al. |
December 7, 2017 |
ASSEMBLY METHODS OF A SMA ASSEMBLY AND AN OIS DEVICE
Abstract
An assembly method of a SMA assembly, includes disposing a lens
holder unit on a SMA unit, the lens holder unit being provided with
a first spring, a lens holder and a coil that are mounted on the
first spring, with the first spring pressed against a mounting
surface of the SMA unit; and bonding the first spring of the lens
holder unit with the mounting surface of the SMA unit. The assembly
process is simplified, the coating and soldering space become big
to facilitate the bonding process, and the joining force between
the SMA unit and the lens holder unit is enhanced.
Inventors: |
CHOU; Sidney Shen Kuang;
(Hong Kong, CN) ; HO; Yiu Sing; (Hong Kong,
CN) ; YIP; Kam Fung; (Hong Kong, CN) ; HE;
Jian Feng; (GuangDong, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SAE Magnetics (H.K.) Ltd. |
Hong Kong |
|
CN |
|
|
Family ID: |
60482199 |
Appl. No.: |
15/194924 |
Filed: |
June 28, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02B 7/023 20130101;
G02B 7/025 20130101; G02B 7/026 20130101; B23K 1/005 20130101; G02B
7/02 20130101; G03B 5/00 20130101; G03B 2205/0076 20130101; G03B
2205/0007 20130101; G03B 5/02 20130101; B23K 1/0016 20130101; G02B
27/646 20130101 |
International
Class: |
G02B 27/64 20060101
G02B027/64; B23K 1/005 20060101 B23K001/005; B23K 1/00 20060101
B23K001/00; G02B 7/02 20060101 G02B007/02; G03B 5/00 20060101
G03B005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 6, 2016 |
CN |
201610393280.6 |
Claims
1. An assembly method of an SMA (Shape Memory Alloy) assembly,
comprising: step (1), disposing a lens holder unit on an SMA unit,
the lens holder unit being provided with a first spring, a lens
holder and a coil, the lens holder and the coil being mounted on
the first spring, the first spring being pressed against a mounting
surface of the SMA unit; and step (2), bonding the first spring of
the lens holder unit with the mounting surface of the SMA unit, and
coating glue from a through hole of the first spring to the
mounting surface of the SMA unit, at least a part of the mounting
surface of the SMA being exposed on the through hole.
2. (canceled)
3. The assembly method according to claim 1, wherein the step (2)
further comprises welding a leg extending from the first spring
with the mounting surface of the SMA unit, the leg being rested on
the mounting surface.
4. The assembly method according to claim 1, before the step (2)
further comprising: disposing a spacer unit on the first spring,
the spacer unit contacting with the mounting surface of the SMA
unit; and bonding the spacer unit with the first spring and the
mounting surface.
5. The assembly method according to claim 4, further comprising
locating the spacer unit near a through hole of the first spring
whereby at least a part of the mounting surface of the SMA unit is
exposed, said bonding the spacer unit with the first spring and the
mounting surface comprising coating glue on the through hole and a
side of the spacer unit.
6. The assembly method according to claim 1, wherein the SMA unit
includes a bottom that is mounted thereon and provided with the
mounting surface.
7. An assembly method of an OIS (Optical Image Stabilizer) device,
comprising: assembling an SMA assembly according to steps (1) and
(2) in claim 1; step (3), bonding a yoke assembly on the SMA
assembly, the yoke assembly being provided with a yoke, a second
spring and magnets being received in the yoke; and step (4),
bonding a cover unit on the yoke assembly, the yoke assembly and
the SMA assembly being covered by the cover unit.
8. (canceled)
9. The assembly method according to claim 7, wherein the step (2)
further comprises welding a leg extending from the first spring
with the mounting surface of the SMA unit, the leg resting on the
mounting surface.
10. The assembly method according to claim 7, before the step (2)
further comprising: disposing a spacer unit on the first spring,
the spacer unit contacting with the mounting surface of the SMA
unit; and bonding the pacer assembly with the first spring and the
mounting surface.
11. The assembly method according to claim 10, further comprising
locating the spacer unit near a through hole of the first spring
whereby at least a part of the mounting surface of the SMA unit is
exposed, said bonding the pacer assembly with the first spring and
the mounting surface comprises coating glue on the through hole and
a side of the spacer unit.
12. The assembly method according to claim 7, wherein the SMA unit
includes a bottom that is mounted thereon and provided with the
mounting surface.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to technical field of optical
image stabilization (OIS) devices for cameras, and more
particularly to assembly methods of a shape memory alloy (SMA)
assembly and an OIS device with the SMA assembly.
BACKGROUND OF THE INVENTION
[0002] With the developments of demands for compact and functional
electronic products such as mobile phones or tablet PC with
cameras, the requirements for the cameras driver become higher,
especially for the optical image stabilization.
[0003] Thus optical image stabilizer (OIS) is applied to camera
lens that requires high quality images, to prevent the image damage
caused by the hand shaking during the use of the camera.
Conventional OIS devices include VCM (voice coil motor) OIS
devices, SMA OIS devices, VCM-SMA OIS devices, piezoelectric OIS
devices, and stepper motor OIS devices, etc. The VCM-SMA OIS
devices become popular due to the quick driving speed, small size,
lower power and higher efficiency.
[0004] Following is the assembly process for this VCM-SMA OIS
device.
[0005] First, assembling the VCM assembly in advance. Concretely,
the conventional VCM assembly includes a yoke assembly and a lens
holder assembly. The yoke assembly includes a yoke, a coil and four
magnets located at four corners of the yoke, these elements are
fixed temporarily by means of UV coating. And then, the yoke
assembly is mounted to the lens holder assembly which includes a
bottom, a lens holder, and four spacers. Concretely, the lens
holder is supported by the bottom, and the four spacers are fixed
temporarily on the bottom. During the assembly, the yoke assembly
is covered on the lens holder assembly, and coating and soldering
are proceeded to form the VCM assembly.
[0006] And then, the VCM assembly is mounted on a SMA unit to form
the VCM-SMA OIS device.
[0007] However, the coating and soldering during the assembly
process for the VCM assembly and the SMA unit are difficult, that
is because coating and soldering positions will be covered by the
yoke when the yoke assembly is covered on the lens holder assembly.
Thus the element bonding for the VCM assembly must be made before
it's mounted to the SMA unit, which causes the process complicated.
During the assembly between the VCM assembly and the SMA unit, the
coating and soldering space between the joining surfaces are very
small due to the yoke cover, which makes the bonding further
difficult. In addition, the coating and soldering must be performed
artificially, and the efficiency and yield are low.
[0008] Thus, there is a need for improved assembly methods of a SMA
assembly and an OIS device to overcome the drawbacks mentioned
above.
SUMMARY OF THE INVENTION
[0009] One aspect of the present invention is to provide an
assembly method of a SMA assembly, thereby the assembly process is
simplified, the coating and soldering space become big to
facilitate the bonding process, and the joining force between the
SMA unit and the lens holder unit is enhanced.
[0010] Another aspect of the present invention is to provide an
assembly method of an OIS device, thereby the assembly process for
the SMA assembly is simplified, the coating and soldering space
become big to facilitate the bonding process, and the joining force
between the SMA unit and the lens holder unit is enhanced.
[0011] To achieve above objectives, an assembly method of a SMA
(Shape Memory Alloy) assembly includes step (1), disposing a lens
holder unit on a SMA unit, the lens holder unit being provided with
a first spring, a lens holder and a coil that are mounted on the
first spring, with the first spring pressed against a mounting
surface of the SMA unit; and step (2), bonding the first spring of
the lens holder unit with the mounting surface of the SMA unit.
[0012] As a preferred embodiment, the step (2) further comprises
coating glue from a through hole of the first spring to the
mounting surface of the SMA unit, with partial mounting surface of
the SMA exposed on the through hole.
[0013] As another preferred embodiment, the step (2) further
comprises welding a leg of the first spring with the mounting
surface of the SMA unit, with the leg rested on the mounting
surface.
[0014] Preferably, before the step (2) the method further includes:
disposing a spacer unit on the first spring, with the spacer unit
contacted with the mounting surface of the SMA unit; and bonding
the spacer unit with the first spring and the mounting surface.
[0015] Preferably, the method further comprises locating the spacer
unit near a through hole of the first spring whereby partial
mounting surface of the SMA unit is exposed, said bonding the
spacer unit with the first spring and the mounting surface
comprises coating glue on the through hole and a side of the spacer
unit.
[0016] Preferably, the SMA unit includes a bottom that is mounted
thereon and provided with the mounting surface.
[0017] An assembly method of an OIS device, includes assembling a
SMA assembly according to steps (1) and (2) mentioned above;
bonding a yoke assembly on the SMA assembly, the yoke assembly
being provided with a yoke, a second spring and magnets accepted in
the yoke; and bonding a cover unit on the yoke assembly, with the
yoke assembly and the SMA assembly covered by the cover unit.
[0018] As a preferred embodiment, the step (2) further comprises
coating glue from a through hole of the first spring to the
mounting surface of the SMA unit, with partial mounting surface of
the SMA exposed on the through hole.
[0019] As another preferred embodiment, the step (2) further
comprises welding a leg of the first spring with the mounting
surface of the SMA unit, with the leg rested on the mounting
surface.
[0020] Preferably, before the step (2) the method further includes
disposing a spacer unit on the first spring, with the spacer unit
contacted with the mounting surface of the SMA unit; and bonding
the spacer unit with the first spring and the mounting surface.
[0021] Preferably, the method further comprises locating the spacer
unit near a through hole of the first spring whereby partial
mounting surface of the SMA unit is exposed, said bonding the
spacer unit with the first spring and the mounting surface
comprises coating glue on the through hole and a side of the spacer
unit.
[0022] Preferably, the SMA unit includes a bottom that is mounted
thereon and provided with the mounting surface.
[0023] In comparison with the prior art, during the assembly method
of the SMA assembly, the coating position and the soldering
position are exposed outside, without covered by additional
elements such as a yoke of a VCM, thus the coating and soldering
space are big, which facilitates the bonding process to improve
assembly efficiency. Furthermore, the coating process can be done
after the lens holder unit is assembled with the SMA unit, thus the
joining force therebetween is enhanced. In addition, because the
first spring of the lens holder unit can be directly mounted on the
mounting surface of the SMA unit, thus a bottom can be reduced by
comparison with the conventional structure, which simplifies the
structures of SMA assembly and the OIS device.
[0024] Other aspects, features, and advantages of this invention
will become apparent from the following detailed description when
taken in conjunction with the accompanying drawings, which are a
part of this disclosure and which illustrate, by way of example,
principles of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The accompanying drawings facilitate an understanding of the
various embodiments of this invention. In such drawings:
[0026] FIG. 1 is a perspective view of a SMA assembly according to
a first embodiment of the present invention;
[0027] FIG. 2 is an exploded perspective view of FIG. 1;
[0028] FIG. 3 shows an assembly process of the SMA assembly;
[0029] FIGS. 4a and 4b shows the coating position between the SMA
unit and the lens holder unit;
[0030] FIGS. 5a and 5b show the soldering position between the SMA
unit and the lens holder unit;
[0031] FIG. 6 shows an assembly process of an IOS device according
to one embodiment of the present invention; and
[0032] FIG. 7 is an exploded perspective view of a SMA assembly
according to a second embodiment of the present invention.
DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS
[0033] Various preferred embodiments of the invention will now be
described with reference to the figures, wherein like reference
numerals designate similar parts throughout the various views. As
indicated above, the invention is directed to assembly methods for
a SMA assembly and an OIS device, thereby the assembly process for
the SMA assembly is simplified, the coating and soldering space
become big to facilitate the bonding process, and the joining force
between the SMA unit and the lens holder unit is enhanced.
[0034] Referring to FIGS. 1 and 2, a SMA assembly 200 according to
a first embodiment of the present invention includes a SMA unit
210, a bottom 220, a lens holder unit 230 and a spacer unit 240,
each of which provides a coaxial center hole. Specifically, the SMA
unit 210 made of shape memory alloy includes a main body 211 and a
mounting surface 212. The bottom 220 is mounted on the mounting
surface 212 of the SMA unit 210 for supporting the lens holder unit
230. It should be noted that, the bottom 220 is optional and can be
omitted in other embodiments. The detailed structures of the SMA
unit 210 are well known the persons skilled in the art, thus are
omitted here. The lens holder unit 230 includes a lens holder 231
for holding lens, such as lens barrel, focus lens or zoom lens,
etc. therein, a coil 232 winding around the lens holder 231, and a
first spring 233 for supporting the lens holder 231 and the coil
232 and protecting the lens barrel, etc.
[0035] Following is the assembly process for this SMA assembly 200
according to the present embodiment.
[0036] First, mounting the bottom 220 on the SMA unit 210.
Specifically, the bottom 220 is disposed on the mounting surface
212 of the SMA unit 210, and is joined by means of coating glue,
for example, so that the bottom 220 can be joined temporarily.
[0037] Second, mounting the lens holder unit 230 on the SMA unit
210. Specifically, the lens holder unit 230 is assembled in
advance, according to the common process, and then the lens holder
unit 230 is disposed on the bottom 220, and alignment is made.
Preferably, in the assembly process of the lens holder unit 230, a
spacer unit 240 can be assembled for enhancing the structure
stability between the first spring 233 and the bottom 220.
Specifically, the spacer unit 240 is supported by the hollowed
first spring 233, with the spacer unit 240 is contacted with the
bottom 220 when the lens holder unit 230 is placed on the bottom
220. Specifically, the first spring 233 of the lens holder unit 230
is pressed against the surface of the bottom 220, and a through
hole 233a of the first spring 233 is aligned with a through hole
220a of the bottom 220. After that, the bonding process between the
lens holder unit 230 and the bottom 220 with the SMA unit 210 is
made.
[0038] More specifically, the bonding process includes coating and
soldering. In the coating process, glue is coated along the through
holes 233a and 220a. Partial mounting surface 212 of the SMA unit
210 is exposed, due to the through holes 233a and 220a. Therefore,
coating in the through holes 233a, 220a can realize the bonding
among the first spring 233, the bottom 220 and the SMA unit 210.
FIGS. 4a and 4b shows the coating position. More preferably, the
spacer unit is located near the through hole 233a. The coating
process includes coating glue in the through hole 233a and the on a
side of the spacer unit 240. In other words, glue coated in the
coating position (the through hole 233a and the side of the spacer
unit 240) will be spread on the first spring 233, the bottom 220,
the SMA unit 210 and the spacer unit 240.
[0039] In the soldering process, the soldering is proceeded between
a leg 233b of the first spring 233 and the bottom 220 of the SMA
unit 210, for achieving a firm connection. Preferably, the leg 233b
of the first spring 233 is rested on the surface of the bottom 220.
Since no additional element is covered on the lens holder unit,
thus soldering between the first spring and the bottom 220 is easy.
FIGS. 5a and 5b show the soldering position.
[0040] By this token, the coating position and the soldering
position are exposed outside, without covered by additional
elements such as a yoke of a VCM, thus the coating and soldering
space are big, which facilitates the bonding process to improve
assembly efficiency. Furthermore, the coating process can be done
after the lens holder unit 230 is assembled with the SMA unit 210,
thus the joining force therebetween is enhanced. In addition,
because the first spring 233 of the lens holder unit 230 can be
directly mounted on the mounting surface 233a of the SMA unit, thus
the bottom can be reduced by comparison with the conventional
structure, which simplifies the structures of SMA assembly and the
OIS device.
[0041] The SMA assembly 200 can be assembled with a yoke assembly
310 and a cover unit 320 to form an IOS device 1. Following is the
assembly process.
[0042] As shown in FIG. 6, concretely, the yoke assembly 310
includes magnets (not shown), a coil (not shown) and a yoke 311
covering the magnets and the coil. The magnets are disposed at
corners of the yoke, and the coil is disposed beside the magnets,
these elements are assembled to form the yoke assembly. And then,
the yoke assembly is bonded to the SMA assembly by means of UV
soldering, and a cover unit 320 is bonded to the yoke assembly by
means of coating and UV soldering for example, to form an IOS
device. It should be noted, the assembly methods for the yoke
assembly 310 and the cover unit 320 can apply the conventional
methods, and the more detailed descriptions are omitted here.
[0043] As another embodiment, as shown in FIG. 7, for reducing the
total thickness of the OIS device, the bottom between the SMA unit
210 and the lens holder unit 230 is removed, thus the lens holder
unit 230 is mounted on the mounting surface 212 of the SMA unit 210
by mean of an insulating layer 250 sandwiched therebetween. Under
this condition, the spacer unit may be canceled. The assembly
processes of the SMA assembly and the OIS device with these
configuration changes are similar to the first embodiment, and the
coating position and the soldering position are exposed outside,
without covered by the yoke 311, thus the coating and soldering
space are big, which facilitates the bonding process to improve
assembly efficiency. Furthermore, the coating process can be done
after the lens holder unit 230 is assembled with the SMA unit 210,
thus the joining force therebetween is enhanced.
[0044] While the invention has been described in connection with
what are presently considered to be the most practical and
preferred embodiments, it is to be understood that the invention is
not to be limited to the disclosed embodiments, but on the
contrary, is intended to cover various modifications and equivalent
arrangements included within the spirit and scope of the
invention.
* * * * *