CN100362385C - lens driver - Google Patents

Abstract

The present invention relates to a lens driving device which comprises a concave cylindrical ring opening, a base seat used for installing the ring opening, a magnet, a coil, a lens support body, a front side spring and a rear side spring, wherein the magnet and the coil are arranged in the ring opening, the lens support body is arranged in the ring opening, the outer circumferential part of the lens support body is fixed with the coil, and the front side spring and the rear side spring are arranged on the front and the rear parts of the lens support body. The present invention is characterized in that the front and the rear side springs are annular plate springs, a plurality of wrist parts are arranged between the inner and the outer circumferential side end parts of the front and the rear side springs, inserting space are respectively arranged between every two wrist parts, and the inserting space are matched and tightly combined with protrusions of the lens support body. When the coil is not energized, the pre-pressing force of the lens support body toward the base seat is endowed by the front and the rear side springs; the coil generates the electromagnetic force after is energized, and the lens support body is driven to move toward the direction of an optical shaft. The lens driving device of the present invention has the advantage of good impact resistance because of the restoring force of the front and the rear side springs; meanwhile, the impact force in the circumferential direction can be buffered by the arrangement of the wrist parts on the front and the rear side springs, the connection strength of a connecting part of the front and the rear side springs is enhanced, and the present invention also has the advantages of simple structure and easy assembly.

Description

lens driver

technical field

The present invention relates to a lens driving device, in particular to a lens driving device for zooming in a portable compact camera.

Background technique

The structure of the camera lens driving device in the prior art is usually that the lens support body of the camera is connected with the motor shaft through gears. in,

Please refer to Japanese Patent Publication No. 140523 (Heisei 7-140523) patent announcement in 1995. In the above-mentioned patent document, it is described that in the structure in which the lens support body of the camera is connected to the motor shaft through a gear, the motor drives the support body to move At the same time, the pre-pressure of the spring on the lens support will make the lens support return to its original initial position;

Please refer to the patent document published in the publication No. 2003-262779. In the above-mentioned patent document, it is described that in the structure in which the lens support body of the camera is connected to the motor shaft through a gear, when the lens support body moves by a predetermined distance, the spring It is designed as a state of accumulating pressure after being pressed. Due to the fitting between the lens support body, the convex groove and the pin, vibration during movement is prevented.

Although the above-mentioned lens driving device has a certain effect in returning to the original initial position after the lens support is driven by the motor and preventing vibration during movement, there are problems in actual use as follows:

Since the lens driving device is used on a portable small camera, the small camera will be placed in a pocket or a small bag for walking in many occasions, so when walking (not in use) with a small camera, the lens drive The unit is subject to vibrations and shocks from time to time.

The above-mentioned shaking and impact are likely to cause dislocation and damage to the lens support, especially if the lens support is not driven by engagement with cams and pins and by toothing of gears, but is driven by electromagnetic force. In the structure and occasion of the driven lens driving device, since the lens support body is easily caused to vibrate after being shaken and impacted, even if the camera is not in use, the lens support body will still be dislocated and damaged after being shaken and impacted .

Therefore, in the prior art, although the fixed spring is set on the lens support body, with respect to the movement of the lens support body, although it can be considered that the setting of the fixed spring can ease the movement of the lens support body according to the spring preload; The shaking and impact of the driving device do not play a role in alleviating, and its reason is that when the supporting body moves, the preload of the spring just starts to play a role, so although the prior art is provided with a fixed spring on the lens supporting body, it still There is a problem of poor impact resistance.

Contents of the invention

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lens driving device capable of providing the lens driving device with shock resistance characteristics by using a simple structure in a configuration in which a lens support is driven by electromagnetic force.

The purpose of the present invention is achieved like this:

A lens driving device, comprising: a concave cylindrical ring mouth, a base for installing the ring mouth, a magnet and a coil arranged in the ring mouth, a lens support body placed in the ring mouth and fixing the coil on its outer periphery, setting Front side spring and rear side spring before and after the lens support body; its characteristics are:

The front side spring and the rear side spring are ring-shaped leaf springs, and a plurality of wrists are arranged between the inner and outer peripheral ends of the front and rear side springs; There is an insertion space, the insertion space is adapted to the protrusion of the lens support body and closely combined with the protrusion of the lens support body;

When the coil is not energized, the front spring and the rear spring endow the lens support body with a pre-pressure toward the base, so that the lens support body is pressed against the base; after the coil is energized, an electromagnetic force is generated to drive the lens support body toward the base. Move in the direction of the optical axis.

In the above-mentioned lens driving device, wherein, the plurality of arms disposed between the inner peripheral end and the outer peripheral end of the front and rear springs extend along the circumferential direction, and each arm is provided with several Continuous bends.

In the above-mentioned lens driving device, wherein, the arm portion extends in an S-shape in the circumferential direction.

In the above-mentioned lens driving device, wherein, the wrist part has a connection part connected to the inner peripheral end part and a connection part connected to the outer peripheral side end part, and the wrist part is connected to the outer peripheral side end part. A bending portion in the radial direction is formed on the connecting portion.

In the above-mentioned lens driving device, wherein the radially curved portion on the arm portion is convex.

In the above-mentioned lens driving device, wherein the radially curved portion on the arm portion has a concave shape.

In the above-mentioned lens driving device, wherein, the arm portion is formed by bending a connecting portion connected to the outer peripheral end and a connecting portion connected to the inner peripheral end.

In the above-mentioned lens driving device, a gap is formed between the inner peripheral end and the outer peripheral end of the front and rear springs.

Compared with the prior art, the lens driving device of the present invention has the following advantages and positive effects due to the adoption of the above-mentioned technical solution:

1. In the present invention, since the inner peripheral end of the front and rear springs is fixedly connected to the lens support body, the outer peripheral end is fixedly connected to the ring mouth, and the inner peripheral end is in a protruding state, the resultant force of the restoring force of the front and rear springs will The lens support body is pressed against the base, so that even in the occasion of shaking and impact, it is difficult to cause the lens support body to shake, so that it has excellent impact resistance;

2. In the present invention, since the lens support body is pressed to the base by the resultant force of the preload of the front and rear side springs, a large preload is not required for a single spring. It can be seen that the preload of the spring has little influence on the assembly, so that the assembly easy and simple in structure;

3. In the present invention, since the lens support moves through the action of electromagnetic force, it does not need the traditional gear and cam groove fitting structure, so that it not only has high precision but also has a small structure;

4. Since the front and rear side springs of the present invention are ring-shaped leaf springs, the structure is simple and the installation is easy;

5. In the present invention, since the wrists are arranged on the front and rear side springs, the wrists are formed with a continuous bending portion in the circumferential direction, and the impact force in the circumferential direction can be buffered through the expansion and contraction of the bending portion;

6. Since the arms on the front and rear side springs of the present invention are S-shaped, the impact force received in the radial direction and the circumferential direction is eased, so it can be seen that the degree of freedom for mitigating the impact is relatively high;

7. In the present invention, since the wrist is arranged between the inner and outer peripheral ends of the front and rear springs, the connection strength of the connecting portion between the outer and inner peripheral ends of the annular front and rear springs is improved;

8. In the present invention, since the inner and outer peripheral ends of the front and rear side springs are provided with faulted spring plates, the preload of the spring can be increased by reducing the fault during assembly. It can be seen that the lens can be supported by a high preload The body is pressed against the base, thereby further improving impact resistance.

Description of drawings

The purpose, specific structural features and advantages of the present invention can be further understood through the following description of several embodiments of the lens driving device of the present invention in conjunction with the accompanying drawings. Among them, the attached figure is:

1 is a schematic cross-sectional structural view of the first embodiment of the lens driving device of the present invention in the state before driving;

Fig. 2 is a schematic diagram of an enlarged side sectional structure of the front spring in the lens driving device of Fig. 1;

3 is a schematic diagram of an exploded structure of the lens driving device shown in FIG. 1;

4 is a schematic structural view of the front spring in the lens driving device shown in FIG. 3;

Fig. 5 is the structural representation of section B-B section among Fig. 4;

Fig. 6 is a schematic structural view of the C-C section of Fig. 4;

7 is a schematic cross-sectional structural view of the first embodiment of the lens driving device of the present invention in a driving state;

8 is a schematic cross-sectional structural view of the second embodiment of the lens driving device of the present invention during assembly;

9 is a schematic structural view of the front spring in the third embodiment of the lens driving device of the present invention;

10 is a schematic cross-sectional structure diagram of a deformed embodiment of the wrist of the front and rear springs in the lens driving device of the present invention.

Detailed ways

The lens drive device of the present invention is a lens drive device for a variable-focus camera loaded into a mobile phone, and it includes: a cylindrical ring mouth 3, a base 5 that provides the seat and assembly of the ring mouth 3, and is placed in the ring mouth 3 The magnet 13 and the coil 15 are arranged in the ring mouth 3 and the coil 15 is fixed on the outer peripheral portion of the lens support 7 where the lens 20 is placed inside, and the front side spring 9 and the rear side are fixedly arranged on the front and back of the lens support 7. Spring 11; the lens driving device of the present invention drives the lens support body 7 to move toward the optical axis by resisting the preload of the front spring 9 and the rear spring 11 through the electromagnetic force generated by electrifying the coil 15 .

Please refer to FIG. 1 to FIG. 7 , which are schematic structural diagrams of the first embodiment of the lens driving device of the present invention. The lens driving device 1 shown in the first embodiment is a lens driving device for a zoom camera incorporated in a mobile phone (in FIG. 1, the upper and lower ends are the front side and the rear side of the lens driving device, respectively).

1 and 3, the lens driving device 1 of the present invention includes: a cylindrical ring mouth 3, a base 5 for seating and assembling the ring mouth 3, and a lens support body 7 arranged in the ring mouth 3 , the inner peripheral end is fixed to the lens support body 7, the front side spring 9 is arranged on the front side of the lens optical axis direction in the lens support body 7, and the rear side spring 11 is arranged on the rear side of the lens optical axis direction.

The ring mouth 3 is seated on the base 5, and the cross section of the ring mouth 3 is in a concave shape; the magnet 13 is arranged inside the concave ring mouth 3; a coil 15 is also arranged inside the concave ring mouth 3, the The coil 15 is arranged on the inner peripheral side of the magnet 13; the magnet 13 is fixed on the base 5 by the rear gasket 17; the coil 15 is fixed on the outer peripheral portion 7a of the lens support body 7, and the outer peripheral portion 7a of the lens support body 7 enters a concave shape In the ring mouth 3, the outer peripheral portion 7a of the lens support body 7 can move in the concave-shaped gap of the concave-shaped ring mouth 3.

The base 5 is arranged under the ring mouth 3 and surrounds the ring mouth 3 therein, so as to provide the seat and assembly of the ring mouth 3 . The base 5 has an outer peripheral wall 5a adapted to the outer peripheral surface of the ring mouth 3 and a base part 5b vertically connected to the bottom of the outer peripheral wall 5a at the rear side of the ring mouth 3 (that is, the rear side in the optical axis direction of the lens), and the ring mouth 3 is fixed on the base The inner peripheral side of 5; the rear spring 11 is placed on the base 5, wherein the outer peripheral end portion 11b of the rear spring 11 is fixed between the base portion 5b and the rear gasket 17.

In addition, a sensor holder 19 is mounted on the base portion 5 b of the chassis 5 .

The lens support body 7 is arranged on the inner peripheral side of the ring mouth 3, the lens support body 7 is cylindrical, and the lens 20 is arranged inside the lens support body 7, and the lens support body 7 and the lens 20 can be arranged along the optical axis direction. Move freely on the inner peripheral side of the ring mouth 3.

The front gasket 21, the front side spring 9, the frame 23, and the small cap 24 are sequentially arranged on the lens support body 7 and the ring mouth 3.

The front spring 9 is an annular leaf spring structure, and the front spring 9 is designed to have an inner peripheral end 9a and an outer peripheral end 9b; the inner peripheral end 9a of the front spring 9 is clamped on the lens Between the support body 7 and the small cap 24, the outer peripheral end 9b is clamped between the ring mouth 3 and the frame 23; the front gasket 21 is interposed between the outer peripheral end 9b of the front spring 9 and the ring mouth 3 .

The shape of the rear side spring 11 is substantially the same as the above-mentioned front side spring 9, which is an annular leaf spring structure, and the rear side spring 11 is designed to have an inner peripheral end 11a and an outer peripheral end 11b; wherein, the inner The peripheral side end portion 11 a is fixed to the rear end of the lens support body 7 , and the outer peripheral side end portion 9 b is fixed between the base portion 5 b of the chassis 5 and the rear spacer 17 .

Please refer to Fig. 2 in conjunction with Fig. 1 and Fig. 3, the above-mentioned front side spring 9 and rear side spring 11 are flat (see Fig. 3) under the natural state (that is, no applied load state) before installation, but The state after installation is then shown in Figure 2, and Figure 2 is the enlarged side sectional structure schematic diagram of the front side spring (because the shape of the rear side spring 11 is roughly the same as the above-mentioned front side spring 9, the enlargement of the rear side spring 11 is omitted for this reason Schematic). In order to make the inner peripheral end portions 9a and 11a of the front side spring 9 and the rear side spring 11 respectively located in front of the outer same-side end portions 9b and 11b of the front side spring 9 and the rear side spring 11, the front side spring 9 And rear side spring 11 is in the installation state being deformed. Due to the effect of the spring restoring force (preload), the inner peripheral ends 9a, 11a of the front spring 9 and the rear spring 11 always have a preload acting on the base part 5b of the base 5.

Please refer to FIG. 2 and FIG. 4 , FIG. 5 and FIG. 6 in conjunction with FIG. 1 and FIG. 3 . FIG. 2 and FIG. 4 , 5 and 6 are structural schematic diagrams of the front spring in the lens driving device of the present invention.

The structure and function of the front spring 9 and the rear spring 11 will now be described in more detail, but since the structure and function of the front spring and the rear spring 11 are roughly the same, the description of the front spring 9 will be omitted. A detailed description of the structure and function of the rear spring 11.

The front side spring 9 is provided with a plurality of wrists between the inner peripheral end 9a and the outer peripheral end 9b; as for setting several wrists, it depends on the specific situation. In this embodiment, the inner peripheral Three arm parts 25 are provided between the side end part 9a and the outer peripheral end part 9b, and each arm part 25 connects the inner peripheral side end part 9a and the outer peripheral side end part 9b. Each wrist 25 extends along the circumferential direction, and between adjacent wrists 25 and 25, an insertion space 27 (see Fig. 1 and Fig. Figure 4). Since the projection 7b of the lens support 7 is partially inserted into the insertion space 27 of the front spring 9, the lens support 7 is docked with the base portion 5b of the base 5 .

Please refer to FIG. 4 and FIG. 5 . FIG. 5 is a structural schematic diagram of the cross section of the front spring B-B in FIG. 4 . As shown in the figure, the arm portion 25 of the front spring 9 is formed with a continuous curved portion 25c in its circumferential direction, so that the front spring 9 has the function of elastically deforming in the circumferential direction.

Please refer to FIG. 6 in conjunction with FIG. 4 and FIG. 5 . FIG. 6 is a structural schematic diagram of the C-C section of the front spring in FIG. 4 . As shown in Fig. 4 and Fig. 6, the front side spring 9 arm portion 25 forms a radially bent portion 25d on the connection portion 25a connected to the outer peripheral end portion 9b, so as to prevent the The distortion increases the strength.

Similarly, the E-E cross-section shown in FIG. 4 is the same as that in FIG. 6 , so the schematic diagram of the E-E cross-section structure is omitted. The arm portion 25 of the front spring 9 also has a radially bent portion 25d at the connection portion 25b connected to the inner peripheral end portion 9a, thereby preventing distortion and increasing strength.

The assembly steps, working principles, advantages and effects of the lens driving device of the present invention will be described below.

First, the assembly steps of the lens driving device of the present invention are:

(1), install the rear side spring 11 on the lens support body 7, that is, fix the inner peripheral side end 11a of the rear side spring 11 on the lens support body 7, and set the coil 15 on the lens support body 7;

(2), the magnet 13 is fixed in the ring mouth 3, and then the lens support body 7 comprising the lens 20, the coil 15 and the rear side spring 11 arranged on the lens support body 7 are configured into the inside of the ring mouth 3;

(3), install and fix the rear gasket 17 in the base portion 5b of the base 5;

(4), then, insert the projection 7b of the lens support 7 into the insertion space 27 of the rear side spring 11;

(5) Then, between the front spacer 21 and the collar 3, after loading the inner peripheral side end 9a of the front side spring 9, it is fixed with the small cap 24.

(6), at the same time, after the frame 23 is installed on the base 5, the outer peripheral side end 9b is fixed by the frame 23;

(7) Finally, the sensor holder 19 is installed on the base portion 5 b of the chassis 5 .

In this way, the assembly work of the lens driving device of the present invention is completed.

Second, the effect and effect of the lens driving device of the present invention are:

Please refer to Fig. 1 and Fig. 2, when the lens driving device is in the installed state, the respective inner peripheral end portions 9a, 11a of the front side spring 9 and the rear side spring 11 and their outer peripheral end portions 9b, 11b respectively In contrast, the positions of the inner peripheral end portions 9a, 11a are set in a state protruding forward (see FIG. 2 ), and the protrusion 7b of the lens support 7 abuts on the base portion 5b of the base 5. Therefore, the front side spring 9 and the rear side spring 11 each have the effect of a spring restoring force (shown by arrows in FIG. 2 ). It can be seen that the lens support body 7 is pushed to the base portion 5b of the base 5 by the resultant force of the front spring 9 and the rear spring 11; The body 7 itself is also difficult to cause shaking and instability, so it has excellent impact resistance.

In the above case, since the lens supporting body 7 is pressed toward the base portion 5b of the chassis 5 by the resultant force of both the front spring 9 and the rear spring 11, a single spring (the front spring 9 and the rear spring 11) Even if the preload is small, a larger preload can be obtained. And because there is no need for a large preload for a single spring, the preload of the spring has little influence on the assembly, so that the assembly is easy and the structure is simple.

At the same time, because the lens support body 7 is moved by the action of electromagnetic force, there is no traditional structure through which gears and concave-convex grooves are fitted, so not only can avoid the shaking and instability caused by this precision error, and At the same time, miniaturization of the structure is achieved.

Moreover, since the front side spring 9 and the rear side spring 11 are respectively formed with continuous bending portions 25c in the circumferential direction of the respective arm portions 25, even if there is an impact force acting in the circumferential direction, it can be slowed down by the expansion and contraction of the arm portions 25. Impact in the circumferential direction.

In addition, even if an impact force in one radial direction acts on the front side spring 9 and the rear side spring 11, since the connecting parts 25a, 25b between the outer peripheral end and the inner peripheral end of the arm part 25 are formed with curved parts, Therefore, the impact in the radial direction can be slowed down by the expansion and contraction of the wrist portion 25, and the connection strength can also be improved at the same time.

Please refer to Fig. 7, once the coil 15 of the lens drive device of the present invention is supplied with current, as shown in Fig. 7, the lens support body 7 can be moved forward by a certain amount through the action of electromagnetic force to adjust the focal length of the lens. .

Next, other embodiments of the lens driving device of the present invention will be described. In the embodiment to be described below, the parts related to the same function and effect as the above embodiment are denoted by the same symbols, and detailed description thereof is omitted, and the main differences from the above embodiment are described.

Please refer to FIG. 8 , which is a schematic cross-sectional structure diagram of a second embodiment of the lens driving device of the present invention. In this embodiment, when the frame 23 is in the pre-installation state, the front spring 9 is in a natural state (that is, no load state). The difference from the above-mentioned embodiment is that the inner peripheral end 9 of the front spring 9 and the The outer peripheral end 9b is faulted; moreover, in order to reduce the fault between the inner peripheral end 9 and the outer peripheral end 9b when the front spring 9 is installed, in this embodiment, the frame 23 is installed Carry out the fixed installation of front side spring 9 outer peripheral side end 9b again again. It can be seen that, due to the fault that is formed between the inner peripheral end 9a and the outer peripheral end 9b in the front side spring 9, the spring preload (restoring force) after assembly can be further improved, so it can be used with a larger The pre-pressure of the lens support body 7 is pressed to the base portion 5b of the base 5, thereby further improving the impact resistance of the front spring 9.

Please refer to FIG. 9 , which is a schematic structural view of the front spring (and the rear spring) of the third embodiment of the lens driving device of the present invention. In this embodiment, the arm portion 25 of the front spring 9 or the rear spring 11 (the front spring is shown in FIG. 9 ) is formed in an S-shape in the radial direction. Therefore, even when a shaking or impact force is received in the circumferential direction, the radial direction, or the relative oblique direction, the deformation of the S-shaped arm portion 25 can eliminate the force exerted on the circumferential direction, the radial direction, or the relative oblique direction. Impact force is received, thereby improving the degree of freedom of buffering, thus endowing the lens driving device of the present invention with excellent impact resistance.

The lens driving device of the present invention is not limited to the above-mentioned embodiments, and various changes can be made as long as they do not deviate from the gist of the present invention.

For example, on the arms 25 of the front side spring 9 and the rear side spring 11, both a convex radial direction bending portion 25d (as shown in FIG. 6 ) and a concave bending portion as shown in FIG. 10 can be formed. 25e.

As another example, in the third embodiment shown in FIG. 9, as in the first embodiment, the upper curved portion 25c as shown in FIG. The connection parts 25a, 25b of the arm part 25 connected to the inner peripheral end parts 9a, 11a are bent and formed, so that the curved connection parts 25a and 25b dissipate the impact force and improve the impact resistance.

To sum up, the lens driving device of the present invention presses the lens support body to the base due to the combined force of the restoring force of the front and rear springs, thereby having good impact resistance, and the structure is simple and easy to assemble; wrist, so that the impact force in the circumferential direction can be buffered and the connection strength between the outer peripheral end and the inner peripheral end of the front and rear springs is improved; and, since the inner and outer peripheral ends of the front and rear springs are set The split spring plate increases the preload of the spring, thereby further improving impact resistance.

Claims (8)

1. a lens driving device, comprising: concave cylindrical ring mouth (3), the base (5) of ring mouth (3) is installed, the magnetite (13) and coil (13) that are arranged in ring mouth (3) 15), the lens support body (7) that is placed in the ring mouth (3) and the coil (15) is fixed on its outer periphery, the front side spring (9) and the rear side spring that are arranged on the front and back of the lens support body (7) (11); It is characterized by: The front side spring (9) and the rear side spring (11) are ring-shaped leaf springs, and the inner peripheral ends (9a and 11a) and the outer circumference A plurality of wrists (25) are arranged between the side ends (9b and 11b); An insertion space (27) is respectively provided between each arm (25) on the front and rear side springs (9) and (11), and the insertion space (27) is opposite to the protrusion (7b) of the lens support body (7). Fit and tightly combined with the protrusion (7b) of the lens support (7); When the coil (15) is not energized, the front spring (9) and the rear spring (11) give the lens support (7) a preload towards the base (5), so that the lens support (7) Pressed on the base (5); the coil (15) generates electromagnetic force after being energized, driving the lens support (7) to move toward the optical axis. 2. The lens driving device according to claim 1, characterized in that: it is arranged on the inner peripheral end (9a, 11a) and the outer peripheral end (9b) of the front spring (9) and the rear spring (11). , 11b), the plurality of wrists (25) extend along the circumferential direction, and several continuous bending parts are provided on each wrist (25). 3. The lens driving device according to claim 1 or 2, characterized in that, the arm portion (25) extends in an S-shape in the circumferential direction. 4. The lens driving device according to claim 1 or 2, characterized in that: the wrist (25) has a connecting portion (25b) connected to the inner peripheral end (9a) and a connecting portion (25b) connected to the outer peripheral end The connection part (25a) connected to the part (9b), and the wrist part (25) forms a radially bent part on the connection part (25a) connected to the outer peripheral end part (9b). 5. The lens driving device according to claim 1, characterized in that: the bending portion in the radial direction on the wrist portion (25) is convex. 6. The lens driving device according to claim 1, characterized in that the radially curved portion on the wrist (25) is concave. 7. The lens driving device according to claim 1, characterized in that: the wrist (25) is composed of a connecting portion (25a) connected to the outer peripheral end (9b) and a connecting portion (25a) connected to the inner peripheral end ( 9a) The connected connecting portion (25b) is formed by bending. 8. The lens driving device according to claim 1 or 2, characterized in that: the inner peripheral end (9a, 11a) and the outer peripheral end of the front spring (9) and the rear spring (11) The parts (9b, 11b) are on mutually independent planes and connected by the wrist part (25).

Images