Aperture driving device

Abstract

The present invention relates to an appropriate preload to a ball bearing to prevent a rotor from shaking. An aperture driving device according to the present invention uses a wave washer to flexibly press a lower ball supporter so as to provide an appropriate preload, such that the ball bearing can rotate without clearance between an upper ball supporter and the lower ball supporter.

Description

Aperture drive unit

[0001] The present invention relates to an aperture driving device, and more particularly, to an aperture driving device capable of providing an appropriate preload to prevent a ball bearing from shaking between upper and lower ball supports and a rotor.

[0002] Camera devices are devices that capture images or videos of subjects, and are installed on portable devices, drones, vehicles, and other devices. To enhance image quality, camera devices may have image stabilization (IS) functions, such as optical image stabilizers (OIS) and autofocusing (AF), which compensate for or prevent image blurring caused by the user's movements. Camera devices require a configuration capable of adjusting the amount of incident light to suit the surrounding environment or shooting conditions.

[0003] The aperture module controls the movement of the blades to adjust the amount of light entering the aperture. The blades rotate by pivoting, changing the diameter of the aperture. Each component required for the blades' rotation must be precisely meshed and move. For this purpose, a ball bearing, for example, is placed between the upper and lower ball supports and pressed with appropriate pressure to achieve the desired level of friction and movement.

[0004] In the prior art, as illustrated in Fig. 1, in order to provide a preload to a ball bearing, a magnet and a suction yoke are respectively arranged on upper and lower ball supports, which are respectively arranged on the upper and lower sides of the ball bearing. That is, a magnet is arranged on the upper side of the upper ball support, and a metal body having magnetic permeability, such as a suction yoke, is arranged on the lower side of the lower ball support. The lower ball support, which includes the suction yoke, is structured to provide a preload to the ball bearing by a force that is pulled toward the upper ball support by the magnetic force generated by the magnet. This structure may cause the magnetic fields of the driving magnets arranged in the aperture to drive the blade to be mixed and affect each other. An additional structure is required to avoid magnetic interference due to such magnetic fields, which leads to a problem of increased manufacturing costs.

[0005] The present invention provides an appropriate pre-load to a ball bearing to prevent the rotor from shaking.

[0006] Another object of the present invention is to flexibly pressurize the ball supporter when the yoke is assembled so that the ball bearing can drive without play between the ball supporters.

[0007] In order to achieve the above object, the present invention provides an aperture driving device comprising: an upper stator assembly having a second opening overlapping a lens; an upper ball supporter disposed on a lower portion of the upper stator assembly; a rotor assembly having a ball bearing and disposed on a lower portion of the upper ball supporter to rotate; a lower ball supporter disposed on a lower portion of the rotor assembly and engaging with the upper ball supporter to support the ball bearing; a lower stator assembly having a first opening overlapping a lens and having a plurality of pivot pins protruding in the direction of an optical axis in a plurality of regions of an upper surface in contact with the rotor assembly, the lower stator assembly being disposed on a lower portion of the lower ball supporter; and a washer disposed between the lower ball supporter and the lower stator assembly to distribute a pressure applied to the lower ball supporter.

[0008] In the aperture driving device according to the present invention, the rotor assembly comprises a plurality of blades pivoting around the pivot pin; a blade driving unit including a third opening overlapping the lens, the first opening, and the second opening, and a plurality of driving pins protruding in a plurality of areas on the lower surface toward the stator assembly in the direction of the optical axis to provide driving force to the plurality of blades.

[0009] In the aperture driving device according to the present invention, the blades can be arranged in a circular manner in the blade driving section.

[0010] In the aperture driving device according to the present invention, the blade may have a plurality of pivot pin holes coupled to the pivot pin; and a blade slot into which the driving pin is inserted for reciprocating movement.

[0011] In the aperture driving device according to the present invention, the blade driving unit has a plurality of receiving grooves on the outer surface for receiving the ball bearing.

[0012] In the aperture driving device according to the present invention, the blade driving unit may include four receiving grooves arranged at equal distances from each other.

[0013] In the aperture driving device according to the present invention, the upper ball supporter and the lower ball supporter may include a plurality of escape grooves for accommodating a portion of the ball bearing at a portion in contact with the ball bearing.

[0014] In the aperture driving device according to the present invention, the washer may be a wave washer.

[0015] In the aperture driving device according to the present invention, the wave washer may be made of a material that does not require heat treatment and / or a material that has no investment rate.

[0016] In the aperture driving device according to the present invention, the wave washer may be made of any one of stainless steel, aluminum, copper, rubber, and plastic.

[0017] In the aperture driving device according to the present invention, the target load of the wave washer may have a target load in the range of 0.2 g to 0.5 g.

[0018] The aperture driving device according to the present invention uses a wave washer to flexibly press the lower ball support to provide an appropriate pre-load so that the ball bearing can rotate without play between the upper ball support and the lower ball support.

[0019] Figure 1 is an exemplary diagram showing a ball bearing hydraulic structure according to the prior art.

[0020] Fig. 2 is a perspective view showing an aperture driving device according to the present invention.

[0021] Figure 3 is an exploded perspective view of an aperture driving device according to the present invention.

[0022] FIG. 4 is a bottom perspective view showing a state in which a rotor assembly and upper / lower ball supporters are combined in an aperture driving device according to the present invention.

[0023] Figure 5 is an exploded perspective view of the combined state shown in Figure 4.

[0024] Figure 6 is a bottom perspective view showing the rotor assembly illustrated in Figure 5.

[0025] Fig. 7 is a plan perspective view showing the blade drive unit illustrated in Fig. 5.

[0026] Figures 8 and 9 are cross-sectional views taken along line A-A' of Figure 2.

[0027] Figures 10 to 14 are exemplary drawings showing the assembly process of the aperture driving device according to the present invention.

[0028] With respect to the embodiments of the present invention disclosed in the text, specific structural and functional descriptions are merely exemplified for the purpose of explaining the embodiments of the present invention, and the embodiments of the present invention may be implemented in various forms and should not be construed as being limited to the embodiments described in the text.

[0029] The present invention is susceptible to various modifications and takes various forms. Specific embodiments are illustrated in the drawings and described in detail herein. However, this is not intended to limit the present invention to specific disclosed forms, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0030] While terms like "first" and "second" may be used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component."

[0031] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but there may also be other components in between. Conversely, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between. Other expressions that describe the relationship between components, such as "between" and "directly between" or "adjacent to" and "directly adjacent to", should be interpreted similarly. Similarly, "disposed on" can mean disposed directly on the surface of another component or disposed above the surface by a distance.

[0032] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprises" or "has" indicate the presence of a disclosed feature, number, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0033] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted to have a meaning consistent with their meaning in the context of the relevant technology, and shall not be construed in an idealized or overly formal sense unless explicitly defined herein.

[0034] Meanwhile, if a particular embodiment can be implemented differently, the functions or operations specified within a particular block may occur in a different order than specified in the flowchart. For example, two consecutive blocks may actually be performed substantially simultaneously, or, depending on the related functions or operations, the blocks may be performed in reverse order.

[0035] Hereinafter, a lens driving device according to the present invention will be described with reference to the attached drawings. Hereinafter, the lens driving device may be referred to as a lens driving unit, a VCM (Voice Coil Motor), an actuator, a lens moving device, etc., and the term "coil" may be referred to as a coil unit, and the term "elastic member" may be referred to as an elastic unit or a spring. In addition, in the following description, a "terminal" may be referred to as a pad, an electrode, a conductive layer, a bonding portion, etc.

[0036] Hereinafter, an aperture driving device according to the present invention will be described with reference to the attached drawings.

[0037] FIG. 2 is a perspective view showing an aperture driving device according to the present invention, FIG. 3 is an exploded perspective view of an aperture driving device according to the present invention, FIG. 4 is a bottom perspective view showing a state in which a rotor assembly and upper / lower ball supporters are coupled in the aperture driving device according to the present invention, FIG. 5 is an exploded perspective view of the coupled state shown in FIG. 4, FIG. 6 is a bottom perspective view showing the rotor assembly shown in FIG. 5, FIG. 7 is a plan perspective view showing a blade driving unit shown in FIG. 5, and FIGS. 8 and 9 are cross-sectional views taken along line A-A' of FIG. 2.

[0038] An aperture driving device (1000) according to the present invention includes an upper stator assembly (120) having a second opening (OH2) overlapping a lens (not shown), a lower stator assembly (110) having a first opening (OH1) overlapping a lens (not shown), an upper ball supporter (320) disposed inside the upper stator assembly (120), a lower ball supporter (310) disposed inside the lower stator assembly (110), a rotor assembly (400) disposed inside the upper ball supporter (320) and the lower ball supporter (310), and a ball bearing (500) accommodated in a first space (SP1) formed by the upper ball supporter (320), the lower ball supporter (310), and the rotor assembly (400), and a washer (200) accommodated in a second space (SP2) formed by the lower ball supporter (310) and the lower stator assembly (110). Can be.

[0039] At this time, the upper stator assembly (120) and the lower stator assembly (110) can be arranged vertically, and the upper ball supporter (320) and the lower ball supporter (310) can be arranged vertically.

[0040] The lower stator assembly (110) and the upper stator assembly (120) may each be provided with power and control signal connections (610, 620) on one side. The rotor assembly (400) and the lower stator assembly (110) may interact with each other to rotate the blades to change the size of the aperture, thereby acting as an aperture that controls the amount of light incident on the lens.

[0041] The lower stator assembly (110) may have a first opening (OH1) overlapping with the lens and may include a plurality of pivot pins (111) protruding in the direction of the optical axis in a plurality of areas of the upper surface facing the rotor assembly (4000).

[0042] The rotor assembly (400) may include a blade drive unit (420) including a plurality of blades (410) and a plurality of drive pins (422) that provide driving force to the plurality of blades (410).

[0043] A plurality of drive pins (422) may protrude from the lower surface of the blade drive unit (420) toward the lower stator assembly (110) in the direction of the optical axis, and the plurality of drive pins (422) may be arranged in an annular shape centered on the first opening (OH1).

[0044] A plurality of blades (410) can be arranged in an annular manner in the blade drive unit (420) and can form a variable opening.

[0045] Each of the plurality of blades (410) may include a plurality of pivot pin holes (411) into which a pivot pin (111) of the lower stator assembly (110) is inserted, and a blade slot (412) into which a drive pin (422) of the blade drive unit (420) is inserted. Each of the plurality of blades (410) may pivotally move about the pivot pin (111) by the interaction of the fixed pivot pin (111) and the drive pin (422) that rotate together according to the rotation of the rotor assembly (400).

[0046] The blade slot (412) may provide a path through which a plurality of driving pins (422) that rotate around the optical axis may pivot each blade around the pivot pin (111) to form a variable opening for all blades (410). The blade driving unit (420) may have a shape of a disk having a third opening (OH3). The third opening may overlap with the lens, the first opening (OH1), and the second opening (OH2) in the direction of the optical axis. The blade driving unit (420) may include a plurality of magnet insertion holes (423) formed between the third opening (OH3) of the central portion and the outer peripheral surface (OS).

[0047] The blade drive unit (420) may include a plurality of receiving grooves (421) formed on the outer surface (OS). The number of receiving grooves (421) may be four, but this is merely an example and is not necessarily limited thereto. The plurality of receiving grooves (421) may be arranged on the outer surface (OS) at equal intervals from each other.

[0048] The upper ball supporter (310) and the lower ball supporter (320) may be arranged on the outside of the rotor assembly (400). Each of the lower ball supporter (310) and the upper ball supporter (320) may include a plurality of escape grooves (311, 321) formed on an inner surface. The plurality of escape grooves (321) of the upper ball supporter (320) may be arranged on the lower side of the inner surface, and the plurality of escape grooves (311) of the lower ball supporter (310) may be arranged on the upper side of the inner surface. The number of the plurality of escape grooves (311) of the upper ball supporter (320) and the number of the plurality of escape grooves (321) of the lower ball supporter (310) may be the same, and may overlap each other in the optical axis direction.

[0049] The plurality of escape grooves (311) of the upper ball supporter (320) and the plurality of escape grooves (321) of the lower ball supporter (310) may be the same in number as the plurality of receiving grooves (421) of the blade driving unit (420), and may overlap in a direction perpendicular to the optical axis.

[0050] A plurality of escape grooves (311) of the upper ball supporter (320), a plurality of escape grooves (321) of the lower ball supporter (310), and a plurality of receiving grooves (421) of the blade drive unit (420) can form a plurality of first spaces (SP1) having a path extending in the circumferential direction.

[0051] A ball bearing (500) can be accommodated in the first space (SP1). The ball bearing (500) can be arranged on the outside of the rotor assembly (400) and can be supported by a lower ball supporter (310) and an upper ball supporter (320). The ball bearing (500) can be supported by a plurality of escape grooves (311) of the upper ball supporter (320), a plurality of escape grooves (321) of the lower ball supporter (310), and a plurality of receiving grooves (421) of the blade drive unit (420). A ball bearing (500) partially inserted into the receiving groove (421) of the blade driving unit (420) may be surrounded by an upper ball supporter (320) inserted into the inside of the upper stator assembly (120), a lower ball supporter (310) inserted into the inside of the lower stator assembly (110), and a blade driving unit (420) of the rotor assembly (400).

[0052] Fig. 8 is a cross-sectional view taken along line A-A' of Fig. 2. Fig. 9 is a drawing of Fig. 8, in which the ball bearing (500) and the washer (200) are not shown. As shown, the washer (200)

[0053] As illustrated, the washer may be inserted or placed inside the lower stator assembly (110) to support the lower ball supporter (310) while applying preload to the lower portion of the lower ball supporter (310). As the washer (200) supports the lower ball supporter (310), a second space (SP2) may be formed between the lower ball supporter (310) and the lower stator assembly (110). The washer (200) may be placed in the second space (SP2).

[0054] The wave washer (200) arranged in the second space (SP2) can flexibly pressurize the lower ball supporter (310) to provide an appropriate preload to the ball bearing (500). Therefore, the ball bearing (500) can drive without any play between the lower ball supporter (310) and the upper ball supporter (320). That is, when the preload is applied to the ball bearing (500) through the lower ball supporter (310), the internal gap of the space where the ball bearing (500) is arranged becomes negative, so that the difference in elastic deformation according to the contact position between the outer surface of the blade driving part (420) of the rotor assembly (400) and the upper / lower ball supports (310, 320) is reduced.

[0055] The wave washer (200) according to the present invention flexibly pressurizes the lower ball supporter (310) to provide an appropriate preload to the ball bearing (500). Therefore, the ball bearing (500) can be driven without any play between the lower ball supporter (310) and the upper ball supporter (320). That is, when a preload is applied to the ball bearing (500) through the lower ball supporter (310), the internal gap of the space where the ball bearing (500) is arranged becomes negative, so that the difference in elastic deformation according to the contact position between the outer surface of the blade driving part (420) of the rotor assembly (400) and the upper / lower ball supports (310, 320) is reduced. A washer is a round, flat piece placed between two objects, and distributes pressure on the surface between the two parts to increase the fixing force and increase the friction, thereby preventing the connection from loosening.

[0056] The wave washer (200) according to the present invention has a structure in which the center and the periphery alternately rise and fall and can exhibit a spring effect. The wave washer (200) according to the present invention is disposed in a second space (SP2) formed by a ball bearing (500), a lower ball supporter (310), and a lower stator assembly (110) to disperse the pressure applied to the lower ball supporter (310). The wave washer (200) according to the present invention is disposed between the lower ball supporter (310) and the lower stator assembly (110) to provide a preload to the lower ball supporter (310). The purpose of pre-loading the ball bearing (500) through the lower ball supporter (310) is to prevent rotational slip, orbital slip, and rotational slip on the inner / outer ring raceway contact area during rotation and to prevent wear of the ball bearing (500).

[0057] The wave washer according to the present invention is made of a material that does not require heat treatment, and may be made of a material with no magnetic permeability. Therefore, durability is enhanced by preventing rust, and the aperture can operate stably without being affected by the surrounding magnetic field.

[0058] The wave washer (200) according to the present invention may be made of any one of stainless steel, aluminum, copper, rubber, and plastic.

[0059] The target load of the wave washer according to the present invention may have a target load in the range of 0.2g to 0.5g. When the target load is 0.2g or less, the deflection has a value of 0.1g or less, so the preload function cannot be performed. When the target load has a value of 0.5g or more, the deflection exceeds 0.25g, so the pressure applied to the ball bearing is excessive, which may hinder the rotational operation of the ball bearing.

[0060] Figures 10 to 14 are exemplary views showing the assembly process of the aperture driving device according to the present invention. First, as shown in Figure 10, a wave washer (200) is inserted into the inside of the lower stator assembly (110). With the wave washer (200) inserted into the inside of the lower stator assembly (310), as shown in Figure 11, the lower ball supporter (310) is inserted into the inside of the lower stator assembly (110) so that the wave washer (200) is positioned on the lower surface of the lower ball supporter (310). With the lower ball supporter (310) inserted, the rotor assembly (400) is inserted into the inner space of the lower stator assembly (110) so that a plurality of pivot pins (111) formed in the lower stator assembly (110) can be accurately inserted into a plurality of pivot pin holes (411) formed in the blade (410) as shown in FIG. 12. Then, as shown in FIG. 13, the upper ball supporter (320) is placed on the upper portion of the rotor assembly (400) so that the ball bearings (500), partially inserted into the receiving grooves (421) formed in the blade driving part (420) of the rotor assembly (400), can be seated in a plurality of escape grooves (311, 321) formed to be misaligned with each other in the lower ball supporter (310) and the upper ball supporter (320). The assembly of the aperture drive device is completed by combining the upper stator assembly (120) with the ball bearing (500) stably surrounded by the upper / lower ball supporters (310, 320) and the rotor assembly (400).

[0061] As described above, the aperture driving device according to the present invention uses a wave washer to flexibly press the lower ball support to provide an appropriate pre-load, so that the ball bearing can rotate without play between the upper ball support and the lower ball support.

[0062] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0063] The mode for carrying out the invention has been sufficiently described in the above-mentioned “Best mode for carrying out the invention.”

[0064] The embodiment can be used in an aperture drive device that can provide appropriate preload to prevent wobbling between the upper and lower ball supports and the rotor.

Claims

1. Upper stator assembly; An upper ball supporter disposed inside the upper stator assembly; A lower ball supporter positioned below the upper ball supporter; A rotor assembly disposed inside the upper ball supporter and the lower ball supporter; A ball bearing disposed between the upper ball supporter, the lower ball supporter, and the rotor assembly; a lower stator assembly comprising a plurality of pivot pins and positioned below the upper stator assembly; and A washer disposed between the lower ball supporter and the lower stator assembly to disperse the pressure provided to the lower ball supporter, Aperture drive device.

2. In the first paragraph, the rotor assembly, a blade drive unit including a plurality of drive pins; and A plurality of blades including a plurality of holes into which each of the drive pin and the pivot pin is inserted, Aperture drive device.

3. In paragraph 2, The plurality of blades are arranged between the lower stator assembly and the blade drive unit, The plurality of pivot pins protrude from the upper surface of the lower stator assembly, and the plurality of drive pins protrude from the lower surface of the blade drive unit. Aperture drive device.

4. In the second paragraph, the blade driving unit is an aperture driving device including a receiving groove on the outer surface in which at least a portion of the ball bearing is received.

5. An aperture driving device according to claim 1, wherein the upper ball supporter and the lower ball supporter include a plurality of escape grooves for accommodating a portion of the ball bearing.

6. Stator assembly; Rotor assembly positioned inside the stator assembly; A ball supporter disposed between the stator assembly and the rotor assembly; a ball bearing arranged between the ball supporter and the blade drive unit; and including a washer disposed between the stator assembly and the ball supporter; The above ball supporter includes an upper ball supporter and a lower ball supporter positioned below the upper ball supporter to support the ball bearing, The above washer applies pre-load to the lower ball supporter. Aperture drive device.

7. An aperture driving device according to claim 6, wherein the washer is a wave washer.

8. In the 6th paragraph, the washer is an aperture driving device made of a material that does not require heat treatment or has no investment rate.

9. In the 6th paragraph, the washer is an aperture driving device made of any one of stainless steel, aluminum, copper, rubber, and plastic.

10. In the 6th paragraph, the target load of the washer is an aperture drive device having a target load in the range of 0.2 g to 0.5 g.

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