A new type of bent FPC spring structure

Abstract

The present invention belongs to the technical field of miniature cameras, and discloses a novel bent FPC spring sheet structure, which is arranged in a miniature camera with a sensor anti-shake function, and includes an elastic and conductive spring sheet body, wherein the elastic body includes an outer portion and a central portion for supporting a sensor, wherein the central portion has at least two connecting portions extending outward and connected to the outer portion, and the outer portion has a plurality of elastic wire arms that are turned up to one side and are not parallel to the plane where the central portion is located, and the elastic wire arms are connected to an external fixed structure. The present invention provides a novel bent FPC spring sheet structure to solve this problem. When the elastic K value in the X / Y direction is appropriate, the present invention can greatly improve the elastic K value in the Z direction, and can greatly reduce the posture difference in Sensor‑Shift and the displacement in the Z direction.

Description

Technical Field

[0001] The invention belongs to the technical field of miniature cameras, and in particular relates to a novel bent FPC spring sheet structure. Background Art

[0002] The demand for taking photos is increasing in mobile phones and other terminal devices, and there is a demand for more photo functions and better cameras in these mobile terminal devices. In order to improve the shooting performance of existing mobile terminal devices, many terminal devices will adopt multiple solutions to upgrade their internal structures. In addition to data processing, the improvement of photo hardware is also a major improvement direction. However, due to the volume limitations of mobile terminal devices, the camera module cannot achieve equivalent performance improvements by expanding the volume. It is necessary to design more efficient functional components in a limited space, which is the improvement idea of ​​the existing technology.

[0003] There are many ways to improve image quality, among which autofocus is a necessary function of existing cameras, which is mainly achieved by realizing axial controllable movement of its lens module. In recent years, OIS optical image stabilization has also been the main improvement direction for mobile phones and mobile terminals to improve image quality. The so-called OIS optical image stabilization is to achieve motion compensation for sensors or lens modules through internal actuating components, sense the motion parameters of the entire terminal device through gyroscopes and other devices, and provide equivalent swing amplitude through actuating components to improve imaging stability and avoid "blurring" photos.

[0004] Optical image stabilization includes lens image stabilization and sensor image stabilization. In order to reduce the volume of the entire module, or to set up larger sensors or other components while keeping the volume unchanged, existing micro cameras have gradually begun to apply sensor image stabilization technology. In the existing sensor image stabilization technology, most of them use FPC springs to carry sensors, and at the same time play the role of transmitting image signals and balancing magnetic field forces. Ideally, when the camera sensor (X / Y direction) is optically image stabilized, the sensor cannot be displaced in the Z direction, otherwise it will affect the photo effect; and the displacement of the sensor in the Z direction depends on the elastic K value of the FPC spring in the Z direction. Therefore, under the condition of ensuring that the elastic K value in the X / Y direction is appropriate, the elastic K value of the FPC spring in the Z direction should be as large as possible. However, due to the planar structure of the existing FPC spring, it is relatively soft in the Z direction, and it is also difficult to increase the K value in the Z direction. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a spring clip structure used in a sensor anti-shake module, which has a three-dimensional spatial structure and can not only provide elastic restoring force in the X / Y directions, but also make up for the fact that the existing spring clip cannot effectively provide elastic restoring effect in the Z direction.

[0006] The technical solution adopted by the present invention is:

[0007] In the first aspect, the present invention provides a novel bent FPC spring sheet structure, which is arranged in a miniature camera with a sensor anti-shake function, and includes a spring sheet body that is elastic and conductive, wherein the elastic body includes an outer portion and a central portion for supporting the sensor, wherein the central portion has at least two connecting portions extending outward and connected to the outer portion, and the outer portion has a plurality of elastic wire arms that are flipped to one side to form an elastic wire arm that is not parallel to the plane where the central portion is located, and the elastic wire arms are connected to an external fixed structure.

[0008] First of all, the shrapnel in the present invention is an elastomeric structure arranged in the optical image stabilization module of the miniature camera. This structure can realize accurate electric control under the premise of a sufficiently small volume, wherein the shrapnel as a limiting structure is a core functional component. Since the existing sensor anti-shake module sets the sensor on the shrapnel, and the shrapnel has two connected parts, one part is connected to the sensor, and the other part is connected to the external fixed structure, and the fixed structure is generally the shell of the camera module. The two parts or the entire shrapnel are elastic, which can make the two parts move relative to each other to a certain extent, and through its own elasticity, the entire sensor can only move within a certain range and speed with the shell.

[0009] An electromagnetic structure connected to the sensor is also provided in the camera module, which can be passed with a directional current to make it move regularly. The electromagnetic structure controls the sensor to move relative to the lens module, thereby achieving the effect of motion compensation. The movement mode in the prior art is only to translate or fold along the X / Y axis in the direction of the plane where the sensor is located, and the Z axis (i.e., perpendicular to the sensor plane direction) is not required, which results in the spring sheet structure being unable to provide a good elastic constraint effect when the entire sensor moves in the Z axis direction. In order to improve the elastic constraint force in the Z axis direction, the spring sheet in the present invention is first cut on a whole sheet structure to form a spring sheet shape, and then the excess material is removed and folded once or multiple times, so that the peripheral part surrounding the outside of the central part forms multiple elastic wire arms. The peripheral part and the central part are both sheet structures, and the angle mentioned in the above content is the angle between the planes where the larger surfaces of the two parts are located. After the peripheral part is folded, it forms a certain elastic area in the Z axis direction, and provides the sensor with stable elastic restrictions in multiple directions by cooperating with the central part.

[0010] In combination with the first aspect, the present invention provides a first implementation manner of the first aspect, wherein the angle between the elastic wire arm and the plane where the central portion is located is in the range of 60-90°.

[0011] It is worth noting that the above angle range is the optimal range value, and only the minimum spatial angle between the two surfaces is used as the limiting range, so the maximum range value of the angle is 0-90°.

[0012] In combination with the first aspect, the present invention provides a second implementation of the first aspect, wherein the peripheral portion has a pin portion initially extending toward the central portion, and the pin portion is folded outward for the first time along with the elastic wire arm portion, and then folded a second time to form a state facing the outside of the peripheral portion.

[0013] It is worth noting that the entire spring sheet is not only used to support the sensor, but also integrated with the circuit. The central part has multiple contacts connected to the bottom of the sensor. The entire spring sheet body is arranged with multiple independent circuits, and is connected to the outside through the pin portion provided on the peripheral part. Since the pin portion is an integrated extension end of the entire spring sheet body, and the spring sheet body is formed by cutting a sheet body, when the peripheral part is folded to form the elastic wire arm, the pin portion will also be folded and coplanar with the elastic wire arm. The elastic wire arm is in a vertical plane. In order to make the pin portion face outward and parallel to the central part, it is necessary to continue to fold outward to match and connect with the circuit contacts on the external fixed plate.

[0014] In combination with the first aspect, the present invention provides a third implementation of the first aspect, wherein the outer portion is an annular polygonal sheet with a constant width, and an inwardly recessed corner portion is provided at its corner, and the straight edge portion of the outer portion except the corner portion is folded in the same direction to form the elastic wire arm.

[0015] In combination with the third embodiment of the first aspect, the present invention provides a fourth embodiment of the first aspect, wherein a connector is provided between the corner portion and the elastic wire arm, and the connector has at least two bending lines.

[0016] In combination with the third embodiment of the first aspect, the present invention provides a fifth embodiment of the first aspect, wherein the central portion has a pin hole for installing a ball pin, and the central portion is movably connected to the external fixed structure through the ball pin.

[0017] It is worth mentioning that the existing sensor anti-shake modules all directly suspend the sensor through the spring clip, and only provide support and limit through the spring clip. However, in order to reduce the space occupied and achieve a larger elastic adjustment range, the spring clip structure will be adjusted to have a thinner thickness and a longer connecting arm. This change leads to a reduction in the support effect obtained by the sensor. In order to improve stability, a ball pin or ball seat will be provided on the base of the entire camera module, and a ball seat or ball pin will be provided on the structure for carrying the sensor, and a movable connection is achieved through the cooperation of the ball seat and the ball pin. It can not only provide a supporting effect, but also limit its range of motion and trajectory while ensuring that it has a certain degree of freedom.

[0018] In combination with the first aspect and the first to fifth embodiments thereof, the present invention provides a sixth embodiment of the first aspect, wherein a plurality of through grooves are engraved on the spring sheet body, and an inner groove communicating with the corresponding through grooves is provided at the center, and an outer groove communicating with the corresponding through grooves is provided at the periphery;

[0019] After a layer of insulating material is covered on the surface of the spring body, a conductive material is filled in the through groove, and the conductive material is accumulated in the inner groove to form an inner pin, and in the outer groove to form an outer pin.

[0020] It should be noted that due to the small size of the shrapnel in the micro sensor, it can generally only be made of technical materials such as memory alloys. However, since the sensor is fixed at the center of the shrapnel, the existing voice coil motor conducts electricity through the shrapnel. The solution cannot be applied to this solution. In the existing sensor anti-shake module, a separate FPC is set for connection. This method will inevitably require the center of the shrapnel to be hollowed out, affecting its structural strength and support effect. At the same time, the separately set FPC has a certain length, and the FPC soft belt that cannot be fixed and constrained will affect the motion control of the sensor.

[0021] In this embodiment, an integrated spring sheet main body structure design is directly adopted, by directly opening multiple grooves on the surface of the spring sheet main body, and by filling a layer of insulation to achieve shielding, and by conducting materials in each groove to achieve the independence of the circuit, or directly etching the conductive circuit on the entire metal plate, the independence of the circuit can also be achieved. This method not only ensures the integrity of the spring sheet, avoids the need to set up a separate FPC, and saves space; at the same time, it can form an independent and stable circuit to ensure the normal connection between the sensor and the external circuit.

[0022] In combination with the first aspect and its first to fifth embodiments, the present invention provides a seventh embodiment of the first aspect, wherein the spring body is formed by a multi-layer functional layer patch, and the functional layer includes a spring layer and a circuit layer that are insulated from each other.

[0023] In combination with the seventh embodiment of the first aspect, the present invention provides an eighth embodiment of the first aspect, wherein the circuit layer is a soft FPC structure, and an inner pin for connecting the sensor is formed in the center, and an outer pin for connecting the external circuit is formed in the periphery.

[0024] In combination with the seventh implementation of the first aspect, the present invention provides a ninth implementation of the first aspect, wherein the functional layer further includes an insulating layer arranged between the circuit layer and the spring layer.

[0025] The beneficial effects of the present invention are:

[0026] Under the condition that the elastic K value in the X / Y direction is appropriate, the elastic K value in the Z direction can be greatly improved, and the posture difference in Sensor-Shift and the displacement in the Z direction can be greatly reduced; through the multi-layer bonding method, the spring sheet originally used as the sensor carrier can also be used as a circuit structure connecting the sensor and the external circuit without affecting the original elastic performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a first axial side schematic diagram of the entire FPC multi-layer spring sheet in the present invention in an unbent state;

[0028] Figure 2 It is a top view of the entire FPC multi-layer spring sheet in the present invention in an unbent state;

[0029] Figure 3 It is a second axial side schematic diagram of the entire FPC multi-layer spring sheet in the present invention in an unbent state;

[0030] Figure 4 It is an exploded view of the entire FPC multi-layer spring sheet in the present invention after the multi-layer structure is split in an unbent state;

[0031] Figure 5 It is a first axial schematic diagram of the entire FPC multi-layer spring sheet after being bent and formed in the present invention;

[0032] Figure 6 It is a top view of the entire FPC multi-layer spring sheet after being bent and formed in the present invention;

[0033] Figure 7 It is a schematic diagram of the second axis side of the entire FPC multi-layer spring sheet after being bent and formed in the present invention;

[0034] Figure 8 It is a side view of the entire FPC multi-layer spring sheet after being bent and formed in the present invention.

[0035] In the figure: 1-center part, 2-elastic wire arm, 3-corner part, 4-inner pin, 5-outer pin, 6-circuit layer, 7-insulating layer, 8-spring layer, 9-pin part, 10-pin hole. DETAILED DESCRIPTION

[0036] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments.

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0039] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0040] In the description of this application, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the application is usually placed when in use. It is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, if the terms "first", "second", etc. appear in the description of this application, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0041] In addition, if the terms "horizontal" or "vertical" appear in the description of this application, it does not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0042] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] Embodiment 1:

[0044] Existing miniature cameras are often used in mobile terminal devices such as mobile phones, and are characterized by their small size. Since the optical image stabilization function needs to be achieved within a certain volume, an electric control mechanism consisting of an electromagnetic structure and an elastic body is usually used to compensate for the motion of the lens module or sensor. This structure can achieve accurate electric control under the premise of a sufficiently small volume, in which the spring as a limit structure is the core functional component.

[0045] The present embodiment discloses a novel bent FPC spring sheet structure, which is arranged in a miniature camera with a sensor anti-shake function, and includes an elastic and conductive spring sheet body, the elastic body includes an outer portion and a central portion 1 for supporting the sensor, the central portion 1 has at least two connecting portions extending outward and connected to the outer portion, the outer portion has a plurality of elastic wire arms 2 that are flipped to one side to form an elastic wire arm that is not parallel to the plane where the central portion 1 is located, and the elastic wire arm 2 is connected to an external fixed structure.

[0046] An electromagnetic structure connected to the sensor is also provided in the camera module, which can be fed with a directional current to make it move regularly. The electromagnetic structure controls the sensor to move relative to the lens module, thereby achieving the effect of motion compensation. The movement mode in the prior art is only to translate or fold along the X / Y axis in the direction of the plane where the sensor is located, and the Z axis (i.e., perpendicular to the sensor plane direction) direction is not required, which results in the spring sheet structure being unable to provide a good elastic constraint effect when the entire sensor moves in the Z axis direction. In order to improve the elastic constraint force in the Z axis direction, the spring sheet in the present invention is first cut on a whole sheet structure to form a spring sheet shape, and then the excess material is removed and folded once or multiple times, so that the peripheral part surrounding the outside of the central part 1 forms multiple elastic wire arms 2. The peripheral part and the central part 1 are both sheet structures, and the angle mentioned in the above content is the angle between the planes where the larger surfaces of the two parts are located. After the peripheral part is folded, it forms a certain elastic area in the Z axis direction, and provides the sensor with stable elastic restrictions in multiple directions by cooperating with the central part 1.

[0047] Furthermore, the angle between the elastic wire arm 2 and the plane where the central portion 1 is located is in the range of 60-90°, and is preferably 90°.

[0048] Furthermore, since the entire spring sheet is not only used to support the sensor but also integrated with the circuit, the central portion 1 has multiple contacts connected to the bottom of the sensor, and the entire spring sheet body is arranged with multiple independent circuits. At the same time, the peripheral portion has a pin portion 9 initially extending toward the central portion 1, and the pin portion 9 is folded outward for the first time with the elastic wire arm 2, and then folded for the second time to form a state facing the outside of the peripheral portion.

[0049] Since the pin portion 9 is an integral extension end of the entire spring sheet body, and the spring sheet body is formed by cutting a sheet, when the outer peripheral portion is folded to form the elastic wire arm 2, the pin portion 9 will also be folded and coplanar with the elastic wire arm 2. The elastic wire arm 2 is in a vertical plane, and in order to make the pin portion 9 face outward and parallel to the central portion 1, it needs to be further folded outward to match and connect with the circuit contacts on the external fixing plate.

[0050] Furthermore, the outer portion is a sheet body of an annular polygon and a constant width, and an inwardly concave corner portion 3 is provided at its corner, and the straight side portion of the outer portion except the corner portion 3 is folded in the same direction to form the elastic wire arm 2, and a connector is provided between the corner portion 3 and the elastic wire arm 2, and the connector has at least two bending lines. The so-called polygon refers to the structure of the annular metal sheet body having multiple corners and straight bodies formed by cutting, and because the width is kept constant, directly folding the straight body 90 degrees will damage the entire outer portion. The general method is to cut a groove at the corner, and then the groove depth is the width of the entire elastic wire arm 2. However, this method will also reduce the structural strength of the entire outer portion and form stress concentration at the cutting groove. In order to achieve a better folding effect, under the premise of not affecting the structural strength of the spring sheet, it is also necessary to weigh the process difficulty, and then directly form an inwardly concave corner portion 3 at the corner during cutting. The so-called inward depression means that the corner of a polygonal ring protrudes toward the center, and when the width remains unchanged, it can ensure that there will be no stress concentration point when the straight body on both sides is folded, or even defects such as cracks and wrinkles in the straight line. At the same time, the folding line of the straight body is on the inwardly depressed corner part 3, and the folding line is relatively uniform, and the structural stability is relatively high.

[0051] Embodiment 2:

[0052] This embodiment is optimized and limited based on the above embodiment 1. Figure 1-8 As shown, the entire spring sheet body has the structural appearance of the above-mentioned embodiment 1 after being manufactured and formed, including a central rectangular central portion 1 and an annular quadrilateral peripheral portion surrounding the outer side of the central portion 1.

[0053] There are two connecting parts between the peripheral part and the central part 1. In the initial stage of production, the central part 1, the connecting part and the peripheral part are all structures cut and formed on the same sheet, so they are on the same plane and are connected in an integrated manner. Corner parts 3 are provided at the four corners of the peripheral part, and the straight part of the peripheral part has a pin part 9 extending inward. The straight part of the peripheral part is folded for the first time to form an elastic wire arm 2 vertically arranged upward and a pin part 9 downward, and then the pin part 9 is turned outward by the second folding, so that the outer pin 5 on its surface is buckled downward, thereby fitting with the electric contact on the base of the external camera module.

[0054] That is to say, the central part 1 is used to connect the sensor, and the pin part 9 of the peripheral part is used to be fixed on the external structure. Under the premise of satisfying conductivity, the sensor can be suspended relative to the external structure. At this time, it can be seen that since the upper part of the pin part 9 is the elastic wire arm 2, but the elastic wire arm 2 and the pin part 9 are not in the same horizontal plane, the forces on different planes will be mainly provided with elastic restoring force by the planar structure perpendicular to the plane. The existing integrated planar spring structure can only provide a good elastic limiting effect in one direction, while the space spring in this embodiment is sufficient to support the sensor for displacement elastic limiting at multiple angles.

[0055] In this embodiment, the entire spring sheet body has a three-layer structure, which is a circuit layer 6, an insulating layer 7 and a spring sheet layer 8 in sequence.

[0056] The circuit layer 6 is a copper layer for routing. The center part 1 has an inner pin 4 on its surface, which is connected to the sensor contact point to connect the signal line of the middle sensor to the outside. The insulating layer 7 is a PI layer for insulation. The bottom shrapnel layer 8 is the main structure of the entire shrapnel, which can be made of rolled copper, VCM shrapnel material or other metal materials to adjust the spring K value. The three parts are connected by adhesive.

[0057] Furthermore, the central part 1 of this embodiment has a pin hole 10 for installing a ball pin, and the central part 1 is movably connected to the external fixed structure through the ball pin.

[0058] The present invention is not limited to the above optional implementations, and anyone can derive other various forms of products under the enlightenment of the present invention. The above specific implementations should not be understood as limiting the scope of protection of the present invention. The scope of protection of the present invention should be based on the definition in the claims, and the description can be used to interpret the claims.

Claims

1. A novel bent FPC spring structure is provided in a miniature camera with a sensor anti-shake function, characterized in that: The invention comprises an elastic and conductive spring sheet body, the spring sheet body comprising a peripheral portion (2) and a central portion (1) for supporting a sensor, the central portion (1) having at least two connecting portions (12) extending outward and connected to the peripheral portion (2), the peripheral portion (2) having a plurality of elastic wire arms (11) turned up to one side to form a non-parallel plane with the central portion (1), the elastic wire arms (11) being connected to an external fixing structure; The peripheral portion (2) has a pin portion (9) initially extending toward the central portion (1); after the pin portion (9) is partially folded outwardly with the elastic wire arm (11) for the first time, the elastic wire arm (11) is in a vertical plane; the pin portion (9) is folded for the second time to form a state parallel to the central portion (1) and facing the outside of the peripheral portion (2).

2. According to claim 1, a novel bent FPC spring structure is characterized in that: The angle between the elastic wire arm (11) and the plane where the central portion (1) is located is in the range of 60-90°.

3. According to the novel bent FPC spring structure of claim 1, it is characterized by: The peripheral portion (2) is a sheet body of an annular polygon with a constant width, and an inwardly recessed corner portion (3) is provided at its corner, and the straight edge portion of the peripheral portion (2) except the corner portion (3) is folded in the same direction to form the elastic wire arm (11).

4. The novel bent FPC spring sheet structure according to claim 3 is characterized in that: A connecting body is provided between the corner portion (3) and the elastic wire arm (11), and the connecting body has at least two bending lines.

5. The novel bent FPC spring sheet structure according to claim 3 is characterized in that: The central part (1) has a pin hole (10) for installing a ball pin, and the central part (1) is movably connected to an external fixed structure via the ball pin.

6. A novel bent FPC spring sheet structure according to any one of claims 1 to 5, characterized in that: The spring sheet body is engraved with a plurality of through grooves, and an inner groove communicating with the corresponding through grooves is provided at the central portion (1), and an outer groove communicating with the corresponding through grooves is provided at the peripheral portion (2); After a layer of insulating material is coated on the surface of the spring body, a conductive material is filled in the through groove, and the conductive material is deposited in the inner groove to form an inner pin (4), and in the outer groove to form an outer pin (5).

7. A novel bent FPC spring sheet structure according to any one of claims 1 to 5, characterized in that: The spring sheet body is formed by a multi-layer functional layer patch, and the functional layer comprises a spring sheet layer (8) and a circuit layer (6) which are insulated from each other.

8. The novel bent FPC spring sheet structure according to claim 7 is characterized in that: The circuit layer (6) is a soft FPC structure, and has an inner pin (4) for connecting to a sensor formed in the central portion (1), and an outer pin (5) for connecting to an external circuit formed in the peripheral portion (2).

9. The novel bent FPC spring structure according to claim 7 is characterized in that: The functional layer further comprises an insulating layer (7) arranged between the circuit layer (6) and the spring layer (8).

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