CN113296224A

CN113296224A - Step motor type camera module

Info

Publication number: CN113296224A
Application number: CN202010103490.3A
Authority: CN
Inventors: 许勇; 杨伟成; 杜智勇
Original assignee: Geke Microelectronics Shanghai Co Ltd
Current assignee: Geke Microelectronics Shanghai Co Ltd; Galaxycore Shanghai Ltd Corp
Priority date: 2020-02-20
Filing date: 2020-02-20
Publication date: 2021-08-24

Abstract

The invention provides a stepping motor type camera module, which comprises: the device comprises a stepping motor assembly, a lens module and a transmission assembly; the stepping motor assembly is positioned at least one corner of the lens module and comprises stator assemblies arranged at two sides of the corner and a rotor assembly positioned between the stator assemblies; the rotor assembly comprises permanent magnets arranged at two ends and respectively corresponds to the stator assemblies at two sides of the corner; the transmission assembly is arranged between the rotor assembly and the lens module; the stator assembly comprises a coil loop, and the coil loop is suitable for generating a changing magnetic field to push the rotor assembly to rotate so as to push the lens module to move through the transmission assembly in a matching action manner. The invention provides a novel large-stroke camera module.

Description

Step motor type camera module

Technical Field

The invention relates to the technical field of camera modules, in particular to a stepping motor type camera module.

Background

With the rapid development of the smart phone industry, the requirements of people on the imaging effect of a mobile phone Camera are gradually increased, and compared with the traditional Camera system, a mobile phone Camera Module (CCM) is widely applied to various new-generation portable Camera devices due to the advantages of miniaturization, low power consumption, low cost, high image quality and the like.

At present, the structure of the camera module includes a lens unit, a Voice Coil Motor (VCM), an infrared cut-off filter, an image sensor, a Flexible Printed Circuit Board (FPC) or a Printed Circuit Board (PCB), and a connector connected to a main Board of the mobile phone.

Among them, the voice coil motor is used to realize an auto-focusing function of the lens unit, and the voice coil motor generally includes a magnet, a coil, and the like as an actuator for driving the lens unit. In the working process of the camera module, current is firstly supplied to the coil, a magnetic field is generated after the coil is supplied with the current, the magnetic field generated in the coil and the magnetic field generated by the magnet interact to generate electromagnetic force, and the coil or the magnet moves under the action of the electromagnetic force, so that the lens unit connected with the voice coil motor is driven to move, the image distance and the object distance of the camera module are adjusted, and clear images are presented.

Usually, a Hall Sensor (Hall-effect Sensor) may be further disposed in the voice coil motor, and the Hall Sensor is utilized to measure the change of the magnetic field in the voice coil motor, and the position of the coil or the magnet is determined according to the change of the magnetic field, thereby implementing the closed-loop control of the voice coil motor.

However, in the conventional art, in the camera module capable of realizing the closed-loop control of the voice coil motor, since the driving force of the voice coil motor is relatively small, and the lens module cannot use the latch state when standing still, the lens module is not easy to realize a large moving stroke.

Disclosure of Invention

The invention aims to provide a stepping motor type camera module, which solves the technical problem that the camera module of a voice coil motor in the prior art is difficult to realize a larger moving stroke.

In order to solve the above technical problem, the present invention provides a stepping motor type camera module, including:

the device comprises a stepping motor assembly, a lens module and a transmission assembly;

the stepping motor assembly is positioned at least one corner of the lens module and comprises stator assemblies arranged at two sides of the corner and a rotor assembly positioned between the stator assemblies;

the rotor assembly comprises permanent magnets arranged at two ends and respectively corresponds to the stator assemblies at two sides of the corner;

the transmission assembly is arranged between the rotor assembly and the lens module;

the stator assembly comprises a coil loop, and the coil loop is suitable for generating a changing magnetic field to push the rotor assembly to rotate so as to push the lens module to move through the transmission assembly in a matching action manner.

Preferably, the stator assembly is structured to match the shape and orientation of the mover assembly, such that the magnetic field generated by the coil loop is adapted to urge the permanent magnet to move, thereby cooperatively urging the lens module to move.

Preferably, the stator assembly further includes an iron core frame, short sides of the iron core frame are suitable for setting the coil loops, and an included angle between a direction of the long side of the iron core frame and a direction of the rotating shaft of the mover assembly is less than or equal to 80 °.

Preferably, an included angle between a direction of a long side of the core frame and a direction of a rotation shaft of the mover assembly is 45 °.

Preferably, the mover assembly further includes: and the screw rod is positioned between the two permanent magnets and is fixedly connected with the permanent magnets.

Preferably, the magnetic lines of force between the two permanent magnets intersect at 90 degrees.

Preferably, a hall element is included, which is adapted to detect motor movement for feedback to the control circuit unit, thereby adjusting the operating state of the stepper motor assembly.

Preferably, the transmission assembly comprises a turbine unit;

the turbine unit comprises an inner ring side and an outer ring side, and the outer ring side is provided with teeth matched with the thread part of the screw rod;

the inner ring side of the turbine unit is suitable for fixedly arranging the lens module;

the permanent magnet of the stepping motor unit drives the screw to rotate, so that the screw drives the turbine unit to move up and down, and the lens module is driven to move up and down.

Preferably, the coil loops of the stator assembly are adapted to pass an alternating current, such that each time the current is switched, its corresponding permanent magnet steps in a fixed direction.

Preferably, the coil loops of the stator assembly are adapted to drive the respective corresponding permanent magnets in a staggered manner so that the mover assembly continuously rotates.

Preferably, the number of the stepping motor assemblies is one to two.

Preferably, the centers of the two permanent magnets are provided with through holes, and two ends of the screw rod are suitable for being connected with the permanent magnets through the through holes.

Preferably, the turbine unit is further provided with a lens mounting ring and a stopping member, the lens mounting ring is suitable for mounting the lens module in an inner ring of the turbine unit, and the stopping member is suitable for fixing the turbine unit and preventing the turbine unit from moving up and down, so that the lens mounting ring drives the lens unit to move up and down.

Preferably, the camera module further comprises a base unit, and the stepping motor unit is arranged at one corner of the base unit.

Preferably, the turbine unit is disposed at or offset from the middle of the base unit.

Compared with the prior art, the stepping motor type camera module has the following beneficial effects:

according to the invention, the stepping motor assembly is arranged in the camera module, so that the driving force for the lens module can be improved, a larger moving stroke can be realized, and in addition, a larger lens module can be borne.

Further, since the stepping motor can control the stop of the movement through electromagnetic induction, a separate locking structure is not needed to be arranged in the camera module.

Drawings

Fig. 1 to 5 are schematic structural views of a stepping motor type camera module according to an embodiment of the present invention.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather construed as limited to the embodiments set forth herein.

Next, the present invention is described in detail by using schematic diagrams, and when the embodiments of the present invention are described in detail, the schematic diagrams are only examples for convenience of description, and the scope of the present invention should not be limited herein.

In order to make the above objects, features and advantages of the present invention more comprehensible, a structure of a stepping motor type camera module according to the present invention is described in detail below with reference to the accompanying drawings.

Referring to fig. 1 in combination, in particular, in this embodiment, the stepping motor type camera module includes: a stepping motor assembly, a lens module 100, and a transmission assembly 400.

The stepping motor assembly is located at least one corner of the lens module 100, and includes stator assemblies 200 disposed at both sides of the corner and a mover assembly 240 located between the stator assemblies 200.

It should be noted that, in the present embodiment, the phrase "located at least one corner of the lens module 100" refers to a position of the lens module 100, which corresponds to a corner of the base unit 500 (fig. 4) where the lens module 100 is located. And the stepper motor assembly is also positioned along both sides of this "corner" of the base unit 500. In this embodiment, the step motor assembly is formed by combining two asynchronous unidirectional motors, wherein each asynchronous unidirectional motor comprises a stator assembly and a rotor assembly.

Referring to fig. 2 in combination, in the present embodiment, the mover assembly 240 includes

permanent magnets

241 and 242 disposed at both ends, and the

permanent magnets

241 and 242 respectively correspond to the stator assembly 200 at both sides of the corner.

In this embodiment, the mover assembly 240 further includes: and the screw rod 300 is positioned between the two permanent magnets and fixedly connected with the

permanent magnets

241 and 242. Specifically, in this embodiment, a through hole 20 is disposed in the center of the two permanent magnets, and both ends of the screw 300 are adapted to be connected to the permanent magnet 241 and the permanent magnet 242 through the through hole 20.

And, referring to fig. 2 in combination, the magnetic lines of force between the two permanent magnets intersect at 90 degrees. That is, the N-pole and S-pole of the permanent magnet 241 and the permanent magnet 242 are orthogonal to each other in the drawing. The

permanent magnets

241 and 242 may be alternately moved by sending pulse signals to the two stator assemblies 200, respectively, to thereby drive the screw 300 to rotate.

The stator assembly 200 includes a coil loop 210, and the coil loop 210 is adapted to receive a pulse signal, generate a varying magnetic field through a varying current, and push the mover assembly to rotate, so as to push the lens module to move through the transmission assembly in a cooperative action.

Specifically, the stator assembly 200 is configured to match the shape and the direction of the mover assembly 240, such that the magnetic field generated by the coil loop 210 is suitable for pushing the two permanent magnets (the permanent magnet 241 and the permanent magnet 242) to move, thereby cooperatively acting on the transmission assembly 400 to push the lens module 100 to move.

As shown in fig. 1 and 3, the stator assembly 200 includes a core frame 230, the core frame 230 is relatively long in a transverse direction and is disposed along a side of the base unit 500, and a short side of the core frame 230 is adapted to dispose the coil loop 210. The short side of the core frame 230 is adapted to coincide with the height direction of the base unit 500.

Specifically, in this embodiment, an included angle a between a direction of the long side of the core frame 230 and a direction of the rotation axis of the mover assembly 240 is less than or equal to 80 °.

Therefore, the driving force of the stepping motor can be improved as much as possible, the camera module is ensured to occupy smaller space, and the camera module can be designed to be more compact.

Preferably, an included angle a between a direction of the long side of the core frame 230 and a direction of the rotation axis of the mover assembly 240 is 45 °. The angle enables the stepping motor to occupy the minimum space of the camera module, so that the camera module can be designed to be very compact.

In this embodiment, the coil loops of the stator assembly 200 are adapted to pass an alternating current, so that each time the current is switched, the corresponding permanent magnet steps in a fixed direction.

In the present embodiment, the coil loops 210 of the stator assembly 200 are adapted to drive the corresponding permanent magnets (permanent magnets 241 and 242) at different times, so that the mover assembly 240 continuously rotates.

Specifically, in this embodiment, the transmission assembly 400 is disposed between the mover assembly 240 and the lens module 100.

In the present embodiment, the transmission assembly 400 is a turbine unit; referring to fig. 4 in conjunction with fig. 1, the turbine unit 400 includes an inner race side 420 and an outer race side 410, the outer race side 410 being provided with teeth 44 that mate with the threaded portion 330 of the screw 300; the inner race side 420 of the turbine unit is adapted to fixedly position the lens module 100;

the permanent magnets (the permanent magnet 241 and the permanent magnet 242) of the stepping motor unit drive the screw 300 to rotate, so that the thread part 330 of the screw 300 interacts with the teeth 44 of the turbine unit 400, thereby driving the turbine unit 400 to move up and down, and further driving the lens module 100 to move up and down.

In this embodiment, the turbine unit 400 is further provided with a lens mounting ring (not shown) adapted to mount the lens module 100 on the inner ring side 420 of the turbine unit 400, and a stopper (not shown) adapted to fix the turbine unit 400 and prevent the turbine unit 400 from moving up and down, so that the lens mounting ring moves the lens unit 100 up and down.

Preferably, the number of the stepping motor assemblies is one to two.

In the embodiment where the stepping motor assemblies are two, one of the stepping motor assemblies (the first stepping motor assembly) is installed as shown in fig. 1, and the other stepping motor assembly (the second stepping motor assembly) is located at the position and the arrangement manner of the first stepping motor assembly in an axisymmetric relationship with the diameter of the lens unit, that is, at the other opposite corner of the base unit 500.

Referring to fig. 4, in this embodiment, the camera module further includes a base unit 500, and the stepping motor unit is disposed at one corner of the base unit.

In the present embodiment, the turbine unit is disposed at the middle of the base unit 500 or offset from the middle of the base unit 500.

In this embodiment, the stepping motor type camera module further includes a hall element (not shown), and the hall element is adapted to detect a motor movement to feed back to the control circuit unit, so as to adjust the working state of the stepping motor assembly.

Referring to fig. 5, in this embodiment, the stepping motor type camera module further includes a waterproof and dustproof film 700, and the waterproof and dustproof film 700 is located between the lens unit and the top end of the base unit 500 to prevent moisture and dust from entering the camera module and affecting the resolution of the lens.

Compared with the prior art that the voice coil motor is used as the driving part of the lens module, the stepping motor type camera module provided by the invention has the advantages that the driving force for the lens module is greatly improved, the larger moving stroke can be realized, and in addition, the larger lens module can be borne.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make variations and modifications of the present invention without departing from the spirit and scope of the present invention by using the methods and technical contents disclosed above.

Claims

1. The utility model provides a step motor formula camera module which characterized in that, camera module includes:

2. The stepping motor type camera module according to claim 1, wherein the stator assembly is configured to match the shape and direction of the mover assembly, such that the magnetic field generated by the coil loop is adapted to push the permanent magnet to move, thereby cooperatively pushing the lens module to move.

3. The stepping motor type camera module according to claim 1 or 2, wherein the stator assembly further comprises a core frame, the short side of the core frame is suitable for disposing the coil loop, and an included angle between a direction of the long side of the core frame and a direction of the rotation axis of the mover assembly is less than or equal to 80 °.

4. The stepping motor type camera module according to claim 3, wherein an angle between a direction of a long side of the core frame and a direction of a rotation axis of the mover assembly is 45 °.

5. The stepper-motor camera module of claim 1, wherein the mover assembly further comprises: and the screw rod is positioned between the two permanent magnets and is fixedly connected with the permanent magnets.

6. The stepping motor type camera module according to claim 5, wherein the magnetic lines of force between the two permanent magnets intersect at 90 degrees.

7. The stepper-motor camera module of claim 1, comprising a hall element adapted to detect motor movement for feedback to a control circuit unit to adjust the operating state of the stepper-motor assembly.

8. The stepper-motor camera module of claim 1, wherein the transmission assembly comprises a turbine unit;

9. The stepping motor type camera module according to claim 1, wherein the coil loop of the stator assembly is adapted to pass an alternating current so that the corresponding permanent magnet thereof steps in a fixed direction every time the current is switched.

10. The stepping motor type camera module according to claim 1 or 9, wherein the coil loops of the stator assembly are adapted to drive the respective corresponding permanent magnets at different times so that the mover assembly continuously rotates.

11. The stepper-motor camera module of claim 1, wherein the number of stepper motor assemblies is one to two.

12. The stepping motor type camera module according to claim 5, wherein a through hole is provided in the center of the two permanent magnets, and both ends of the screw are adapted to be connected to the permanent magnets through the through hole.

13. The stepping motor type camera module according to claim 8, wherein said turbine unit is further provided with a lens mounting ring adapted to mount said lens module in an inner race of said turbine unit, and a stopper member adapted to fix said turbine unit and prevent said turbine unit from moving up and down, so that said lens mounting ring moves said lens unit up and down.

14. The stepper-motor camera module of claim 1, further comprising a base unit, wherein the stepper-motor unit is disposed at a corner of the base unit.

15. The stepper-motor camera module of claim 14, wherein the turbine unit is disposed at or offset from the middle of the base unit.