CN222394207U - Back burnt adjusting module - Google Patents

Abstract

The utility model discloses a back focus adjusting module, which comprises a fixed base, a movable bracket and a driving assembly, wherein the movable bracket is provided with a mounting bracket for mounting a lens or an image sensor, the movable bracket is in sliding connection with the fixed base, the driving assembly is arranged on the fixed base and is connected with the movable end of the driving assembly, the driving assembly comprises a driving motor, a gear reduction box and a helical gear rack transmission mechanism, the rotating shaft end of the driving motor is connected with the input end of the gear reduction box, the output end of the gear reduction box is connected with the input end of the helical gear rack transmission mechanism, and the output end of the helical gear rack transmission mechanism is connected with the movable bracket. Adopt helical gear rack drive mechanism, turn into rectilinear motion with the rotary motion of gear reduction box output through helical gear rack drive mechanism to the burnt regulation after the movable support carries out is driven accurately, improved the transmission precision and the life of adjusting the module, help improving imaging quality, still avoided the production of great noise.

Description

Back burnt adjusting module

Technical Field

The utility model relates to the field of focusing module structures, in particular to a back focus adjusting module.

Background

ABF (Auto Back Focus) focusing module, namely automatic back focus adjusting module, for automatically adjusting back focus of lens to ensure that image is always clear. The working principle is that the back focal length of the optical system is changed by driving the lens or the image sensor to move back and forth through the driving component.

The problem that the driving assembly of the traditional ABF focusing module is large in noise and low in bearing capacity is solved, so that the whole module can generate large mechanical vibration in the adjusting process, the lens support is easy to shake, the stability is poor, and the imaging quality is greatly affected.

Disclosure of utility model

The utility model aims to provide a back focus adjusting module to solve one or more technical problems in the prior art.

To achieve the purpose, the utility model adopts the following technical scheme:

A back focus adjusting module comprises a fixed base, a movable support and a driving assembly, wherein a mounting bracket for mounting a lens or an image sensor is arranged on the movable support, the movable support is in sliding connection with the fixed base, the driving assembly is arranged on the fixed base, the movable support is connected with a movable end of the driving assembly, the driving assembly comprises a driving motor, a gear reduction box and a bevel gear rack transmission mechanism, a rotating shaft end of the driving motor is connected with an input end of the gear reduction box, an output end of the gear reduction box is connected with an input end of the bevel gear rack transmission mechanism, and an output end of the bevel gear rack transmission mechanism is connected with the movable support.

Preferably, the helical gear and rack transmission mechanism comprises a transmission shaft, a helical gear and a helical rack, one end of the transmission shaft is connected with the output end of the gear reduction box, the helical gear is sleeved on the outer side of the transmission shaft, the helical rack is arranged on one side of the movable support, and the helical gear is meshed with the helical rack.

Preferably, the tooth width of the helical gear is larger than the tooth width of the helical rack.

Preferably, the helical gear and rack transmission mechanism further comprises a clamping ring, a limiting groove is formed in the other end of the transmission shaft, the clamping ring is arranged in the limiting groove, and the clamping ring is attached to the end portion of the helical gear.

Preferably, the fixed base is provided with a motor mounting plate parallel to the moving direction of the movable support, the gear reduction box is fixed on one side of the motor mounting plate, the transmission shaft extends to the other side of the motor mounting plate, and the driving motor is fixed on one side of the gear reduction box.

Preferably, the driving assembly further comprises a front limit inductor and a rear limit inductor, the front limit inductor and the rear limit inductor are arranged on the fixing base in a front-rear mode, one side of the movable support is provided with an induction piece, and the induction piece corresponds to the front limit inductor and the induction end of the rear limit inductor in a front-rear mode.

Preferably, the device further comprises a guide post and a linear bearing, wherein an installation seat is arranged at the bottom of the movable bracket, the linear bearing is embedded in the installation seat, the guide post is arranged in the fixed base, the guide post is positioned at two sides of the helical gear and rack transmission mechanism, and the inner side of the linear bearing is in sliding fit with the guide post.

Preferably, the device further comprises a compression spring, wherein the compression spring is sleeved on the outer side of the guide post, and two ends of the compression spring are respectively abutted to the top of the fixed base and the end face of the linear bearing.

Compared with the prior art, the utility model has the beneficial effects that the helical gear and rack transmission mechanism is adopted, and the rotary motion output by the gear reduction box is converted into linear motion through the helical gear and rack transmission mechanism, so that the movable support is accurately driven to carry out back focus adjustment, the transmission precision and the service life of the adjusting module are improved, the imaging quality is improved, and the generation of larger noise is avoided.

Drawings

The present utility model is further illustrated by the accompanying drawings, which are not to be construed as limiting the utility model in any way.

FIG. 1 is a schematic overall construction of one embodiment of the present utility model;

FIG. 2 is a schematic view of the structure of a helical gear-rack transmission mechanism according to one embodiment of the present utility model;

FIG. 3 is an enlarged partial schematic view of FIG. 2;

fig. 4 is a schematic view of the internal structure of one embodiment of the present utility model.

Wherein, the device comprises a fixed base 1, a movable bracket 2, a mounting bracket 21, a driving motor 3, a gear reduction box 4, a helical gear and rack transmission mechanism 5, a transmission shaft 51, a helical gear 52, a helical rack 53, a clamping ring 54, a limit groove 511, a motor mounting plate 11, a front limit sensor 55, a rear limit sensor 56, a sensing piece 57, a mounting seat 22, a guide post 61, a linear bearing 62 and a compression spring 63.

Detailed Description

The technical scheme of the utility model is further described below by the specific embodiments with reference to the accompanying drawings.

A back focus adjusting module of the embodiment comprises a fixed base 1, a movable support 2 and a driving component, wherein a mounting bracket 21 for mounting a lens or an image sensor is arranged on the movable support 2, the movable support 2 is slidably connected with the fixed base, the driving component is arranged on the fixed base 1, the movable support 2 is connected with a movable end of the driving component, the driving component comprises a driving motor 3, a gear reduction box 4 and a helical gear rack transmission mechanism 5, a rotating shaft end of the driving motor 3 is connected with an input end of the gear reduction box 4, an output end of the gear reduction box 4 is connected with an input end of the helical gear rack transmission mechanism 5, and an output end of the helical gear rack transmission mechanism 5 is connected with the movable support 2.

The helical gear and rack transmission mechanism 5 is adopted in the embodiment, and the helical gear and rack transmission mechanism 5 is used for converting the rotary motion output by the gear reduction box 4 into linear motion, so that the movable support 2 is accurately driven to carry out back focus adjustment, the transmission precision and the service life of the adjusting module are improved, the imaging quality is improved, and the generation of large noise is avoided. The gear reduction box 4 also plays a role in increasing torque, and further improves the stability of driving the movable support 2.

Preferably, the helical gear and rack transmission mechanism 5 comprises a transmission shaft 5, a helical gear 52 and a helical rack 53, one end of the transmission shaft 5 is connected with the output end of the gear reduction box 4, the helical gear 52 is sleeved on the outer side of the transmission shaft 5, the helical rack 53 is arranged on one side of the movable support 2, and the helical gear 52 is meshed with the helical rack 53. Bevel gear 52 with oblique tooth surface and bevel rack 53 are meshed, so that the transmission is stable, the impact and vibration are small, compared with other focusing mechanisms, the meshing of bevel gear 52 is tight, return difference (namely, gaps in forward and backward rotation) is reduced, the accuracy and consistency of focusing process of a focusing module are ensured, and the structure is simple. And the contact line of the tooth surfaces of the bevel gear 52 and the bevel rack 53 is long, the contact area is large, the bearing capacity is high, and the driving stability of the movable bracket 2 is further improved.

Further, the helical gear 52 has a larger tooth width than the helical rack 53. By arranging the helical gear 53 with a tooth width larger than that of the helical gear 53, the contact area between the tooth surface of the helical gear 52 and the tooth surface of the helical gear 53 is increased, the stability of transmission is improved, and transmission errors or vibration caused by poor contact of the tooth surface are avoided. The helical gear 52 with larger tooth width can better disperse load in the transmission process, and reduce the pressure on a unit area, thereby reducing the risks of abrasion and fatigue damage of tooth surfaces, and prolonging the service lives of the helical gear 52 and the helical rack 53.

Preferably, referring to fig. 3, the helical gear and rack transmission mechanism 5 further includes a collar 54, the other end of the transmission shaft 5 is provided with a limiting groove 511, the collar 54 is disposed in the limiting groove 511, and the collar 54 is attached to the end of the helical gear 52. Through set up spacing groove 511 at the other end of transmission shaft 5 to fix the rand 54 in spacing groove 511, make rand 54 and helical gear 52's tip laminating, can prevent effectively that helical gear 52 from taking place axial displacement in the transmission process from this, ensured helical gear 52 and helical rack 53 keep the exact meshing, avoided helical gear 52 to take place the drive inefficacy that the displacement leads to.

Preferably, the fixed base is provided with a motor mounting plate 11 parallel to the moving direction of the movable support 2, the gear reduction box 4 is fixed on one side of the motor mounting plate 11, the transmission shaft 5 extends to the other side of the motor mounting plate 11, and the driving motor 3 is fixed on one side of the gear reduction box 4.

Through set up motor mounting panel 11 on unable adjustment base to fix the gear reduction box 4 in one side of motor mounting panel 11, make drive assembly's overall arrangement compacter and reasonable, effectively utilized the space, reduced the whole volume of module. By arranging the motor mounting plate 11 parallel to the moving direction of the movable bracket 2, the transmission shaft 5 can directly extend to the other side of the motor mounting plate 11 to be connected with the bevel gear 52, so that the bevel gear 52 is effectively meshed with the bevel gear 53.

Preferably, referring to fig. 4, the driving assembly further includes a front limit sensor 55 and a rear limit sensor 56, the front limit sensor 55 and the rear limit sensor 56 are disposed on the fixed base 1, one side of the movable bracket 2 is provided with a sensing piece 57, and the sensing piece 57 corresponds to the sensing ends of the front limit sensor and the rear limit sensor. The front limit sensor 55 and the rear limit sensor 56 are fixedly arranged front and back and are used for controlling the stroke range of the movable support 2, when the movable support 2 moves to a preset front limit position or rear limit position, the corresponding sensors are triggered, so that the movable support 2 stops moving continuously in the direction, direct collision between the movable support 2 and the fixed base 1 is avoided, and the service life of the adjusting module is prolonged.

Preferably, the movable bracket further comprises a guide post 61 and a linear bearing 62, the bottom of the movable bracket 2 is provided with a mounting seat 22, the linear bearing 62 is embedded in the mounting seat 22, the guide post 61 is arranged in the fixed base 1, the guide post 61 is positioned on two sides of the helical gear and rack transmission mechanism 5, and the inner side of the linear bearing 62 is in sliding fit with the guide post 61. Thus, by providing the guide post 61 and the linear bearing 62, the sliding fit of the movable bracket 2 and the fixed base 1 is achieved.

Further, the device also comprises a compression spring 63, wherein the compression spring 63 is sleeved on the outer side of the guide post 61, and two ends of the compression spring 63 respectively abut against the top of the fixed base 1 and the end face of the linear bearing 62. By providing the pressing spring 63 between the top of the fixed base 1 and the linear bearing 62, the meshing gap between the helical gear 52 and the helical rack 53 is further reduced by the pressure provided by the compression state of the pressing spring 63 and acting on the end face of the linear bearing 62, and the transmission accuracy is improved.

The technical principle of the present utility model is described above in connection with the specific embodiments. The description is made for the purpose of illustrating the general principles of the utility model and should not be taken in any way as limiting the scope of the utility model. Other embodiments of the utility model will be apparent to those skilled in the art from consideration of this specification without undue burden.

Claims (8)

1. A back focus adjustment module, characterized in that it comprises a fixed base, a movable bracket and a driving assembly, the movable bracket is provided with a mounting bracket for mounting a lens or an image sensor, the movable bracket is slidably connected to the fixed base, the driving assembly is arranged on the fixed base, and the movable bracket is connected to the movable end of the driving assembly; the driving assembly comprises a driving motor, a gear reduction box, and a helical rack and pinion transmission mechanism, the rotating shaft end of the driving motor is connected to the input end of the gear reduction box, the output end of the gear reduction box is connected to the input end of the helical rack and pinion transmission mechanism, and the output end of the helical rack and pinion transmission mechanism is connected to the movable bracket. 2. A back focus adjustment module according to claim 1, characterized in that the helical gear rack transmission mechanism includes a transmission shaft, a helical gear and a helical rack, one end of the transmission shaft is connected to the output end of the gear reduction box, the helical gear is sleeved on the outside of the transmission shaft, the helical rack is arranged on one side of the movable bracket, and the helical gear is meshed with the helical rack. 3. A back focus adjustment module according to claim 2, characterized in that the tooth width of the helical gear is greater than the tooth width of the helical rack. 4. A back focus adjustment module according to claim 2, characterized in that the helical gear rack transmission mechanism also includes a clamping ring, a limiting groove is opened at the other end of the transmission shaft, the clamping ring is arranged in the limiting groove, and the clamping ring is in contact with the end of the helical gear. 5. A back focus adjustment module according to claim 2, characterized in that a motor mounting plate parallel to the movable direction of the movable bracket is provided on the fixed base, the gear reduction box is fixed on one side of the motor mounting plate, the transmission shaft extends to the other side of the motor mounting plate, and the drive motor is fixed on one side of the gear reduction box. 6. A rear focus adjustment module according to claim 1, characterized in that the driving component also includes a front limit sensor and a rear limit sensor, the front limit sensor and the rear limit sensor are arranged front and back on the fixed base, and a sensor sheet is provided on one side of the movable bracket, and the sensor sheet corresponds front and back to the sensing ends of the front limit sensor and the rear limit sensor. 7. A back focus adjustment module according to claim 1, characterized in that it also includes a guide column and a linear bearing, a mounting seat is provided at the bottom of the movable bracket, the linear bearing is embedded in the mounting seat, the guide column is arranged in the fixed base, the guide column is located on both sides of the bevel gear rack transmission mechanism, and the inner side of the linear bearing is slidably matched with the guide column. 8. A back focus adjustment module according to claim 7, characterized in that it also includes a compression spring, wherein the compression spring is sleeved on the outside of the guide column, and the two ends of the compression spring are respectively against the top of the fixed base and the end surface of the linear bearing.