CN220137469U - Lens barrel module and electronic device - Google Patents

Abstract

The utility model provides a lens barrel module and an electronic device, which are not easy to damage even if impact is applied to a rotary drum. The lens barrel module (2) has: a fixed cylinder (30) in which a cam groove (33) is formed on the inner peripheral surface, the cam groove including a spiral groove (33A) extending in a spiral shape and a tip groove (33C) extending in the circumferential direction at the tip of the spiral groove; a rotary drum (40) disposed radially inward of the fixed drum; and a drive unit (20) that includes a motor (21) that rotates the rotary drum. The rotary cylinder has a protruding portion (45) protruding radially outward and engaging with the cam groove of the fixed cylinder, and a driven gear (46) formed along the circumferential direction. A control unit (4) of the smart phone (1) rotates the motor in the opposite direction at a predetermined timing to move the protruding portion of the rotary drum from the front end groove of the cam groove of the fixed drum to the spiral groove.

Description

Lens barrel module and electronic device

Technical Field

The present utility model relates to a lens barrel module and an electronic device, and more particularly, to a lens barrel module capable of extending a lens barrel forward in an optical axis direction.

Background

A camera incorporated in a small electronic device such as a smart phone must be housed in a limited space, and therefore, there are often provided a mechanism for housing a lens barrel in a main body except for the time of photographing and for extending the lens barrel at the time of photographing (for example, refer to patent document 1). Such an extension mechanism includes: a rotary drum having pins protruding radially outward; and a fixed cylinder formed with a spiral cam groove for engagement of the pin, the pin of the rotating cylinder moving along the cam groove of the fixed cylinder when the rotating cylinder rotates relative to the fixed cylinder, whereby the rotating cylinder protrudes. The tip end portion of the cam groove formed in such a fixed cylinder is generally formed to extend in the circumferential direction to perform alignment in the axial direction of the rotary cylinder.

For example, it is considered that when an electronic apparatus falls down or the like in a state in which the rotary drum is extended at the time of photographing, an impact is applied to the rotary drum extended from the fixed drum, and a force pushing the rotary drum back into the inside of the fixed drum is applied. At this time, if the pin of the rotary cylinder is located at the front end portion extending in the circumferential direction of the cam groove of the fixed cylinder, there is no release place of the force pushing the rotary cylinder back into the inside of the fixed cylinder, and thus, an excessive force acts on the pin, which is separated from the cam groove of the fixed cylinder, or the pin is broken, so that the camera cannot be repaired. In addition, even if the pin of the rotary cylinder is not located at the front end portion of the cam groove of the fixed cylinder, the impact applied to the rotary cylinder is transmitted to the motor on the driving side or the like, and these components are broken.

Patent document 1: japanese patent No. 5328249 specification

Disclosure of Invention

The present utility model has been made in view of the above-described problems of the related art, and an object thereof is to provide a lens barrel module and an electronic apparatus which are not easily broken even when an impact is applied thereto.

A first aspect of the present utility model provides a lens barrel module, including: a fixed cylinder having a cam groove formed in an inner peripheral surface thereof, the cam groove including a spiral groove extending in a spiral shape and a tip groove extending in a circumferential direction from a tip of the spiral groove; a rotary cylinder disposed radially inward of the fixed cylinder, the rotary cylinder having at least one lens, a protruding portion protruding radially outward and engaged with the cam groove of the fixed cylinder, and a driven gear formed along a circumferential direction; and a drive unit that rotates the rotary drum, the drive unit including a motor, a drive gear that meshes with a driven gear of the rotary drum, and a rotation transmission mechanism that is capable of transmitting rotation of the motor to the drive gear, the rotation transmission mechanism including a torque limiter that is capable of cutting off transmission of rotation between the drive gear and the motor when a torque exceeding a predetermined torque is applied.

A lens barrel module according to a second aspect of the present utility model is the lens barrel module according to the first aspect, wherein the torque limiter includes: a first gear that rotates in association with rotation of the motor; a second gear that rotates in association with rotation of the drive gear; a washer disposed between the first gear and the second gear; and a biasing member that biases the washer toward one of the first gear and the second gear, and rotates integrally with the other of the first gear and the second gear.

A third aspect of the present utility model provides an electronic device, including: a lens barrel module including at least one lens; an image pickup element disposed on an optical axis of the at least one lens of the lens barrel module; and a control unit capable of controlling driving of the lens barrel module, the lens barrel module having: a fixed cylinder having a cam groove formed in an inner peripheral surface thereof, the cam groove including a spiral groove extending in a spiral shape and a tip groove extending in a circumferential direction from a tip of the spiral groove; a rotary cylinder disposed radially inward of the fixed cylinder, the rotary cylinder having a protruding portion protruding radially outward and engaging with the cam groove of the fixed cylinder, and a driven gear formed along a circumferential direction; and a drive unit that rotates the rotary cylinder, the drive unit having a motor, a drive gear that meshes with the driven gear of the rotary cylinder, and a rotation transmission mechanism that is capable of transmitting rotation of the motor to the drive gear, the control unit being configured to: when the protruding portion of the rotary cylinder of the lens barrel module is located in the front end groove of the cam groove of the fixed cylinder, the motor is rotated in the opposite direction at a predetermined timing to move the protruding portion of the rotary cylinder to the spiral groove of the cam groove of the fixed cylinder.

An electronic device according to a fourth aspect of the present utility model is the electronic device according to the third aspect, further comprising an acceleration sensor capable of detecting acceleration, wherein the control unit is configured to: the motor is rotated in the reverse direction in accordance with a detection signal from the acceleration sensor to move the protruding portion of the rotary cylinder of the lens barrel module toward the spiral groove of the cam groove of the fixed cylinder.

In the electronic device according to a fifth aspect of the present utility model, in the electronic device according to the third aspect, the rotation transmission mechanism of the lens barrel module includes a torque limiter capable of cutting off transmission of rotation between the motor and the drive gear when a torque exceeding a predetermined value is applied.

An electronic device according to a sixth aspect of the present utility model is the electronic device according to the fifth aspect, wherein the torque limiter of the lens barrel module includes: a first gear that rotates in association with rotation of the motor; a second gear that rotates in association with rotation of the drive gear; a washer disposed between the first gear and the second gear; and a biasing member that biases the washer toward one of the first gear and the second gear, and rotates integrally with the other of the first gear and the second gear.

Drawings

Fig. 1 is a perspective view illustrating a smart phone incorporating a lens barrel module in one embodiment of the present utility model.

Fig. 2 is a schematic diagram illustrating a functional structure of the smart phone shown in fig. 1.

Fig. 3 is a perspective view illustrating the lens barrel module shown in fig. 1.

Fig. 4 is an exploded perspective view of the lens barrel module shown in fig. 3.

Fig. 5 is a perspective view illustrating a fixed barrel in the lens barrel module shown in fig. 3.

Fig. 6 is an exploded perspective view of a driving unit in the lens barrel module shown in fig. 3.

Fig. 7 is a front view of the driving unit in a state in which the cover shown in fig. 6 is removed.

Fig. 8 is a left side view schematically illustrating the lens barrel module shown in fig. 1 in a contracted state.

Fig. 9 is a left side view schematically showing the lens barrel module shown in fig. 8 in an extended state.

Fig. 10 is a left side view schematically showing the lens barrel module shown in fig. 9 in a retracted state.

Description of the reference numerals

1: a smart phone; 2: a lens barrel module; 3: a camera; 4: a control unit; 5: an acceleration sensor; 6: an image pickup element; 10: a base plate; 11. 32: a photointerrupter; 20: a driving unit; 21: a motor; 24: a drive gear; 25: a rotation transmission mechanism; 30: a fixed cylinder; 31: a cylindrical portion; 33: cam grooves; 33A: a spiral groove; 33B: a rear end slot; 33C: a front end groove; 40: a rotary drum; 41: a cylindrical portion; 42: a lens; 45: a protruding portion; 46: a driven gear; 50: a direct-acting cylinder; 60: a cover ring; 62: dustproof drip-proof sheet; 250: a worm; 251: a double-stage gear; 252-254: a gear; 255: a coil spring; 256: and a gasket.

Detailed Description

Hereinafter, an embodiment of an electronic apparatus having a lens barrel module according to the present utility model will be described in detail with reference to fig. 1 to 10. In fig. 1 to 10, the same or corresponding components are denoted by the same reference numerals, and overlapping description thereof is omitted. In fig. 1 to 10, the scale and the dimensions of each component are exaggerated, and some components are omitted. In the following description, unless otherwise specified, terms such as "first" and "second" are used merely to distinguish components from each other, and do not denote a particular order or sequence.

Fig. 1 is a perspective view showing a smartphone 1 as an example of an electronic device of the present utility model, and a camera 3 including a lens barrel module 2 of the present utility model is incorporated in the smartphone 1. As shown in fig. 1, the smart phone 1 includes a control unit 4 for controlling electrical components in the smart phone 1, and an acceleration sensor 5 capable of detecting acceleration of the smart phone 1. The camera 3 and the acceleration sensor 5 are connected to the control unit 4, respectively. The electronic device of the present utility model is not limited to the smart phone described in the present embodiment, and the present utility model can be applied to various electronic devices such as a tablet pc, a laptop computer, and an unmanned aerial vehicle.

Fig. 2 is a schematic diagram showing a functional structure of the smartphone 1 shown in fig. 1. As shown in fig. 2, the smartphone 1 has: a camera 3 including a lens barrel module 2 and an image pickup element 6; an acceleration sensor 5 capable of detecting acceleration of the smartphone 1; a display 7 composed of a liquid crystal display, an organic EL display, or the like; a storage unit 8 including ROM, RAM, flash memory, and the like; a communication unit 9 for performing data communication by connecting to a network; and a control unit 4 for controlling the operations of the respective constituent elements.

The storage unit 8 stores programs for controlling an OS (Operating System), the smartphone 1, programs for executing steps described below, other various data, and the like. The control section 4 has a processor (CPU), ROM, RAM, and the like, and realizes various functions by loading a program stored in the storage section 8 into the RAM and executing the program with the processor.

Fig. 3 is a perspective view showing the lens barrel module 2, and fig. 4 is an exploded perspective view. As shown in fig. 3 and 4, the lens barrel module 2 has: an annular base plate 10; a drive unit 20 having a motor 21; a fixing cylinder 30 fixed to the base plate 10 by screws (not shown); a rotary drum 40 disposed radially inward of the fixed drum 30; a linear cylinder 50 housed inside the rotary cylinder 40; a cover ring 60 attached to the front end portion of the cylindrical portion 31; and a dust-proof drip-proof sheet 62 sandwiched between the cover ring 60 and the cylindrical portion 31. In the present embodiment, the +z direction in fig. 3 is referred to as "front" or "front", and the-Z direction is referred to as "rear" or "rear", for convenience.

Fig. 5 is a perspective view showing the fixed cylinder 30. As shown in fig. 3 to 5, the fixed tube 30 is formed of, for example, resin or the like, and includes a cylindrical portion 31 and a photointerrupter 32 attached to the outer peripheral portion of the cylindrical portion 31. The photointerrupter 32 can transmit a detection signal to the control unit 4, and the photointerrupter 32 faces the inner space of the cylindrical portion 31 through the opening 38 formed in the cylindrical portion 31. A plurality of cam grooves 33 and axial grooves 34, 35 extending in the axial direction (Z direction) from the rear edge of the cylindrical portion 31 are formed in the inner peripheral surface of the cylindrical portion 31. Each cam groove 33 includes a spiral groove 33A extending in a spiral shape, a rear end groove 33B extending in the circumferential direction from the rear end of the spiral groove 33A, and a front end groove 33C extending in the circumferential direction from the front end of the spiral groove 33A. Further, the cylindrical portion 31 is formed with a notch 39 at a connection portion with the drive unit 20. In the present specification, "spirally extend" means extending so that the circumferential position changes in the axial direction.

As shown in fig. 4, the base plate 10 has a photointerrupter 11 attached to the outer peripheral portion and an insertion piece 12 inserted into an axial groove 35 of the inner peripheral surface of the cylindrical portion 31 of the fixed tube 30. The photointerrupter 11 of the base plate 10 is located on the-Z direction side of the photointerrupter 32 of the fixed cylinder 30, and the photointerrupter 11 faces the inner space of the cylindrical portion 31 through the opening 38 similarly to the photointerrupter 32. The photointerrupter 11 can transmit the detection signal to the control unit 4 in the same manner as the photointerrupter 32.

The rotary cylinder 40 is rotatable relative to the fixed cylinder 30 and is movable in the axial direction. As shown in fig. 4, the rotary drum 40 includes a cylindrical portion 41, at least 1 lens 42 accommodated in the cylindrical portion 41, a cover glass 43 disposed in front of the lens 42, and a ring member 44 attached to the front end portion of the cylindrical portion 41. As shown in fig. 1, the rotary drum 40 is disposed so as to be exposed from an opening 1B formed in the rear panel 1A of the smartphone 1. The image pickup device 6 of the camera 3 of the smartphone 1 is disposed on an image pickup surface on which the light transmitted through the lens 42 is imaged.

The rotary cylinder 40 includes a plurality of protruding portions 45 protruding radially outward from the rear end outer peripheral portion of the cylindrical portion 41, and a driven gear 46 formed circumferentially on the rear end outer peripheral portion of the cylindrical portion 41. The outer diameter of each protruding portion 45 is slightly smaller than the width of the cam groove 33 of the fixed cylinder 30 in the circumferential direction (hereinafter referred to as circumferential width), and each protruding portion 45 is engageable with the cam groove 33 of the fixed cylinder 30 and movable along the cam groove 33 inside the cam groove 33. By the engagement of the protruding portion 45 of the rotary cylinder 40 with the spiral groove 33A of the cam groove 33 of the fixed cylinder 30, when the rotary cylinder 40 rotates relative to the fixed cylinder 30, the rotary cylinder 40 moves in the Z direction relative to the fixed cylinder 30 along the shape of the cam groove 33 of the fixed cylinder 30.

The linear motion cylinder 50 includes a cylindrical portion 51, a plurality of protrusions 52 protruding radially outward from the cylindrical portion 51, a flange portion 53 extending radially outward from a rear end of the cylindrical portion 51, a plurality of engagement portions 54 extending radially outward from the flange portion 53, and a detection piece 55 similarly extending radially outward from the flange portion 53. Each of the protrusions 52 of the linear cylinder 50 engages with a groove (not shown) formed on the inner peripheral surface of the cylindrical portion 41 of the rotary cylinder 40 and extending in the circumferential direction. The circumferential width of each engagement portion 54 of the linear motion cylinder 50 is slightly smaller than the circumferential width of the axial groove 34 of the fixed cylinder 30, and each engagement portion 54 is engageable with the axial groove 34 of the fixed cylinder 30 and movable in the Z direction along the axial groove 34 inside the axial groove 34. With this configuration, the linear cylinder 50 is not rotated with respect to the fixed cylinder 30, and can move in the axial direction together with the rotary cylinder 40 while rotating with respect to the rotary cylinder 40.

The detection piece 55 of the linear motion tube 50 extends outward through the opening 38 of the fixed tube 30, and the photointerrupter 11 of the base plate 10 adjacent to the opening 38 and the photointerrupter 32 of the fixed tube 30 can detect the detection piece 55 of the linear motion tube 50.

Fig. 6 is an exploded perspective view of the driving unit 20. As shown in fig. 6, the drive unit 20 includes a motor 21 driven by the control unit 4, a gear housing 22 attached to the base plate 10, a gear cover 23 attached to the gear housing 22 by screws 91, a drive gear 24 engaged with a driven gear 46 of the rotary drum 40, and a rotation transmission mechanism 25 capable of transmitting rotation of the motor 21 to the drive gear 24.

Fig. 7 is a front view of the drive unit 20 with the gear cover 23 removed. As shown in fig. 6 and 7, the rotation transmission mechanism 25 includes: a worm 250 mounted to an output shaft of the motor 21; a two-stage gear 251 including a worm wheel 251A meshed with the worm 250 and a gear 251B disposed on the-Z direction side of the worm wheel 251A; a gear 252 (first gear) that meshes with a gear 251B of the dual stage gear 251; a gear 253 (second gear) coaxially arranged with the gear 252; a gear 254 that meshes with both the gear 253 and the drive gear 24; a coil spring 255 as a biasing member, which is housed in a central portion of the gear 252; and a washer 256 disposed between the coil spring 255 and the main body 253A of the gear 253.

The double stage gear 251 is attached to a gear shaft 221 extending in the +z direction from the gear housing 22, and is rotatable about the gear shaft 221. The gear 252 is attached to a gear shaft 222 extending in the +z direction from the gear housing 22, and is rotatable about the gear shaft 222. The shaft portion 253B of the gear 253 is also attached to the gear shaft 222, and the gear 253 can rotate around the gear shaft 222. The gear 254 is attached to a gear shaft 223 protruding in the +z direction from the gear housing 22, and is rotatable about the gear shaft 223. The drive gear 24 is attached to a gear shaft 224 extending in the +z direction from the gear housing 22, and is rotatable about the gear shaft 224.

The coil spring 255 of the rotation transmission mechanism 25 is housed in a compressed state in the center portion of the gear 252, and biases the washer 256 toward the main body 253A of the gear 253 with a predetermined force. One end of the coil spring 255 is engaged with a groove 252A formed in the center of the gear 252, and the coil spring 255 rotates together with the gear 252. The washer 256 biased by the coil spring 255 also rotates together with the gear 252, and when the gear 252 rotates, the gear 253 rotates together with the gear 252 by friction force generated between the washer 256 and the main body 253A of the gear 253. On the other hand, when a torque exceeding the friction force acts on the washer 256, the washer 256 and the main body 253A of the gear 253 slide to idle, and transmission of rotation between the gear 252 and the gear 253 is cut off. As described above, in the present embodiment, the gear 252, the coil spring 255, the washer 256, and the gear 253 function as a torque limiter that cuts off transmission of rotation between the gear 252 and the gear 253 when a predetermined torque is applied.

When the camera function of the smartphone 1 is turned off, as shown in fig. 3, the rotation tube 40 is housed inside the fixed tube 30 of the lens barrel module 2 in the radial direction, and the rotation tube 40 is housed inside the rear panel 1A of the smartphone 1. The state of the lens barrel module 2 at this time is referred to as a "collapsed state".

Fig. 8 is a left side view schematically showing the lens barrel module 2 at this time. As shown in fig. 8, in the contracted state, the protruding portion 45 of the rotary cylinder 40 is located in the rear end groove 33B of the cam groove 33 of the fixed cylinder 30. When the photointerrupter 11 attached to the base plate 10 detects the detection piece 55 of the linear motion tube 50, a detection signal is transmitted to the control unit 4, and the control unit 4 can detect that the rotary tube 40 is housed inside the fixed tube 30.

When the user provides an instruction to turn on the camera function to the control section 4 using an input unit such as a touch panel on the display 7 of the smartphone 1, the control section 4 transmits a control signal to the motor 21 of the drive unit 20 of the lens barrel module 2, causing the motor 21 to rotate. The rotation of the motor 21 is transmitted to the drive gear 24 by the rotation transmission mechanism 25, and the drive gear 24 is rotated. Since the driven gear 46 of the rotary drum 40 is engaged with the driving gear 24, the rotary drum 40 rotates with the rotation of the driving gear 24. When the rotary drum 40 rotates, as described above, the rotary drum 40 moves in the Z direction with respect to the fixed drum 30 along the shape of the cam groove 33 of the fixed drum 30 by the engagement of the protruding portion 45 of the rotary drum 40 with the cam groove 33 of the fixed drum 30, and finally, as shown in fig. 9, the protruding portion 45 of the rotary drum 40 moves to the front end groove 33C of the cam groove 33 of the fixed drum 30. In this way, the motor 21 of the lens barrel module 2 is driven by the control unit 4, and the rotary drum 40 is extended in the +z direction. When the photointerrupter 32 attached to the fixed cylinder 30 detects the detection piece 55 of the linear motion cylinder 50, a detection signal is sent to the control unit 4, and the control unit 4 detects that the rotary cylinder 40 is extended, and turns on the camera function. The state of the lens barrel module 2 at this time is referred to as an "extended state".

Hereinafter, the direction in which the motor 21 rotates when the rotary drum 40 is brought from the contracted state to the extended state, the direction in which the worm 250, the double stage gear 251, and the gears 252, 253, 254 of the rotation transmission mechanism 25 rotate, the direction in which the drive gear 24 rotates, and the direction in which the rotary drum 40 rotates are referred to as "forward directions", and the opposite direction to the forward directions, respectively.

Thus, when the rotary drum 40 is extended, the extended rotary drum 40 protrudes from the rear panel 1A (refer to fig. 1) of the smartphone 1. When the smartphone 1 is dropped or the like in this state, an impact is applied to the rotation barrel 40 protruding from the rear panel 1A, and the lens barrel module 2 is broken. Therefore, in the present embodiment, the acceleration sensor 5 detects the acceleration of the smartphone 1, and thus detects that the smartphone 1 starts to fall.

The control unit 4 receives the detection signal from the acceleration sensor 5, determines that the smartphone 1 starts to fall when an acceleration increase is detected, and transmits a control signal to the motor 21 of the drive unit 20 of the lens barrel module 2 to rotate the motor 21 in the opposite direction. The reverse rotation of the motor 21 is transmitted to the drive gear 24 by the rotation transmission mechanism 25, and the drive gear 24 rotates in the reverse direction. Thereby, the rotary drum 40 rotates in the opposite direction. At this time, as shown in fig. 10, the rotary drum 40 is rotated in the reverse direction until the protruding portion 45 of the rotary drum 40 comes out of the front end groove 33C of the cam groove 33 of the fixed drum 30 and enters the region of the spiral groove 33A. The time required for the protruding portion 45 of the rotary drum 40 to enter the region of the spiral groove 33A from the front end groove 33C is, for example, about 0.2 seconds to 0.3 seconds, and the motor 21 is rotated in the reverse direction during the time. The state of the lens barrel module 2 at this time is referred to as a "retracted state".

In such a retracted state, even if a force that pushes the rotary drum 40 back in the-Z direction by an impact applied to the rotary drum 40 due to the falling of the smartphone 1 or the like acts, the protruding portion 45 of the rotary drum 40 can move in the-Z direction along the spiral groove 33A of the fixed drum 30, and therefore the force that acts on the protruding portion 45 of the rotary drum 40 due to the impact can be reduced. Therefore, damage to the lens barrel module 2 due to impact applied to the rotation barrel 40 by dropping or the like of the smartphone 1 can be suppressed, and thus, malfunction of the smartphone 1 can be prevented.

In the present embodiment, by using the detection signal from the acceleration sensor 5, the rapid start of the position change associated with the falling of the smartphone 1 can be detected. Therefore, before the smartphone 1 is dropped to apply an impact to the rotary cylinder 40, the control unit 4 can rotate the rotary cylinder 40 in the opposite direction to bring the lens barrel module 2 into the retracted state. The timing of bringing the lens barrel module 2 into the retracted state is not limited to the timing at which the rapid position change is detected by the acceleration sensor 5 as described above, and the lens barrel module 2 may be brought into the retracted state at any timing (for example, when the state where no input from the user is continued for a predetermined time or the like) at which the impact is expected to be applied to the extended rotary cylinder 40.

Here, it is considered that if the impact applied to the rotary cylinder 40 is extremely large after the lens barrel module 2 is put into the retracted state, the torque exceeding the allowable range acts on the rotation transmission mechanism 25 and the motor 21 to cause breakage of the components of the rotation transmission mechanism 25 and the motor 21, but in the present embodiment, the torque limiter described above is included in the rotation transmission mechanism 25, and therefore if the torque generated by the impact applied to the rotary cylinder 40 exceeds a predetermined torque, the gear 252 and the gear 253 constituting the torque limiter slip to idle, and therefore breakage of the rotation transmission mechanism 25 and the motor 21 can be prevented.

Such a torque limiter is effective not only in the case of rotating the rotary drum 40 in the reverse direction to bring the lens barrel module 2 into the retracted state, but also in the case of applying an impact to the rotary drum to rotate the rotary drum in an undesired direction. In such a case, if the torque applied to the torque limiter exceeds a predetermined torque, the torque limiter cuts off the transmission of rotation between the drive gear 24 and the motor 21, and therefore breakage of the rotation transmission mechanism 25 and the motor 21 can be prevented.

In the present embodiment, the coil spring 255 biases the washer 256 disposed between the gear 252 and the gear 253, thereby forming the torque limiter, but the torque limiter is not limited to such a configuration, and any configuration may be used for the rotation transmission mechanism 25.

As described above, according to one aspect of the present utility model, there is provided a lens barrel module which is not easily broken even when an impact is applied thereto. The lens barrel module includes: a fixed cylinder having a cam groove formed in an inner peripheral surface thereof, the cam groove including a spiral groove extending in a spiral shape and a tip groove extending in a circumferential direction from a tip of the spiral groove; a rotary drum disposed radially inward of the fixed drum; and a driving unit that rotates the rotary cylinder. The rotary cylinder has at least one lens, a protruding portion protruding radially outward and engaging with the cam groove of the fixed cylinder, and a driven gear formed along a circumferential direction. The drive unit includes a motor, a drive gear engaged with the driven gear of the rotary drum, and a rotation transmission mechanism capable of transmitting rotation of the motor to the drive gear. The rotation transmission mechanism includes a torque limiter capable of cutting off transmission of rotation between the drive gear and the motor when a torque exceeding a predetermined value is applied.

According to this configuration, even when the rotary drum is rotated in an undesired direction by applying an impact to the rotary drum, if the torque applied to the torque limiter exceeds a predetermined torque, the torque limiter can cut off the transmission of rotation between the drive gear and the motor. Therefore, excessive force can be prevented from acting on the output shaft of the motor, and breakage of the motor can be prevented.

The torque limiter may include: a first gear formed to rotate in association with the rotation of the motor; a second gear that rotates in association with the rotation of the drive gear; a washer disposed between the first gear and the second gear; and a biasing member that biases the washer toward one of the first gear and the second gear, and rotates integrally with the other of the first gear and the second gear. According to this configuration, when a torque exceeding a predetermined torque is applied, the first gear and the second gear slip and idle, so that an excessive force can be prevented from acting on the components of the rotation transmission mechanism, and breakage of the components can be prevented.

According to another aspect of the present utility model, there is provided an electronic apparatus that is less prone to breakage even when a lens barrel module is subjected to an impact. The electronic device has: a lens barrel module including at least one lens; an image pickup device disposed on an optical axis of the at least one lens of the lens barrel module; and a control unit that can control driving of the lens barrel module. The lens barrel module includes: a fixed cylinder having a cam groove formed in an inner peripheral surface thereof, the cam groove including a spiral groove extending in a spiral shape and a tip groove extending in a circumferential direction at a tip of the spiral groove; a rotary drum disposed radially inward of the fixed drum; and a driving unit that rotates the rotary cylinder. The rotary cylinder has a protruding portion protruding radially outward and engaging with the cam groove of the fixed cylinder, and a driven gear formed along a circumferential direction. The drive unit includes: a motor; a drive gear engaged with the driven gear of the rotary drum; and a rotation transmission mechanism capable of transmitting rotation of the motor to the drive gear. The control unit is configured to: when the protruding portion of the rotary cylinder of the lens barrel module is positioned in the front end groove of the cam groove of the fixed cylinder, the motor is rotated in the opposite direction at a predetermined timing to move the protruding portion of the rotary cylinder to the spiral groove of the cam groove of the fixed cylinder.

According to this configuration, for example, by rotating the motor in the reverse direction at a timing immediately before the electronic apparatus drops, the protruding portion of the rotary cylinder can be moved to the spiral groove of the cam groove of the fixed cylinder, and the lens barrel module can be brought into the retracted state. In this retracted state, even if an impact is applied to the rotary drum due to dropping of the electronic device or the like, the protruding portion of the rotary drum can move in the axial direction along the spiral groove of the fixed drum, and therefore the force acting on the protruding portion of the rotary drum due to the impact can be reduced. Therefore, breakage of the lens barrel module due to the application of an impact to the rotating drum can be suppressed, thereby preventing malfunction of the electronic apparatus.

In this case, the electronic device may further include an acceleration sensor capable of detecting acceleration, and the control unit may be configured to: and driving the motor in a reverse direction based on a detection signal from the acceleration sensor to move the protruding portion of the rotary cylinder of the lens barrel module toward the spiral groove of the cam groove of the fixed cylinder. By using such a detection signal from the acceleration sensor, it is possible to detect that a sudden position change such as a drop of the electronic device starts, and therefore, before an impact is applied to the rotary drum due to the sudden position change, the control unit can rotate the rotary drum in the opposite direction to bring the lens barrel module into the retracted state. Therefore, even if an impact is applied to the rotary drum thereafter, the force acting on the protruding portion of the rotary drum is reduced, and therefore breakage of the lens barrel module can be suppressed, thereby preventing malfunction of the electronic apparatus.

The rotation transmission mechanism of the lens barrel module may include a torque limiter capable of cutting off transmission of rotation between the motor and the drive gear when a torque exceeding a predetermined value acts on the torque limiter. According to this configuration, even when the rotary drum is rotated in the opposite direction by applying an impact to the rotary drum, if the torque applied to the torque limiter exceeds a predetermined torque, the torque limiter can cut off the transmission of rotation between the drive gear and the motor. Therefore, excessive force can be prevented from acting on the output shaft of the motor, thereby preventing breakage of the motor.

The torque limiter of the lens barrel module may include: a first gear formed to rotate in association with the rotation of the motor; a second gear that rotates in association with the rotation of the drive gear; a washer disposed between the first gear and the second gear; and a biasing member that biases the washer toward one of the first gear and the second gear, and rotates integrally with the other of the first gear and the second gear. According to this configuration, when a torque exceeding a predetermined value is applied, the first gear and the second gear slip and idle, so that excessive force can be prevented from acting on the components of the rotation transmission mechanism, and breakage of the components can be prevented.

The preferred embodiments of the present utility model have been described, but the present utility model is not limited to the above-described embodiments, and may be implemented in various modes within the scope of the technical ideas.

Claims (6)

1. A lens barrel module is characterized in that,

the lens barrel module includes:

a fixed cylinder having a cam groove formed in an inner peripheral surface thereof, the cam groove including a spiral groove extending in a spiral shape and a tip groove extending in a circumferential direction from a tip of the spiral groove;

a rotary cylinder disposed radially inward of the fixed cylinder, the rotary cylinder having at least one lens, a protruding portion protruding radially outward and engaged with the cam groove of the fixed cylinder, and a driven gear formed along a circumferential direction; and

and a drive unit that rotates the rotary drum, the drive unit including a motor, a drive gear that meshes with a driven gear of the rotary drum, and a rotation transmission mechanism that is capable of transmitting rotation of the motor to the drive gear, the rotation transmission mechanism including a torque limiter that is capable of cutting off transmission of rotation between the drive gear and the motor when a torque exceeding a predetermined torque acts thereon.

2. The lens barrel module according to claim 1, wherein,

the torque limiter comprises:

a first gear that rotates in association with rotation of the motor;

a second gear that rotates in association with rotation of the drive gear;

a washer disposed between the first gear and the second gear; and

and a biasing member that biases the washer toward one of the first gear and the second gear, and rotates integrally with the other of the first gear and the second gear.

3. An electronic device, characterized in that,

the electronic device has:

a lens barrel module including at least one lens;

an image pickup element disposed on an optical axis of the at least one lens of the lens barrel module; and

a control section capable of controlling driving of the lens barrel module,

the lens barrel module has:

a fixed cylinder having a cam groove formed in an inner peripheral surface thereof, the cam groove including a spiral groove extending in a spiral shape and a tip groove extending in a circumferential direction from a tip of the spiral groove;

a rotary cylinder disposed radially inward of the fixed cylinder, the rotary cylinder having a protruding portion protruding radially outward and engaging with the cam groove of the fixed cylinder, and a driven gear formed along a circumferential direction; and

a drive unit that rotates the rotary cylinder, and that has a motor, a drive gear that meshes with the driven gear of the rotary cylinder, and a rotation transmission mechanism that is capable of transmitting rotation of the motor to the drive gear,

the control unit is configured to: when the protruding portion of the rotary cylinder of the lens barrel module is located in the front end groove of the cam groove of the fixed cylinder, the motor is rotated in the opposite direction at a predetermined timing to move the protruding portion of the rotary cylinder to the spiral groove of the cam groove of the fixed cylinder.

4. The electronic device of claim 3, wherein the electronic device comprises a plurality of electronic devices,

the electronic device also has an acceleration sensor capable of detecting acceleration,

the control unit is configured to: the motor is rotated in the reverse direction in accordance with a detection signal from the acceleration sensor to move the protruding portion of the rotary cylinder of the lens barrel module toward the spiral groove of the cam groove of the fixed cylinder.

5. The electronic device of claim 3, wherein the electronic device comprises a plurality of electronic devices,

the rotation transmission mechanism of the lens barrel module includes a torque limiter capable of cutting off transmission of rotation between the motor and the drive gear when a torque exceeding a prescribed torque acts.

6. The electronic device of claim 5, wherein the electronic device comprises a memory device,

the torque limiter of the lens barrel module includes:

a first gear that rotates in association with rotation of the motor;

a second gear that rotates in association with rotation of the drive gear;

a washer disposed between the first gear and the second gear; and

and a biasing member that biases the washer toward one of the first gear and the second gear, and rotates integrally with the other of the first gear and the second gear.