KR101581220B1 - Transmission structure for protecting driving motor and photographing apparatus comprising the same - Google Patents

Abstract

The present invention provides a rotary shaft having a rotary shaft on which a first fixing member is mounted at an intermediate portion and a second fixing member is mounted at one end thereof and a first coupling portion formed in an axial direction of the rotary shaft and including a slope shape, And a second engaging portion formed to be engageable with the first engaging portion and having a shape of a slope, wherein the second engaging portion is constrained to the rotational movement of the rotation shaft and slides in the axial direction of the rotation shaft A first elastic member disposed between the first fixing member and the torque limiting member so as to be able to slide in the axial direction of the rotary shaft while being restricted by the rotary motion of the rotary shaft; A moving gear mounted on the rotating shaft, and a second elastic member disposed between the second fixing member and the moving gear, It provides also the power transmitting structure and an imaging device having the same that.

A power transmission structure,

Description

TECHNICAL FIELD [0001] The present invention relates to a power transmission structure for protecting a driving motor and an imaging apparatus having the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmitting structure, and more particularly, to a power transmitting structure for protecting a driving motor.

2. Description of the Related Art [0002] An image pickup apparatus is an apparatus for picking up an image of a subject. Recently, image pickup apparatuses such as digital still cameras and digital video cameras have been widely used.

The imaging device often incorporates an auto-focusing function that automatically adjusts the focus. However, advanced users and users seeking an older style often prefer an imaging device with manual focus as well as autofocus. Therefore, in recent years, many imaging apparatuses including an autofocus function and a manual focus function are commercially available.

In general, an imaging device having such functions has a switch button on the lens barrel, and when the user operates the switch button, the switch is switched from the auto focus function to the manual focus function or from the manual focus function to the auto focus function Respectively.

Hereinafter, the operation of a conventional image pickup apparatus capable of such a switching operation will be described in detail.

That is, when the user places the switch button in the "auto focus" position to use the auto focus function, the power transmission gear of the drive motor and the ring gear of the lens barrel are directly engaged and power is transmitted from the drive motor to the ring gear It was possible to perform an auto focus operation.

In addition, when the user places the switching button in the " manual focus " position to use the manual focusing function, the user disconnects the power transmission gear of the driving motor from the ring gear of the lens barrel, I could grab and turn the focus manually.

However, there has been a case where, while using the above-described image pickup apparatus, the drive motor that performs the auto-focus function while the user is blinking and manipulating the position of the changeover button is broken.

That is, although the position of the switch button is at the position of " manual focus ", the user considers the position of the switch button to be the position of " auto focus " . However, when the position of the switch button is in the position of " auto focus ", the user thinks that the position of the switch button is the position of " manual focus " The excessive torque acts on the drive motor directly, which may cause the drive motor to break.

Therefore, in the above case, that is, even if the position of the switch button is at the position of " auto focus ", the user thinks that the position is the " manual focus " It is necessary to develop the technology.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a power transmitting structure capable of protecting a driving motor that performs an auto focus function and an image pickup apparatus having the same.

The present invention relates to an image forming apparatus having a rotary shaft on which a first fixing member is mounted at an intermediate portion and a second fixing member is mounted at an end thereof and a first coupling portion formed in an axial direction of the rotary shaft and including a slope shape, And a second engaging portion formed to be engageable with the first engaging portion and having a slope shape, wherein the second engaging portion is constrained to the rotation movement of the rotation axis, A first elastic member disposed between the first fixing member and the torque limiting member, and a second elastic member disposed between the first fixing member and the torque limiting member, the first elastic member being constrained to the rotational movement of the rotation shaft, And a second elastic member disposed between the second fixing member and the moving gear, It provides a power transmission structure including a;

Here, the action gear can be engaged with the ring gear.

Here, a guide protrusion may be formed on the rotary shaft, and a sliding groove may be formed on an inner circumference of the torque limiting member to receive the guide protrusion.

Here, the inner circumference of the torque limiting member may be formed with a first engaging step for engaging one end of the first elastic member.

Here, the first elastic member may be a cylindrical coil spring.

The apparatus may further include a button assembly for moving the moving gear in contact with the moving gear.

Here, the button assembly may include a button and a support member connected to the button to move the movement gear.

Here, the moving gear may be located at a first position or a second position according to the movement of the button assembly, and when the moving gear is at the first position, And when the moving gear is in the second position, the moving gear can be disengaged from the first driving gear.

Here, the moving gear may be engaged with a first driving gear that receives power from the driving motor.

Here, a second stopping jaw may be formed on the inner circumference of the moving gear so that one end of the second elastic member is hooked.

Further, the image pickup apparatus according to the present invention may include the above-described power transmitting structure.

According to the power transmission structure of the present invention, the drive motor can be protected.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic perspective view of an image pickup apparatus according to an embodiment of the present invention, and Fig. 2 is a side view showing a side surface of the lens unit of Fig. 1. Fig.

As shown in FIG. 1, the imaging apparatus 100 according to the present embodiment is a single-lens reflex camera, and is a digital camera capable of attaching and detaching the lens unit 110 as needed.

On the other hand, the imaging apparatus 100 according to the present embodiment is a single-lens reflex camera, but the present invention is not limited thereto. That is, the type and the format of the image pickup apparatus according to the present invention are not particularly limited. For example, in the image pickup apparatus according to the present invention, various kinds and types of image pickup apparatuses such as a compact camera and an image camcorder can be applied.

The image pickup apparatus 100 mainly includes a lens unit 110 and a main body 120.

The lens unit 110 includes a lens group 111 and a lens barrel 112 and transmits the image light of the subject to the main body 120.

The lens group 111 functions to transmit an image light of a subject, and includes a zoom lens, a focus lens, a diaphragm, and the like. Among them, the zoom lens is a lens in which the focal length continuously changes by moving back and forth in the direction of the optical axis, and is a lens for changing the size of the subject, and the focus lens is a lens for focusing. The diaphragm is a device for adjusting the amount of light entering the image pickup element when photographing a subject.

As shown in Figs. 1 and 2, a button 113a is disposed on one side of the lens unit 110. Fig.

Button 113a may be positioned in one of two states of "auto-focusing" and "manual-focusing". That is, when the button 113a is in the " auto-focus function state ", it is automatically focused, and when the button 113a is in the " manual focus function state ", when the user holds the outer periphery of the lens- Focus. That is, although not shown, when the lens barrel 112 is rotated, the inner cam member is also rotated so that the distance of the focus lens in the lens barrel 112 is changed and can be focused. Known technology.

The main body 120 includes a shutter, an imaging device, an image processing unit, a viewfinder, and a control unit that performs an auto focus function and controls an internal motor.

The main body 120 receives image light via the lens unit 110 and performs imaging.

Hereinafter, the power transmission system according to the present embodiment will be described with reference to FIG. 3 to FIG.

3 is a perspective view showing an assembly state of a ring gear, a power transmitting structure, a button, a drive gear assembly, and a drive motor of a lens barrel according to an embodiment of the present invention. FIG. 4 is an assembled perspective view showing the support member, the power transmission structure, the drive gear assembly, and the drive motor among the components shown in FIG. 3, and FIG. 5 is a plan view of FIG. Fig. 6 is an exploded perspective view of the power transmitting structure according to the present embodiment, and Fig. 7 is an exploded perspective view of Fig. 6 taken at another angle. 8 is a front view of the torque limiting member shown in Fig. 6 as viewed from the axial direction of the rotation shaft.

3 to 5, the power transmission system according to the present embodiment includes a ring gear 112a, a button assembly 113, a power transmission structure 130, a drive gear assembly 140, a drive motor 150 ).

The ring gear 112a is formed on the inner periphery of the lens barrel 112 and functions to rotate the lens barrel 112. [

The button assembly 113 includes a button 113a and a support member 113b connected to the button 113a. The support member 113b has a function of moving the moving gear 137 in accordance with the movement of the button 113a .

6 and 7, the power transmitting structure 130 includes a rotating shaft 131, a first fixing member 132, a second fixing member 133, a working gear 134, a torque limiting member 135, a first elastic member 136, a moving gear 137, and a second elastic member 138.

The rotary shaft 131 is rotatably mounted on an inner frame (not shown) of the lens unit 110. A fixing groove 131a is formed in the intermediate portion of the rotating shaft 131 and a guide protrusion 131c is formed between the first end 131b and the fixing groove 131a. Further, a D-cut portion 131e is formed between the second end portion 131d of the rotary shaft 131 and the fixing groove 131a. The D-cut portion 131e is formed by cutting a portion of the outer surface of the second end portion 131d.

The first fixing member 132 has a ring shape and is fitted and fixed in the fixing groove 131a.

The second fixing member 133 is fitted and fixed to the second end 131d of the rotary shaft 131. [

The action gear 134 is mounted on the rotating shaft 131 so as to be slidable. That is, the inner diameter of the mounting hole 134a of the operating gear 134 is formed to be larger than the outer diameter of the rotating shaft 131 so that it can rotate independently of the rotating action of the rotating shaft 131.

The operating gear 134 has a spur gear shape as a whole, and a first engaging portion 134b formed on one side thereof in the axial direction of the rotating shaft 131 is formed.

The first engaging portion 134b includes a shape of a slope inclined in the axial direction of the rotating shaft 131. [ The shape of the slope is formed by repeating the shape of the convex and the concave. The design of the slope will be described later.

The torque limiting member 135 has a cylindrical shape and is configured to rotate together with the rotation axis 131 and to be able to slide in the axial direction of the rotation axis 131 while being restricted by the rotation movement of the rotation axis 131. [ To this end, as shown in Fig. 8, a first engaging protrusion 135a and a sliding groove 135b are formed on the inner circumference of the torque limiting member 135. [ The guide protrusion 131c of the rotary shaft 131 is engaged with the sliding groove 135b of the torque limiting member 135 so that the torque limiting member 135 is constrained to the rotary motion of the rotary shaft 131, The torque limiting member 135 rotates together with the rotating shaft 131 so that the torque limiting member 135 can slide in the axial direction of the rotating shaft 131. [

The torque limiting member 135 is designed to be smaller than the length of the sliding groove 135b but the torque limiting member 135 slides to contact the moving gear 137 to push the moving gear 137 It is designed such that the moving gear 137 can be sufficiently pushed until the engagement between the moving gear 137 and the first driving gear 141 is released.

On the other hand, the torque limiting member 135 is formed with a second engaging portion 135c so as to be engageable with the first engaging portion 134b. The second engaging portion 135c is formed to face the first engaging portion 134b and includes the shape of a slope inclined in the axial direction of the rotating shaft 131. The shape of the slope is a shape in which convex and concave shapes are repeated So that it can be coupled with the first coupling portion 134b.

Since the first engaging portion 134b and the second engaging portion 135c include a slope shape, the convex portion of the first engaging portion 134b and the concave portion of the second engaging portion 135c, When the convex portion of the first engaging portion 134b and the convex portion of the second engaging portion 135c are engaged and a torque exceeding a predetermined size is applied, the first engaging portion 134b and the second engaging portion 135c ) Are separated from each other by moving on slopes facing each other, and the distances from each other become far apart. Details related to them will be described later.

On the other hand, the first elastic member 136 is disposed between the first fixing member 132 and the torque limiting member 135.

A cylindrical coil spring is used as the first elastic member 136. One end 136a of the first elastic member 136 is caught by the first engagement protrusion 135a of the torque limiting member 135, 136b are configured to be caught by the first fixing member 132. [

The first elastic member 136 is compressed and installed so as to have a predetermined elastic force when assembled. Therefore, in the assembled power transmitting structure 130, the elastic force of the first elastic member 136 pushes the torque limiting member 135 toward the action gear 134, so that the first engagement portion 134b and the second engagement portion 135c are assembled so as to maintain mutual engagement.

Here, the spring coefficient K of the first elastic member 136 and the displacement? Of the first elastic member 136 compressed during assembly must be appropriately determined. This is because the torque limiting member 135 is urged by a predetermined elastic force To engage with the action gear 134. In designing the characteristics of the first elastic member 136, the shape of the slopes of the first engagement portion 134b and the second engagement portion 135c should also be considered.

The design of the first elastic member 136 according to the present embodiment and the design of the shape of the slopes of the first engagement portion 134b and the second engagement portion 135c will be described with reference to Fig.

9 is a schematic sectional view showing an elastic force, a normal force, and a frictional force acting on the slopes of the first engagement portion 134b according to the present embodiment. The angle of the slope of the first coupling portion 134b is strictly a value slightly varying depending on the position, but it is assumed here that it has a certain value of? For the sake of understanding.

As described above, since the slope of the first engaging portion 134b and the slope of the second engaging portion 135c are mutually coupled, their shapes are opposite to each other and have the same shape. Therefore, the corresponding vertical force and frictional force also correspond to each other and therefore, the design of the shape of the slope of the first engagement portion 134b will be described below.

As described above, when assembling the power transmitting structure 130 according to the present embodiment, the elastic force generated when the first elastic member 136 is compressed and pressed to some extent causes the torque limiting member 135 to move toward the action gear 134 .

When that happens, the first to spring force F _s acting as a compressed amount of change in the resilient member (136) (δ), such a spring force F _s has been pushed a torque limiting member 135 by the action gear (134) direction, the second coupling A load acts on the slope of the first engaging portion 134b from the slope of the portion 135c. That is, when the spring coefficient of the first elastic member 136 is K, the following equation (1) holds. Here, it is assumed that the spring coefficient K has a linear property.

On the other hand, it is assumed that the number of slopes constituting the first coupling portion 134b is n. Here, the normal force f _n acting on each of the n slopes can be expressed by the following equation (2) using the elastic force F _s . Here,? Denotes an angle between a line segment perpendicular to the slope and a line segment in the direction of the rotation axis 131, and is also an angle at which the slope is formed.

The frictional force f _f acting on each slope of the first engagement portion 134b can be expressed by the following Equation 3 using the friction coefficient mu.

Therefore, the total frictional force F _f acting on the slope of the first coupling portion 134b can be expressed by Equation (4) using Equations (1), (2) and (3)

When the distance from the slope to the center of the rotary shaft is R, the friction torque T _f can be expressed by the following equation (5).

Therefore, when the shape design of the surface of the first coupling part (134b), the frictional force F _f is higher than the torque T _normal in the normal load state, the first engaging portion (134b) surface and the second engagement portion (135c in during normal driving So that slippage between the slopes does not occur and the power can be transmitted.

On the contrary, due to an excessive external load that acts by the user inadvertently turning the lens barrel 112 in the " auto-focus function state " by force, the inner rotor of the drive motor 150 is damaged If the limit torque T _limit is applied, the frictional torque T _f must be smaller than the limit torque T _{limit so} that a slipping action occurs between the first engaging portion 134b and the second engaging portion 135c. In this case, since it is possible to protect the driving motor 150 by preventing the transmission of the power, the following equation (6) must be satisfied when designing the slope.

Therefore, the designer determines the torque T _{normal in the} normal load condition and the limit torque T _limit that can not protect the drive motor 150, and accordingly, the first engagement portion 134b and the second engagement portion 135c, The friction coefficient μ of the slope material of the first engaging portion 134b and the second engaging portion 135c, the spring coefficient K of the first elastic member 136, the amount of spring change δ And the design parameters of the system are determined appropriately.

Meanwhile, the moving gear 137 is configured to be slidable in the axial direction of the rotating shaft 131 while being restricted by the rotating motion of the rotating shaft 131, which will be described with reference to FIG.

10 is a front view of the moving gear shown in Fig. 6 as seen from the axial direction of the rotating shaft.

As shown in Fig. 10, the second engaging protrusion 137a and the D-cut corresponding hole 137b are formed on the inner periphery of the moving gear 137. As shown in Fig. The D-cut corresponding hole 137b of the moving gear 137 has a shape corresponding to the sectional shape of the D-cut portion 131e of the rotating shaft 131. [ Therefore, the D-cut portion 131e of the rotating shaft 131 is fitted in the D-cut corresponding hole 137b of the moving gear 137, so that the moving gear 137 is restricted by the rotational movement of the rotating shaft 131, The rotating shaft 131 rotates together with the moving gear 137 as well. Further, the moving gear 137 can be slid in the axial direction of the rotating shaft 131.

The support gear 113b of the button assembly 113 is in contact with the outside of the one side portion 137c of the moving gear 137 and is in contact with the moving gear 137, .

On the other hand, the second elastic member 138 is disposed between the second fixing member 133 and the moving gear 137.

A cylindrical coil spring is used as the second elastic member 138. One end 138a of the second elastic member 138 is caught by the second engagement protrusion 137a of the moving gear 137 and the other end 138b Is configured to be caught by the second fixing member 133.

The second elastic member 138 is compressed and installed so as to have a predetermined elastic force when assembled. Therefore, in the assembled power transmitting structure 130, the elastic force of the second elastic member 138 acts to push the moving gear 137 toward the first fixing member 132.

4 and 5, the driving gear assembly 140 includes a first driving gear 141, a second driving gear 142, and a connecting shaft 143. Here, the first drive gear 141 and the second drive gear 142 have the shape of a spur gear.

 The first driving gear 141 is configured to engage with the moving gear 137 when the position of the button 113a is in the " autofocus function state ".

The second driving gear 142 is configured to engage with the motor shaft gear 151a and the connecting shaft 143 is configured to connect the first driving gear 141 and the second driving gear 142. [

A stepping motor or a stepping motor is used as the driving motor 150. A motor shaft gear 151a meshing with the second driving gear 142 is mounted on the motor shaft 151 of the driving motor 150 .

Hereinafter, the operation of the power transmitting structure 130 according to the present embodiment will be described with reference to FIGS. 11 to 13. FIG.

Fig. 11 is a schematic cross-sectional view showing a state in which power is transmitted to the power transmitting structure when the position of the button of the image pickup apparatus according to the present embodiment is in the auto-focus function state, and Fig. Is a schematic cross-sectional view showing the appearance of the power transmitting structure when the position of the button is in the manual focus function state. 13 shows a state in which the position of the button of the image pickup apparatus according to the present embodiment is in the autofocus function state, but when the user turns the lens barrel forcibly, the first engaging portion and the second engaging portion are disengaged, Fig. 5 is a cross-sectional view showing a state in which the engagement of the gears is released.

First, with reference to Fig. 11, the operation of positioning the button 113a in the " autofocus function state " by the user and performing imaging using the autofocus function will be described.

When the user places the position of the button 113a in the " auto focus function state ", the moving gear 137 is engaged with the first driving gear 141 as shown in Fig. Here, the position of the moving gear 137 when the moving gear 137 is engaged with the first driving gear 141 is referred to as a first position. In this case, a control unit (not shown) of the main body 120 performs an auto focus algorithm by a switch (not shown) in the button 113a.

In this case, the control unit (not shown) of the main body 120 operates the driving motor 150, and receives the image light at that time in an image pickup element (not shown) The power is transmitted from the lens barrel 150 to the ring gear 112a of the lens barrel 112.

In this case, the path through which the power is transmitted is as follows.

That is, when the motor shaft gear 151a of the driving motor 150 rotates, the second driving gear 142 that meshes therewith rotates. When the second driving gear 142 rotates, the first driving gear 141 rotates, When the first gear 141 rotates, the moving gear 137 rotates. When the moving gear 137 rotates, the rotating shaft 131 rotates. When the rotating shaft 131 rotates, The torque limiting member 135 is rotated. When the torque limiting member 135 is rotated, the action gear 134 is rotated. When the action gear 134 is rotated, the ring gear 112a is rotated When the ring gear 112a rotates, the lens barrel 112 rotates, so that the distance of the focus lens can be changed so that a focusing operation can be performed.

As described above, by the spring coefficient K of the first elastic member 136 and the initial setting at the time of assembly, the engagement between the first engagement portion 134b and the second engagement portion 135c is established by the ring gear 112a ), and because it is constructed to withstand the normal torque load T _normal of the lens barrel 112, the power of the working gear 134 and the torque limiter member 135 engaged state is maintained, the driving motor 150 of the ring gear So that it can be transmitted without fail.

Next, with reference to Fig. 12, the user seeks to position the position of the button 113a in the " manual focusing function state ", and to perform the imaging using the manual focusing function.

When the user changes the position of the button 113a from the "auto focus function state" to the "manual focus function state", the support member 113b pushes the moving gear 137 to the right side , So that the moving gear 137 is disengaged from the first driving gear 141. Here, the position of the moving gear 137 when the moving gear 137 is disengaged from the first driving gear 141 is referred to as a second position. When the button 113a reaches the position of the " manual focusing function state ", the stopper (not shown) temporarily locks the button 113a so that the moving gear 137 can be temporarily fixed to the second position do. In this case, a control unit (not shown) of the main body 120 stops the automatic focusing operation by a switch (not shown) in the button 113a.

In the case of the manual focusing operation, the user directly adjusts the focus by rotating the lens barrel 112 while looking at the subject with a viewfinder (not shown). In this case, the path through which the power is transmitted from the lens barrel 112, As follows.

That is, when the user turns the lens barrel 112, the ring gear 112a rotates, and when the ring gear 112a rotates, the action gear 134 engaging with the ring gear 112a rotates, The torque limiting member 135 coupled to the rotation limiting member 135 rotates to rotate the rotation shaft 131. When the rotation shaft 131 rotates, . Even if the moving gear 137 rotates as described above, since the engagement of the moving gear 137 and the first driving gear 141 is released by the movement of the supporting member 113b, 141). ≪ / RTI >

12, the user operates the button 113a as " auto-focus " and " auto focus " Functional state " and the lens barrel 112 is forcibly turned to focus.

It is assumed that the user forcibly rotates the lens barrel 112 while the user places the button 113a in the " auto-focus function state "

In this case, when the user turns the lens barrel 112, the ring gear 112a rotates, and when the ring gear 112a rotates, the action gear 134 engaging with the ring gear 112a rotates.

The engagement condition between the first engaging portion 134b and the second engaging portion 135c is determined by the spring coefficient K of the first elastic member 136 and the initial setting at the time of assembling, And the normal torque load T _normal of the lens barrel 112, as shown in Fig. However, when the user forcibly turns the lens barrel 112 in the " auto-focus function state " as described above, the limit torque T _limit is exceeded so that the engagement state of the action gear 134 and the torque limiting member 135 . That is, since the slope of the second engaging portion 135c slides on the slope of the first engaging portion 134b, the torque limiting member 135 moves to the right side because it exceeds the limit torque T _limit .

When the torque limiting member 135 is moved to the right side, the torque limiting member 135 pushes the end portion 137c_1 of the moving gear 137 to the right, and the moving gear 137 is rotated by the first driving gear 141 ) Is released in the second position.

Even if the ring gear 112a and the action gear 134 rotate abnormally by the user turning the lens barrel 112 forcibly, the engagement state of the action gear 134 and the torque restricting member 135 The torque limiting member 135 is not rotated. The torque limiting member 135 pushes the moving gear 137 to the right side through the releasing process of the engagement of the operating gear 134 and the torque limiting member 135 to move the moving gear 137 and the first driving gear 141 So that the power from the drive motor 150 is not transmitted to the moving gear 137. As a result, In this case, even if the user mistakenly turns the lens barrel 112 in the " auto-focus function state ", the transmission of the power is cut off in two, so that the driving motor 150 can be protected.

Here, if the user realizes his mistake and does not turn the lens barrel 112, the first elastic member 136 that has been compressed is rotated to push the torque limiting member 135 to the left, 134b and the second engagement portion 135c are resumed. Also, the moving gear 147 that has moved to the right moves again to the left while the second elastic member 138 that has been compressed is rotated, and the engagement with the first driving gear 141 is resumed. Therefore, the state returns to the state shown in Fig. 11 as a whole.

As described above, according to the power transmitting structure 130 of the present embodiment, even if a user mistakenly applies a load exceeding the limit torque T _limit to the lens barrel 112, the transmission of power is automatically interrupted, There is an advantage that the motor 150 can be protected.

The power transmitting structure 130 according to the present embodiment has been applied to the image capturing apparatus 100 capable of switching to either the "auto focus function state" or the "manual focus function state" according to the movement of the button 113a , But the present invention is not limited thereto. That is, the power transmitting structure relating to the present invention can be applied to an imaging apparatus having only " autofocus function state ". In this case, the power transmitting structure can protect the driving motor even if an external shock and an overload torque to the lens barrel that may occur during the auto focus operation occur.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. It will be possible. Accordingly, the true scope of protection of the present invention should be determined only by the appended claims.

1 is a schematic perspective view of an image pickup apparatus according to an embodiment of the present invention.

2 is a side view showing a side surface of the lens unit of Fig. 1;

3 is a perspective view showing an assembly state of a ring gear, a power transmitting structure, a button, a drive gear assembly, and a drive motor of a lens barrel according to an embodiment of the present invention.

4 is an assembled perspective view showing the support member, the power transmission structure, the drive gear assembly, and the drive motor among the components shown in Fig.

5 is a plan view of Fig.

6 is an exploded perspective view of a power transmitting structure according to an embodiment of the present invention.

Fig. 7 is an exploded perspective view of Fig. 6 taken at another angle.

8 is a front view of the torque limiting member shown in Fig. 6 as viewed from the axial direction of the rotation shaft.

9 is a schematic cross-sectional view showing an elastic force, a normal force, and a frictional force acting on a slope of a first engaging part according to an embodiment of the present invention.

10 is a front view of the moving gear shown in Fig. 6 as seen from the axial direction of the rotating shaft.

11 is a schematic cross-sectional view showing that power is transmitted to the power transmitting structure when the position of the button of the image pickup apparatus according to the embodiment of the present invention is in the auto focus function state.

12 is a schematic cross-sectional view showing the appearance of the power transmitting structure when the position of the button of the image pickup apparatus according to the embodiment of the present invention is in the manual focus function state.

FIG. 13 is a view illustrating a state in which the position of the button of the image pickup apparatus according to the embodiment of the present invention is in the auto focus function state, but when the user turns the lens barrel forcibly, the first engaging portion and the second engaging portion are disengaged, Fig. 5 is a cross-sectional view showing a state in which the meshing of the driving gear is released.

Description of the Related Art

100: image pickup device 110: lens unit

111: lens group 112: lens barrel

112a: ring gear 113: button assembly

113a: Button 113b: Support member

120: main body 130: power transmission structure

131: rotation shaft 132: first fixing member

133: second fixing member 134: operating gear

134b: first engaging portion 135: torque limiting member

135c: second coupling portion 136: first elastic member

137: moving gear 138: second elastic member

140: drive gear assembly 141: first drive gear

142: second driving gear 143: connecting shaft

150: drive motor 151: motor shaft

151a: motor shaft gear

Claims (11)

A rotary shaft having a first fixing member mounted at an intermediate portion thereof, a second fixing member mounted at one end thereof, a guide protrusion protruding outwardly, and a cutout portion having a portion of the outer surface thereof cut away; A working gear mounted on the rotating shaft to have a first engaging portion formed in an axial direction of the rotating shaft and including a shape of a slope and to be slidable in the circumferential direction about a shaft center of the rotating shaft; A second engaging portion formed to be engageable with the first engaging portion and including a shape of a slope and a sliding groove into which the guide protrusion is inserted so as to surround the outer surface of the rotating shaft, A torque limiting member mounted on the rotating shaft so as to rotate together with the rotating shaft and to slide in an axial direction of the rotating shaft; A first elastic member disposed between the first fixing member and the torque limiting member; And a hole corresponding to the cross-sectional shape of the cutout portion of the rotary shaft so as to fit the incision portion of the rotary shaft, wherein the rotary shaft is mounted on the rotary shaft so as to rotate together with the rotary shaft and to slide in the axial direction of the rotary shaft Moving gear; And And a second elastic member disposed between the second fixing member and the moving gear. The method according to claim 1, And the action gear is engaged with the ring gear. delete The method according to claim 1, And a first engaging step for engaging one end of the first elastic member is formed on the inner circumference of the torque limiting member. The method according to claim 1, Wherein the first elastic member is a cylindrical coil spring. The method according to claim 1, Further comprising a button assembly for moving said moving gear in contact with said moving gear. The method according to claim 6, Wherein the button assembly includes a button and a support member connected to the button to move the gear. The method according to claim 6, The moving gear may be located at a first position or a second position according to the movement of the button assembly, A first drive gear that transmits power is engaged with the moving gear when the moving gear is in the first position, And the shift gear is disengaged from the first drive gear when the shift gear is in the second position. The method according to claim 1, And the moving gear is engaged with a first driving gear that receives power from the driving motor. The method according to claim 1, And a second engaging step for engaging one end of the second elastic member is formed on the inner periphery of the moving gear. An image pickup apparatus comprising the power transmitting structure according to any one of claims 1 to 2 or any one of claims 4 to 10.

Images