JP5517654B2 - Lens barrel and imaging device - Google Patents

Description

  The present invention relates to a technique for improving light shielding, design freedom, and operation accuracy in a lens barrel used in an imaging apparatus such as a digital camera.

  In the lens barrel, a configuration is known in which the front and rear lens group barrels are cam-engaged and the rotation of the front and rear groups is regulated by a guide member having a key for regulating rectilinear advance. In the photographic lens barrel disclosed in Patent Literature 1, an outer peripheral portion located radially outward from the rectilinear key is cut out in a cam ring that rotates relatively adjacent to the rectilinear key.

JP 2007-219304 A

Conventional lens barrels have problems with respect to light shielding against external light and the degree of freedom in designing the arrangement of interlocking portions of the cam ring. In the configuration shown in Patent Document 1, since the outer peripheral portion of the cam ring is cut out, if the external light that has entered the lens barrel passes through the outer periphery of the cam ring and reaches the image sensor, the captured image is affected. There is a risk of affecting. In addition, since there is a limitation on the interlocking portion arrangement of the cam ring interlocking with the adjacent member, a low degree of freedom in design becomes a problem.
Accordingly, an object of the present invention is to increase the degree of freedom in designing the light shielding property against external light and the arrangement of interlocking portions of the cam ring.

In order to solve the above problems, the present invention provides a lens barrel having a first lens group and a second lens group that are movable in the optical axis direction, the first holding member of the first lens group . in the first cam member when the cam engagement with holding the first holding member, the rotation of the a movable said to the first cam member integrally with the optical axis direction first holding member a first regulating member for regulating a second cam member for holding the second holding member cam engagement with the second holding member of the second lens group, and the second cam member A second restricting member that is integrally movable in the optical axis direction and restricts the rotation of the second holding member; and a third cam member that guides the first cam member and the second cam member. And comprising. Wherein the first regulating member, the first flange portion which extends in a direction extends to the inner peripheral surface of the third cam member which is perpendicular to the optical axis of the first lens group is formed, the first The second restricting member is formed with a second flange portion extending in a direction orthogonal to the optical axis of the second lens group and extending to the inner peripheral surface of the third cam member. The flange portion is cam-engaged with the third cam member, and the second flange portion is cam-engaged with the third cam member .

  According to the present invention, it is possible to increase the degree of freedom in designing the arrangement of the interlocking portions of the cam ring, and the internal light shielding property is high with respect to external light entering the lens barrel.

It is a center sectional view showing an example of composition of a lens barrel concerning one embodiment of the present invention. It is a schematic diagram which shows the cam locus | trajectory of a lens barrel. It is a disassembled perspective view which shows the structural example of the zoom mechanism system of a lens barrel. FIG. 3 is an exploded perspective view illustrating a configuration example of a peripheral portion of a zoom mechanism driving system, a focus driving system, and an imaging element of a lens barrel. FIG. 5 is a central cross-sectional view showing a configuration of a lens barrel in order to explain a light shielding effect and a strength improving effect. In order to describe a configuration that increases the degree of freedom in design, it is a front view and a central sectional view showing positions of the second group cam ring 126, the second group rectilinear ring 127, and the guide plate 128 at the wide end. FIG. 6 is a cross-sectional view of a main part showing a moving cam ring 123 and a first group rectilinear ring 125 in order to explain the effect of improving the barrel strength by the flange portion.

  Hereinafter, a configuration example of an apparatus including a three-stage retractable lens barrel will be described as an embodiment according to the imaging apparatus of the present invention. FIG. 1 is a central sectional view of the lens barrel cut along the optical axis, and the outline of the configuration of the lens barrel will be described based on this drawing. The photographing optical system includes a first lens group (hereinafter referred to as “first group”) 101, a second lens group (hereinafter referred to as “second group”) 102, and a third lens group (hereinafter referred to as “third group”) 103. Each lens group is generally composed of a plurality of optical members, and the third group 103 (single lens in this example) is positioned in front of the image sensor 104. The image sensor 104 converts a subject image formed through each lens group into an electric signal, and outputs the image signal to a signal processing circuit (not shown). An optical filter 105 is disposed in front of the image sensor 104. The first group barrel 111, the second group barrel 112, and the third group barrel 113 are holding members for the first group 101, the second group 102, and the third group 103, respectively. The first group barrel (first holding frame) 111 is provided with a lens barrier for lens protection and its driving unit, and the second group barrel (second holding frame) 112 is provided with a shutter mechanism and a diaphragm mechanism. However, detailed description thereof is omitted. The first group 101 and the second group 102 cooperate to mainly have a focal length adjustment function, and the third group 103 mainly has a focus adjustment function.

  A base 121 serving as a base of the lens barrel holds the image sensor 104 and is attached to a fixed cylinder 122 that is a support member. The fixed cylinder 122 has a cylindrical shape and has a cam groove 122a on the inner periphery. The lens barrel includes a first cam member (first group cam ring 124), a second cam member (second group cam ring 126), and a third cam member (moving cam ring 123). The first group cam ring 124 is cam-engaged and held with the first group barrel 111, and the second group cam ring 126 is cam-engaged with the second group barrel 112 and held. The moving cam ring 123 engages with and guides the first group cam ring 124 and the second group cam ring 126. Furthermore, a first restricting member (first group rectilinear ring 125), a second restricting member (second group rectilinear ring 127), and a rectilinear guide member (guide plate 128) for restricting rotation of the rectilinear ring are provided.

  The cylindrical moving cam ring 123 has a cam follower 123z on the outer periphery thereof, which engages with the cam groove 122a of the fixed cylinder 122. Two types of cam grooves 123a and 123b are formed on the inner periphery of the movable cam ring 123, and a cam follower (not shown) formed in the first group rectilinear ring 125 and the second group rectilinear ring 127 engages. That is, the cam follower provided on the outer periphery of the first group rectilinear ring 125 is engaged with the cam groove 123a, and the cam follower provided on the outer periphery of the second group rectilinear ring 127 is engaged with the cam groove 123b. The first group rectilinear ring 125 holds the first group cam ring 124, can move integrally with the first group cam ring 124 in the optical axis direction, and can relatively rotate in the direction around the optical axis. A cam groove 124 a is formed on the inner periphery of the first group cam ring 124, and a cam follower 111 z provided on the outer periphery of the first group barrel 111 is engaged. The second group rectilinear ring 127 holds the second group cam ring 126, can move integrally with the second group cam ring 126 in the optical axis direction, and can relatively rotate in the direction around the optical axis. A cam groove 126 a is formed on the inner periphery of the second group cam ring 126, and a cam follower 112 z provided on the outer periphery of the second group barrel 112 is engaged. The guide plate 128 is a rectilinear guide member whose rotation is restricted with respect to the fixed cylinder 122, and the first group rectilinear ring 125 and the second group rectilinear ring 127 of the first group rectilinear ring 127 are controlled by two keys (rectangular restricting portions in this example) described later. The rotation is restricted.

  This lens barrel is a three-stage barrel in which the positions of the first group barrel 111 and the second group barrel 112 in the optical axis direction are determined by three cam rings 123, 124, and 126, respectively. By the way, the optical system of this example is an optical system in which the first group 101 has a negative power, the second group 102 has a positive power, and the third group 103 has a positive power. And the arrangement of the two groups of lenses. The second group 102 has a property that the focal length is changed by largely moving in the optical axis direction. In recent years, the movement amount of the two groups with respect to the total length of the lens tends to be relatively large due to the shortening of the total length of the lens and the increase in magnification. In the past, the total retracted length of the lens barrel was determined by the amount of movement of one group, but in recent years, the influence of the amount of movement of the two groups has increased.

  FIG. 2 schematically shows the cam locus of each lens group for an optical system in which the first group is negative and the second group and the third group have positive powers. 2A shows the cam trajectory of the first group 101, and FIG. 2B shows the cam trajectory of the second group lens. The upper side of the drawing shows the subject side, that is, the front of the imaging apparatus. “Collapse” represents the state in which the lens barrel is housed in the camera body when it is not in operation, “Wide end” represents the wide-angle end for the change in the angle of view, and “Tele end” represents the telephoto end for the change in the angle of view. . L (122a) in FIG. 2 represents the cam locus of the cam groove 122a provided on the inner periphery of the fixed cylinder 122, changes linearly from the retracted side to the front of the wide end, and is a fixed position from the front of the wide end to the tele end. It becomes. In both the first group 101 and the second group 102, a stroke portion by the cam groove 122a and the cam follower 123z engaged therewith is added as a common component to the position in the optical axis direction. In FIG. 2A, L (123a) represents the cam locus of the cam groove 123a provided on the inner periphery of the movable cam ring 123, and linearly changes from the collapsed position to the front of the wide end, and from the front of the wide end to the tele end. It becomes a fixed position over. L (124a) is a cam locus of the cam groove 124a provided on the inner periphery of the first group cam ring 124, and linearly changes from the collapsed position to the front of the wide end, and downwards from the wide end to the tele end. Has a convex curve. The position of the first group 101 in the optical axis direction is determined by the sum of the position components of the cam loci indicated by L (122a), L (123a), and L (124a), as indicated by the combined trajectory L1total. Moves in the optical axis direction according to this locus.

  For the second group 102, L (123b) shown in FIG. 2B represents the cam trajectory of the cam groove 123b provided on the inner periphery of the movable cam ring 123, and is at a fixed position from the collapsed position to beyond the wide end. It has a straight line from the wide end to the tele end. L (126a) represents the cam locus of the cam groove 126a provided on the inner periphery of the second group cam ring 126, and has a straight portion with a negative gradient (retracting direction) from the collapsed position to the wide end, and a straight portion from the wide end to the tele end. It has. The combined trajectory L2total (a) represents the sum of the position components of the cam trajectories indicated by L (122a), L (123b), and L (126a), that is, the movement trajectory of the second group 102.

  In the figure, Δ12wide represents the interval (positional difference) between the first group 101 and the second group 102 at the wide end, and Δ12tele (a) represents the interval between the first group 101 and the second group 102 at the tele end. In this way, the same amount of movement from the retracted position is required for each lens group. The distance between the first group 101 and the second group 102 needs to be able to change greatly from Δ12wide at the wide end to Δ12tele (a) at the tele end. This is achieved by configuring the first group barrel 111 with a three-stage cam configuration and the second group barrel 112 with a three-stage cam configuration. For example, in a two-group cam configuration, a two-stage configuration without a cam locus L (123b) is assumed. In this case, the combined trajectory of the second group is L2total (b) indicated by a broken line, and the distance between the first group and the second group at the tele end is increased from Δ12tele (a) to Δ12tele (b), and the change in the field angle magnification is reduced. End up.

  In the present embodiment, the first-group cam groove 123a and the second-group cam groove 123b are separately formed in the second-stage moving cam ring 123 from the base 121. In other words, the mutual distance between the first group 101 and the second group 102 is equal to the stroke of two cams of the first group barrel 111 (= L (123a) + L (124a)) and the two cams of the second group barrel 112. It is determined by the difference in stroke (= L (123b) + L (126a)). Thereby, even in a lens barrel having a short retraction length, a large amount of change can be obtained with respect to the mutual distance between the first group and the second group, and a lens barrel suitable for thinning can be realized. For example, when the first and second group cams are separated from the base at the third stage, the mutual distance between the first group and the second group is determined only by the cam stroke for one stage, so this can be increased. It will disappear.

  Next, the configuration of the lens barrel will be described in detail. FIG. 3 is an exploded perspective view of the zoom mechanism system in the lens barrel. First, the holding mechanism of the first group 101 will be described. The first group rectilinear ring 125 is fitted to the inner periphery of the first group cam ring 124, and both of them can be moved and moved integrally in the optical axis direction by a drop-off restricting portion (not shown). And relatively rotatable. Three cam followers 111z provided in the first group barrel 111 are engaged with cam grooves 124a formed at three locations on the inner peripheral surface of the first group cam ring 124, so that the first group barrel 111 is cam groove 124a. Will be guided along. Straight guide grooves 125a are formed at three locations on the side surface of the cylindrical portion of the first group rectilinear ring 125, and each cam follower 111z provided in the first group barrel 111 engages to rotate the first group barrel 111. Be regulated. The rotation restriction of the first group rectilinear ring 125 itself is performed by fitting two keys 128a erected on the guide plate 128 into two slits 125b formed on the side surface of the first group rectilinear ring 125, respectively. Each key 128a is located opposite to each other across the optical axis and extends parallel to the optical axis. The guide plate 128 is formed with three convex portions 128z extending radially outward from the flange portion thereof, and these are fitted into straight guide grooves 122b formed at three locations on the inner periphery of the fixed cylinder 122, respectively. This restricts rotation.

  As for the holding mechanism of the second group barrel 112, similarly to the case of the first group barrel 111, the second group rectilinear ring 127 is fitted to the inner periphery of the second group cam ring 126. It can move integrally in the direction and can rotate relatively. Cam followers 112z formed at three locations on the second group barrel 112 are respectively engaged with cam grooves 126a formed at three locations on the inner periphery of the second group cam ring 126, and the second group barrel 112 is guided along the cam grooves 126a. Is done. Three rectilinear guide grooves 127a are formed on the side surface of the cylindrical portion of the second group rectilinear ring 127, and cam followers 112z formed in three places on the second group barrel 112 are fitted into the respective guide grooves 127a, so that the second group barrel The rotation of 112 is restricted. The second group rectilinear ring 127 is formed with a flange portion 127f extending outward in the radial direction from the cylindrical portion, and is formed with two slit holes 127b. By inserting each key 128a of the guide plate 128 into the slit hole 127b of the flange portion 127f, the rotation of the second group rectilinear ring 127 is restricted. The second group cam ring 126 is formed with a flange portion 126f extending outward from the cylindrical portion in the radial direction, and each key 128a is inserted into two arc-shaped holes 126c formed in this portion. Is done.

  Next, the engagement relationship between the cam groove and the cam follower will be described. The first cam follower 125 z formed on the first group straight ring 125 engages with a first cam groove 123 a formed on the inner periphery of the movable cam ring 123. A second cam follower 127 z formed on the second group rectilinear ring 127 engages with a second cam groove 123 b formed on the inner periphery of the movable cam ring 123. Thus, the first group rectilinear ring 125 and the second group rectilinear ring 127 are guided along the cam grooves 123a and 123b, respectively. Three rectilinear guide grooves 123c are formed on the inner periphery of the moving cam ring 123 in the circumferential direction. A projection 124z on the outer periphery of the first group cam ring 124 and a projection 126z on the outer periphery of the second group cam ring 126 are fitted into these linear guide grooves 123c, respectively, and the first group cam ring 124 and the second group cam ring 126 are fitted. Rotates following the moving cam ring 123. The moving cam ring 123 is guided along cam grooves 122 a formed at three locations on the inner periphery of the fixed cylinder 122. That is, each cam follower 123z engages with the corresponding cam groove 122a. A gear portion 123 g is integrally formed on the outer periphery of the moving cam ring 123. The force of the drive motor is transmitted to the gear portion via a drive gear, which will be described later, and the moving cam ring 123 rotates around the optical axis and moves in the optical axis direction. The guide plate 128 can be moved in the optical axis direction integrally with the moving cam ring 123 by a drop-off restricting portion (not shown) provided on the moving cam ring 123 and can be relatively rotated in the direction around the optical axis. .

  In this structure, the first group cam ring 124 also rotates following the rotation of the movable cam ring 123. However, since the first group rectilinear ring 125 is restricted in rotation by the key 128a of the guide plate 128, the first group lens barrel 111 is rotated. Moves only in the direction of the optical axis. The first group rectilinear ring 125 has a flange portion 125f extending in the radial direction at the rear end thereof, and has the effect of improving the strength of the lens barrel and improving the light shielding property as will be described later.

  On the other hand, the second group cam ring 126 also rotates following the rotation of the movable cam ring 123, but the rotation of the second group rectilinear ring 127 is restricted by the key 128 a of the guide plate 128, so It will move only in the axial direction. The second group cam ring 126 and the second group rectilinear ring 127 have flange portions 126f and 127f extending in the radial direction at the rear ends thereof, respectively, for improving the strength of the lens barrel and improving the light shielding property as will be described later. There is an effect.

  FIG. 4 is an exploded perspective view showing the periphery of the zoom mechanism drive system, focus drive system, and image sensor in the lens barrel. A zoom motor 401 is attached below the base 121 as a drive source of the zoom mechanism. A gear 402 is fixed to the rotation shaft of the zoom motor 401, and the transmission gear group 403 transmits the rotational force of the gear 402 to the gear portion 123 g of the moving cam ring 123. A photo interrupter 404 provided in the vicinity of the gear 402 detects the rotation direction and the rotation speed of the zoom motor 401. A photo interrupter 405 provided on the base 121 detects a reset position during zoom driving. Reset detection is performed by shielding a photo interrupter 405 by a light shielding rib (not shown) provided in the second group rectilinear ring 127.

  A sleeve 113 a extends from the third group lens barrel 113, and the sleeve 113 a is supported by the base 121 by holding the guide bar 407 by the holding portion 121 a of the base 121 with the guide bar 407 inserted through this portion. . As a result, the third group lens barrel 113 can advance and retract along the guide bar 407 in a direction parallel to the optical axis. One end of the one-sided spring 408 is hooked on a hook 113 h provided on a part of the third group barrel 113, and the other end is hooked on a hook 121 h provided on a holding portion 121 a of the base 121. The focus motor 410 as a drive source of the focus drive mechanism constitutes a feed screw mechanism that drives the third group barrel 113. The third group lens barrel 113 advances and retreats along the guide bar 407 in a direction parallel to the optical axis by the rotation shaft 410 a of the focus motor 410 as a feed screw and the feed nut 411 provided on the third group lens barrel 113. The third group barrel 113 is provided with a rib 113b. When the photo interrupter 412 provided on the base 121 is shielded from light, the reset position of the third group barrel 113 during focus driving is detected. The image sensor 104 is fixed to the holding plate 420 and attached to the base 121 using a plurality of screws 421. A dust-proof rubber member 422 is sandwiched between the holding plate 420 and the optical filter 105 (not shown).

FIG. 5 is a cross-sectional view showing the lens barrel in the wide end state on a cut surface including both keys 128a of the guide plate 128 and along the optical axis. Hereinafter, the effect of improving the light shielding property and strength by the lens barrel configuration will be described with reference to FIG.
A slight gap exists in the radial direction between the moving cam ring 123 and the first group cam ring 124. If light from a strong light source such as sunlight passes through this gap and reaches the inside of the lens barrel, the captured image may be affected. Therefore, a part of the first group rectilinear ring 125 is extended outward in the radial direction to form a flange portion 125f. By making the outer diameter of the flange portion 125f substantially equal to the inner diameter of the moving cam ring 123, it is possible to block light entering the inside. That is, when light passes through the gap between the outer periphery of the first group cam ring 124 and the inner periphery of the moving cam ring 123, the intensity of the intrusion light is attenuated by repeating surface reflection. Thereafter, when passing through the gap between the flange portion 125f and the inner peripheral surface of the moving cam ring 123, the surface reflection is further repeated, so that the damping effect is further increased. In the present embodiment, the flange portion 125f is formed in the first group rectilinear ring 125, but a similar flange portion may be formed in the first group cam ring 124 instead of or in combination with this. The flange portion extends in a direction perpendicular to the optical axis of the lens group and extends to the inner peripheral surface of the movable cam ring 123, and if this portion is configured so that the key 128a penetrates, a light attenuation effect is obtained. It is done.

  Similarly, the outer diameters of the flange portion 126 f of the second group cam ring 126 and the flange portion 127 f of the second group rectilinear ring 127 are substantially equal to the inner diameter of the movable cam ring 123. Thereby, the light attenuated as described above is further attenuated in the gap between the flange portions 126f and 127f and the inner peripheral surface of the movable cam ring 123. Since the guide plate 128 is attached to the rear end surface of the moving cam ring 123, the light attenuated as described above is finally shielded by the guide plate 128. As a result, external light is attenuated to such an extent that it does not affect the captured image.

By the way, when retracted, the second group cam ring 126 and the second group rectilinear ring 127 are housed inside the first group barrel 111, the first group cam ring 124 and the first group rectilinear ring 125 in the radial direction orthogonal to the optical axis. For this reason, even if there is external light entering from the gap between the first group barrel 111 and the first group rectilinear ring 125, it can be shielded by the flange portions 126f and 127f. In this example, a configuration is adopted in which the key 128a of the guide plate 128 is inserted through a slit hole 127b formed in the flange portion 127f and an arc-shaped hole 126c formed in the flange portion 126f. Thereby, since each flange part exists in the outer side of a radial direction rather than the key 128a, the effect of light shielding increases.
As described above, if a flange portion having an outer diameter substantially equal to the inner diameter of the movable cam ring 123 is provided and the linear key passes through the flange portion, a structure in which light hardly passes can be realized.

  The presence of the flange portion outside the key 128a also has an effect of increasing the degree of freedom in design layout. This is because the projection 126z of the second group cam ring 126 can be arranged at an arbitrary position on the entire circumference of the flange portion, and the position of the interlocking portion is restricted by providing the interlocking portion with the adjacent member on the flange portion. Disappear. FIG. 6 is a front view and a central sectional view showing the relationship between the second group cam ring 126, the second group rectilinear ring 127, and the guide plate 128 at the wide end. The rotation of the second group rectilinear ring 127 is restricted by inserting the key 128a into the slit hole 127b. In the second group cam ring 126, arc-shaped slit holes 126c are formed so as to face the center of the optical axis and avoid the key 128a. In the guide plate 128, each key 128a is located at two locations facing each other, so the slit hole 126c is also located at two locations facing each other. In the second group cam ring 126 that rotates following the movement cam ring 123, the positional relationship between the projections 126z formed at three locations in the circumferential direction and the slit holes 126c becomes irregular. For example, as shown in FIG. 6, the upper left protrusion 126z is located outside the slit hole 126c. If a simple shape without a shape portion outside the slit hole 126c is used, there is no need to arrange the protrusion 126z between the two slit holes 126c in the circumferential direction. When the flange portion is provided outside the key 128a, such a restriction is not imposed. In the present embodiment, the protrusions 126z are provided at three locations along the circumferential direction around the optical axis, because the degree of freedom in design layout is taken into consideration. In other words, the protrusion 126z fits into the rectilinear groove 123c (see FIG. 3) formed on the inner periphery of the movable cam ring 123 as described above, but there are two types of cam grooves 123a and 123b in the circumferential direction on the inner periphery. Three places are formed over each. In order to avoid the cam grooves and arrange the rectilinear grooves 123c, it is desirable to dispose the rectilinear grooves 123c at three locations in the circumferential direction. Thus, by leaving the shape portion outside the slit hole 126c of the second group cam ring 126, an effect of increasing the degree of freedom of the design layout can be obtained. The above description also applies to the case where a flange portion is formed on the first group cam ring 124 and the projection 124z is disposed on the outer periphery.

  Next, the effect of improving the barrel strength by the flange will be described with reference to FIG. FIG. 7A is a diagram schematically showing a cross-sectional shape of the moving cam ring 123 and the first group rectilinear ring 125 cut along a plane passing through the cam follower 125z. In a normal use state, as shown in FIG. 7A, the cam follower 125z is securely fitted to the cam groove 123a. FIG. 7B exaggeratedly shows a situation in which an excessive external force is applied to the lens barrel tip from the front, such as when the camera falls and collides with the ground from the lens barrel tip. The cam follower 125z and the cam groove 123a have a tapered contact surface as shown in the cross section of FIG. 1 and have a gradient with respect to the optical axis direction, so that both of them try to slide with each other along the gradient by an external force from the front. . As shown in FIG. 7B, the portion of the moving cam ring 123 that is fitted to the cam follower 125z is temporarily deformed and bulges outward (see arrow F). In the first group straight ring 125, the cam follower 125z. Is deformed and bent inward (see arrow G). Arrows F and G indicate the direction of deformation. When this deformation is large, the cam follower 125z drops off from the cam groove 123a, and there is a possibility that the lens barrel cannot be normally operated thereafter. Therefore, in the present embodiment, a flange portion 125f is provided in the first group rectilinear ring 125, thereby adopting a shape that increases rigidity and is difficult to deform compared to a simple cylindrical shape. Further, as shown in FIG. 7B, in the first group rectilinear ring 125, the cam follower 125z bends inward, and at the same time, a portion located between the cam followers 125z swells outward. When the flange portion 125f bulging outward contacts the inner peripheral surface of the movable cam ring 123, further deformation is suppressed. Therefore, it is possible to obtain an effect that the cam follower 125z is not easily dropped from the cam groove 123a.

Further, as described above, the second group cam ring 126 and the second group rectilinear ring 127 are engaged with the moving cam ring 123, and the flanges 126f and 127f are bent to the inner side of the moving cam ring 123. Abuts the surface. As a result, the deformation of the movable cam ring 123 is suppressed, and the first-group rectilinear ring 125 is difficult to drop off.
Further, as described above, the guide plate 128 restricts both the first group rectilinear ring 125 and the second group rectilinear ring 127 with a common key 128a. Therefore, the effect of reducing the positional deviation in the rotation direction of the first group rectilinear ring 125 and the second group rectilinear ring 127 can be obtained. Also, it is no longer necessary to use two types of keys (regulators) for the first group regulation and the second group regulation as in the prior art, and the number of keys is reduced, which improves part workability and reduces costs. An effect is obtained. When the keys are used for each group, it is disadvantageous to ensure the operation accuracy. Therefore, as in this embodiment, it is effective to use one type of key for regulating both groups.

101 First lens group 102 Second lens group 104 Image sensor 123 Third cam member (moving cam ring)
124 1st cam member (1 group cam ring)
125 1st regulating member (group 1 straight ring)
125f Flange portion 126 Second cam member (second group cam ring)
126f Flange part 127 2nd regulating member (2nd group rectilinear ring)
127f Flange portion 128 Linear guide member 128a Restricting portion

Claims (6)

A lens barrel having a first lens group and a second lens group movable in an optical axis direction,
A first cam member that holds the first cam engages said first holding member of the holding member of the first lens group, movable the the first cam member integrally with the optical axis second for holding the first regulating member and the second lens group of the second cam engagement with the second holding member in the holding member for restricting the rotation of the first holding member comprising a The second cam member, a second restricting member which is movable in the optical axis direction integrally with the second cam member and restricts the rotation of the second holding member, the first cam member and the second cam member A third cam member for guiding the two cam members;
The first restricting member is formed with a first flange portion extending in a direction perpendicular to the optical axis of the first lens group and extending to the inner peripheral surface of the third cam member,
The second restricting member is formed with a second flange portion extending in a direction perpendicular to the optical axis of the second lens group and extending to the inner peripheral surface of the third cam member,
The lens mirror, wherein the first flange portion is cam-engaged with the third cam member, and the second flange portion is cam-engaged with the third cam member. Tube. And a linear guide member having a restricting portion that is movable in the optical axis direction integrally with the third cam member and restricts rotation of the first restricting member and the second restricting member. The lens barrel according to claim 1 . The lens barrel according to claim 2 , wherein the restricting portion passes through the first flange portion and the second flange portion . A lens barrel having a first lens group and a second lens group movable in an optical axis direction,
A first cam member that cam-engages with the first holding member of the first lens group and holds the first holding member;
A first regulating member for regulating the rotation of said first holding member,
A second cam member for holding the second holding member cam engaged with the second holding member of the second lens group,
A second restricting member for restricting rotation of the second holding member;
A third cam member for guiding the first and second cam members;
A linear guide member that is movable in the optical axis direction integrally with the third cam member and has a restricting portion that restricts rotation of the first restricting member;
The first cam member or the first regulating member has a first flange extending in a direction perpendicular to the optical axis of the first lens group and extending to the inner peripheral surface of the third cam member. A portion is formed, the restricting portion penetrates the first flange portion, and the second cam member extends in a direction perpendicular to the optical axis of the second lens group, and the third cam member A second flange portion extending to the inner peripheral surface of the cam member is formed, and the restricting portion passes through the second flange portion;
A protrusion for rotating by rotating with the third cam member is disposed on the outer periphery of the second flange portion, and a guide groove for engaging with the protrusion is formed on the third cam member. A lens barrel characterized by that. Said second cam member and the second regulating member, wherein the collapsed state of the lens barrel first holding member, relative to said first cam member and the first regulating member, perpendicular to the optical axis The lens barrel according to any one of claims 1 to 4, wherein the lens barrel is housed inside in a radial direction. The lens barrel according to any one of claims 1 to 5,
Imaging device being characterized in that an imaging device for converting a subject image imaged through the lens barrel to an electrical signal.

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