JP2007232889A - Lens barrel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens barrel capable of restraining backlash during the operation of moving a lens, and having a simple structure. <P>SOLUTION: The lens barrel has a lens hold member 2 for holding a lens 3, having a bearing 9 for receiving a guide shaft 8, and moved in the direction of an optical axis L by being guided along the guide shaft 8. The lens barrel includes a pressing member (spring 11) between the guide shaft 8 and lens hold member 2. In this case, the pressing direction of the plate spring 11 is the direction toward the center of the guide shaft 8a. In addition, it is preferable that the number of parts where the guide shaft 8a and bearing 9A are pressed by the plate spring 11 be more than one and they be separated in the direction of the optical axis. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lens barrel.

  A lens barrel, particularly a zoom lens barrel, is required to be smooth during an operation of moving the lens, such as a zooming operation that varies the focal length. The reason for this is that if the zooming operation is rattled, there is an adverse effect such as blurring of the captured image when shooting a movie. This is because various parts of the lens barrel may be worn out and the zooming mechanism or the like may not function.

  Therefore, during a zooming operation in which the lens moves in the optical axis direction, a fitting hole provided in a member that holds the lens, and a guide shaft that is inserted through the fitting hole and is installed parallel to the optical axis direction There has been proposed a technique for stabilizing the sliding (see Patent Document 1). The technology attaches a mechanism for applying a force in a fixed direction perpendicular to the optical axis direction to a member holding the lens, and attaches the fitting hole and the guide shaft by the force. This technology keeps the sliding position stable.

JP 2004-94172 A

  In the case of the technique of Patent Document 1, a configuration in which the force of the urging means is applied to the rack portion that is located at a position different from the sleeve portion that engages with the guide bar serving as the guide shaft, and is transmitted to the guide bar, that is, Since the transmission path of the urging force has a complicated configuration, the structure of the entire lens barrel is complicated.

  Therefore, the problem to be solved by the invention is to provide a lens barrel that can suppress rattling during the operation of moving the lens and has a simple structure.

  In order to solve the above-described problem, a lens barrel of the present invention includes a lens holding member that holds a lens and has a bearing that receives a guide shaft, and that is guided by the guide shaft and moves in the optical axis direction. A biasing member is provided between the guide shaft and the lens holding member.

  According to the present invention, the biasing member is slid in an oblique direction with respect to the guide shaft when the bearing of the lens holding member slides along the guide shaft (an operation to move the lens). It is made to slide along the guide shaft by the urging force. Therefore, for example, rattling that occurs due to the lens holding member sliding in the oblique direction to the guide shaft can be suppressed. Further, according to the present invention, since the urging member is provided between the guide shaft responsible for the movement of the lens and the lens holding member, the urging force transmission path becomes complicated as in the conventional patent document 1. Without complicating the structure of the entire lens barrel.

  In order to solve the above-described problem, the lens barrel of the present invention includes a lens holding member that holds a lens and has a bearing that receives a guide shaft, and that is guided by the guide shaft and moves in the optical axis direction. In the lens barrel provided, an urging member is provided between the guide shaft and the lens holding member, and the urging direction by the urging member is a direction toward the center of the guide shaft.

  According to the present invention, the urging member is provided between the guide shaft and the lens holding member as in the above-described invention, and the urging direction by the urging member is the direction toward the center of the guide shaft. The backlash between the bearing of the member and the guide shaft can be suppressed, and the structure of the entire lens barrel is not complicated.

  In order to solve the above-described problem, the lens barrel of the present invention includes a lens holding member that holds a lens, has a bearing that receives a guide shaft, and moves in the optical axis direction while being guided by the guide shaft. In the lens barrel, the bearing and / or the guide shaft has a biasing member for increasing the sliding frictional force between the bearing and the guide shaft, and the portion where the guide shaft and the lens holding member are in contact with each other by the biasing member is defined as the optical axis. Multiple locations separated in the direction.

  According to this invention, since the urging member is provided between the guide shaft and the lens holding member as in the above-described invention, rattling between the bearing of the lens holding member and the guide shaft can be suppressed. In addition, the entire structure of the lens barrel is not complicated. Furthermore, by providing a place where the guide shaft and the bearing come into contact with each other by the urging member at a plurality of locations separated in the optical axis direction, the guide shaft around it is like a seesaw with one place where the urging member is installed as a fulcrum. When trying to move, the movement of the seesaw is suppressed at a position away from the fulcrum in the optical axis direction. As a result, rattling between the bearing and the guide shaft due to the movement of the seesaw can be suppressed.

  In order to solve the above-described problem, the lens barrel of the present invention has a bearing that holds the lens and has an insertion portion through which the guide shaft is inserted. The lens barrel is guided by the guide shaft and moves in the optical axis direction. And a biasing member is provided between the guide shaft and the lens holding member, and the biasing force of the biasing member is applied to the insertion portion in a state where the guide shaft and the bearing are in contact with each other by the biasing member. The giving side is provided with a larger gap than the side receiving the biasing force.

  According to this invention, since the urging member is provided between the guide shaft and the lens holding member as in the above-described invention, rattling between the bearing of the lens holding member and the guide shaft can be suppressed. In addition, the entire structure of the lens barrel is not complicated. Further, when the guide shaft is inserted into the insertion portion and the guide shaft and the bearing are in contact with each other by the urging member, there is a large gap in the insertion portion, so that dust generated in the lens barrel is in the insertion portion. Even if it enters, it can be easily discharged, and the dust can be prevented from hindering smooth sliding between the bearing and the guide shaft.

  In order to solve the above-described problems, the lens barrel of the present invention has a bearing that holds a lens and receives a circular cylindrical guide shaft extending in the optical axis direction of the lens, and is guided by the guide shaft. A lens holding member that moves in the direction of the optical axis, and an urging member is provided between the guide shaft and the lens holding member. Further, the contact portion between the urging member and the guide shaft is defined as one portion along the outer periphery of the guide shaft, and the guide shaft is supported at three points by the contact portion.

  According to this invention, since the urging member is provided between the guide shaft and the lens holding member as in the above-described invention, rattling between the bearing of the lens holding member and the guide shaft can be suppressed. In addition, the entire structure of the lens barrel is not complicated. Further, the contact portion between the cylindrical guide shaft having a circular cross section and the lens holding member by the biasing member is set at two locations along the outer periphery of the guide shaft, and the contact portion between the biasing member and the guide shaft is By supporting the guide shaft at three points along the outer periphery of the guide shaft and supporting the guide shaft at three points, the guide shaft can be stabilized in a direction perpendicular to the optical axis direction, and further has a backlash suppressing effect. Obtainable.

  In another invention, in addition to the above-described invention, the urging member is an elastic body integrated with the lens holding member. An elastic body such as a spring and rubber suitably functions as an urging member.

  In another invention, in addition to the above-described invention, the urging member is a leaf spring, and the leaf spring is disposed on the opposite side of the lens with the guide shaft interposed therebetween. By using a leaf spring as the urging member, the handleability of the urging member is improved, and the lens barrel can be easily manufactured. In addition, since the leaf spring is disposed on the opposite side of the lens across the guide shaft, there is no leaf spring in the region where the lens performs its function, so that the effective area of the lens is ensured to the maximum. be able to.

  The lens barrel of the present invention can suppress rattling during the operation of moving the lens and has a simple structure.

  The lens barrel 1 according to the first embodiment of the present invention will be described below with reference to FIG. FIG. 1A is a cross-sectional view of the main part of the lens barrel 1 according to the first embodiment, and FIG. 1B is a cross-sectional view taken along line AA in FIG.

  The lens barrel 1 according to the first embodiment mainly includes a lens barrel body 7, a lens holding member 2, a lens 3, a guide shaft 8a, and a shaft 12. The lens barrel 1 is surrounded by a lens barrel body 7 that protects the lens 3. Hereinafter, in this specification, the lens barrel including the lens barrel main body 7 is referred to as a lens barrel. The lens holding member 2 is accommodated in the cylindrical lens barrel body 7 while holding the lens 3 and being supported by the guide shaft 8 a and the shaft 12. Here, the lens holding member 2 is a frame 4 that holds the lens 3, and a first arm 5a that extends outside the frame 4 in a direction perpendicular to the optical axis L and toward the guide shaft 8a. And a second arm 5b extending in a direction opposite to the first arm 5a and in the direction toward the shaft 12, a bearing support portion 9a disposed at the tip of the first arm 5a and extending in the optical axis L direction, and a bearing It has two bearing cylindrical parts 9b arrange | positioned at the both ends of the support part 9a, and the U-shaped groove 6 in the front-end | tip of the 2nd arm 5b. A bearing 9A is constituted by the bearing cylindrical portion 9b and the bearing support portion 9a. The length of the bearing 9A in the optical axis L direction is 6 mm.

  In the frame 4, two lenses constituting the lens 3 are fitted and fixed and held so that the optical axis L is at the center position. Inside the cylindrical barrel body 7, a guide shaft 8a and a shaft 12 are disposed and fixed in parallel with the optical axis L direction. The columnar guide shaft 8a is disposed and fixed to the lens barrel body 7 so that the maximum distance between the front end and the rear end when the bearing 9A slides in the optical axis direction is 40 mm. That is, the distance between the front end position of the bearing 9A when the lens holding member 2 is moved downward in FIG. 1A and the rear end position of the bearing 9A when moved upward is 40 mm. Yes. The guide shaft 8a is inserted through both of the insertion holes 14 provided in the two bearing tubular portions 9b. As shown in FIG. 1 (B), the insertion hole 14 has a quadrangular shape on the side away from the optical axis L, a triangular shape on the side close to the optical axis L, and a pentagon in which the square and the triangle communicate with each other. The cylindrical shaft 12 engages with the U-shaped groove 6 and prevents the bearing 9A from rotating about the guide shaft 8a. Further, a spring locking hole 15 into which a leaf spring 11 described later is inserted is provided adjacent to the insertion hole 14. Here, since the bearing 9 </ b> A and the lens 3 are integrated, the bearing 9 </ b> A holds the lens 3.

  Further, in the insertion hole 14 of the bearing cylindrical portion 9b, there is a groove (V-shaped groove 10) having a V-shaped cross section as a part of the pentagonal insertion hole 14 described above. These two wall surfaces are in contact with the side surfaces of cylindrical guide shafts 8a each having a circular cross section. And the guide shaft 8a is urged | biased by the leaf | plate spring 11 as an urging | biasing member to the two inner side surfaces (a total of four side surfaces at both ends) of the V-shaped groove 10. FIG. The leaf spring 11 includes a curved portion 11a whose middle portion is curved in a U-shape, two planar portions 11b folded back on the opposite side of the curved portion 11a, and an optical axis further on the distal end side of the planar portion 11b. L has a locking portion 11c extended in a direction perpendicular to the optical axis L and away from the optical axis L. Both ends of the leaf spring 11 are inserted into the spring locking holes 15, and the locking portions 11 c come into contact with the outer surfaces of the bearing cylindrical portions 9 b, thereby being engaged and fixed to the bearing cylindrical portions 9 b. At this time, the U-shaped curved portion 11a abuts against the side surface of the guide shaft 8a, and urges the guide shaft 8a in the optical axis L direction. Although the sliding friction coefficient between the leaf spring 11 and the guide shaft 8a is set to 0.5, it may be within ± 20% of this value or other values.

  In the leaf spring 11, the guide shaft 8a in the insertion hole 14 of the bearing cylindrical portion 9b is always in contact with the wall surfaces of the V-shaped grooves 10 at both ends during a zooming operation in which the lens 3 moves in the optical axis L direction. Energizing force to touch. As a result, the bearing 9A is prevented from being inclined with respect to the guide shaft 8a. Therefore, rattling when the lens 3 is moved in the optical axis L direction can be suppressed. The biasing force generating mechanism here does not complicate the biasing force transmission path, and the bearing 9A slides directly along the guide shaft 8a. Therefore, the sliding frictional force between the bearing 9A and the guide shaft 8a is increased, but this sliding friction is kept low, and the lens holding member 2 moves smoothly in the direction of the optical axis L. The urging direction of the leaf spring 11 is a direction toward the center of the guide shaft 8a.

  Further, in the state where the guide shaft 8a and the bearing 9A are in contact with each other by the urging force of the leaf spring 11, a large gap 14a is generated in the insertion hole 14 of the bearing cylindrical portion 9b on the side far from the optical axis L. To do. The gap 14a may not have the leaf spring 11 in the insertion hole 14 having a pentagonal cross section, and is a gap 14a larger than the gap 14b on the opposite side. For this reason, even if dust enters the gap 14a, the dust does not stay in the insertion hole 14 and is easily discharged. When dust enters between the bearing 9A and the guide shaft 8a and stays there, smooth sliding of the lens holding member 2 is prevented, but this embodiment has an effect of suppressing the problem. Further, since the insertion hole 14 has a gap 14b at the bottom of the V-shaped groove 10, the effect is greater.

  Here, the guide shaft 8a has a circular column shape with a circular cross section, and portions separated by 120 degrees along the outer periphery thereof are in contact with the two inner surfaces of the V-shaped groove 10, respectively. Further, the leaf spring 11 is in contact with a position 180 degrees away from the intermediate position along the outer periphery of the guide shaft 8a at the two contact points along the outer periphery of the guide shaft 8a. Therefore, the guide shaft 8a is supported at three points in the direction orthogonal to the optical axis L direction by the two inner surfaces of the V-shaped groove 10 and the leaf spring 11, so that it is orthogonal to the optical axis L direction. It is possible to sufficiently counteract unintentionally applied forces on the guide shaft 8a from all directions. As a result, rattling during the operation of moving the lens holding member 2 is further suppressed. The location of the guide shaft 8a contacting the inner surface of the V-shaped groove 10 may be other angles such as 90 degrees instead of 120 degrees. Even in that case, it is preferable that the leaf spring 11 is brought into contact at a position 180 degrees away from an intermediate position between the two contact points. The V-shaped groove 10 is formed only in the bearing cylindrical portion 9b, but may be formed over the entire optical axis direction of the bearing 9A.

  Next, a lens barrel 1A according to the second embodiment will be described with reference to FIG. FIG. 2A shows a cross-sectional view of a main part of a lens barrel 1A according to the second embodiment, and FIG. 2B shows a cross-sectional view taken along line AA in FIG. The lens barrel 1A according to the second embodiment is the same as the lens barrel 1 according to the first embodiment described above, except for the shape and structure of the bearing 9B and the biasing means. Therefore, the same reference numerals are given to the same members as those in the lens barrel 1 of the first embodiment, and the description thereof is omitted or simplified.

  The urging means of the lens barrel 1A according to the second embodiment includes a leaf spring 21. As shown in FIG. 2A, the leaf spring 21 is formed in a W shape as viewed from the side, and when the bulge portion of the intermediate portion (leaf spring intermediate portion 21a) is pushed, the bulge The leaf spring opposite end portions 21b swelled on the opposite side of the spring strongly abut against the guide shaft 8a. The cylindrical bearing 9B has a length that allows both ends of the bearing 9B in the optical axis L direction to be engaged with the locking portions 21c of the leaf spring both ends 21 (a length slightly exceeding 6 mm). The plate spring 21 and the guide shaft 8a have a pentagonal section insertion hole 14 into which the leaf spring 21 and the guide shaft 8a can be inserted. Unlike the first embodiment, the insertion hole 14 here is formed over the entire length direction (optical axis L direction) of the bearing 9B.

  The plate spring 21 is installed and fixed by engaging both ends of the bearing 9B in the optical axis L direction with the engaging portions 21c of the plate spring both ends 21b. Here, the maximum length (6 mm) of the contact portion between the bearing 9B and the guide shaft 8a is the maximum distance between the front end and the rear end when the bearing 9B slides in the optical axis L direction. (40 mm) or less. Therefore, a sufficient moving distance of the lens 3 can be secured. The leaf spring 21 is installed between the guide shaft 8a and the bearing 9B on the side opposite to the lens 3 with the guide shaft 8a interposed therebetween. Therefore, the leaf spring 21 does not exist in the region where the lens 3 performs its function, and the effective area of the lens 3 can be ensured to the maximum.

  In the installed state of the leaf spring 21, the guide shaft 8a, and the bearing 9B in FIG. 2, the inner wall surface of the insertion hole 14 of the bearing 9B presses the bulging portion of the leaf spring intermediate portion 21a, and the pressing force is applied to both ends of the leaf spring. It is transmitted to the bulging part of the part 21b. Then, the bulging portions of the leaf spring both ends 21b that have received the pressing force abut against the guide shaft 8a at a distance of 6 mm in the optical axis L direction. Therefore, the lens holding member 2 slides stably along the guide shaft 8a. Further, the leaf spring 21 increases the sliding frictional force of the lens holding member 2 with respect to the guide shaft 8a. This frictional force is set to 0.5 or other values as in the first embodiment. Since the lens holding member 2 is not so large that the movement of the lens holding member 2 is stopped, the lens holding member 2 moves smoothly without stopping. The urging force by the leaf spring 21 is in the direction toward the center of the guide shaft 8a.

  Further, in a state where the guide shaft 8a and the bearing 9B are in contact with each other by the urging force of the leaf spring 21, a sufficiently large gap 14a is generated in the insertion hole 14 on the side where the leaf spring 21 is disposed. Since the leaf spring 21 and the guide shaft 8a are disposed in the insertion hole 14 having a pentagonal cross section, and the leaf spring 21 is disposed in the insertion hole 14 so as to be bent in a W shape, there is a gap. 14a is made considerably larger than the gap 14b on the opposite side. For this reason, similarly to the lens barrel 1 according to the first embodiment described above, even if dust enters the large gap 14a in the insertion hole 14, it can be easily discharged, and the dust is separated from the bearing 9B. There is an effect that the smooth sliding with the guide shaft 8a can be suppressed. Further, since the insertion hole 14 has a gap 14b at the bottom portion of the V-shaped groove 10, the effect is greater.

  By pressing the guide shaft 8a at a position 6 mm away in the direction of the optical axis L by the two bulging portions of the leaf spring both ends 21b, the guide shaft 8a around the guide shaft 8a is like a seesaw with one of the pressed positions as a fulcrum. Even if it tries to move, it acts to suppress the movement like the seesaw with the pressing force of the other pressing position. Here, the fact that the position of the pressing part (contact part) is 6 mm away in the optical axis L direction makes the action of suppressing movement like a seesaw more effective. As a result, rattling between the bearing 9B and the guide shaft 8a can be further suppressed. Further, when the contact area is increased by this configuration, the sliding frictional force per unit area is reduced, and the bearing 9B and the guide shaft 8a slide more smoothly.

  Next, a lens barrel 1B according to a third embodiment will be described with reference to FIG. FIG. 3A shows a cross-sectional view of a main part of a lens barrel 1B according to the third embodiment, and FIG. 3B shows a cross-sectional view taken along line AA in FIG. The lens barrel 1B according to the third embodiment is the same as the lens barrel 1 according to the first embodiment described above, except for the shape and structure of the bearing 9C and the biasing means. Therefore, the same reference numerals are given to the same members as those in the lens barrel 1 of the first embodiment, and the description thereof is omitted or simplified.

  The urging means of the lens barrel 1B according to the third embodiment includes a coil spring 31, a spring retainer 32, and a protrusion 33. The coil spring 31 is disposed between the guide shaft 8a and the bearing 9C on the side opposite to the lens 3 with the guide shaft 8a interposed therebetween. The coil spring 31 receives the pressing force of the spring presser 32 and transmits the pressing force to the protrusion 33. Then, the slightly pointed circular tip of the projection 33 made of a resin molding or the like that has received the pressing force is biased in a direction toward the center of the guide shaft 8a. The spring retainer 32 has a male screw that engages with a female screw formed on the bearing 9 </ b> C, and a pressing force is applied to the coil spring 31 by tightening the screw. Similarly to the lens barrel 1A according to the second embodiment described above, the coil spring 31 biases the guide shaft 8a at two positions separated by 6 mm in the optical axis direction. Therefore, similarly to the lens barrel 1A according to the second embodiment, it is possible to further suppress the play between the bearing 9C and the guide shaft 8a. Here, the bearing 9C is composed of a bearing cylindrical portion 9d and a bearing support portion 9c. The protrusion 33 includes a through-hole opened along a direction perpendicular to the optical axis L provided in the bearing cylindrical portion 9d, that is, a space in which the spring retainer 32 is disposed, the insertion hole 14 and the insertion hole 14. The rear end (the opposite side to the guide shaft 8a) is disposed in the through hole connecting the two. A coil spring 31 is disposed in the through hole. Therefore, the coil spring 31 is guided so that the expansion / contraction direction is the optical axis L direction, and the protrusion 33 moves in the through hole, so that the pressing force of the spring retainer 32 and the coil spring 31 is increased. Is transmitted to the guide shaft 8a so as not to be directed in directions other than the optical axis L direction.

  Further, in a state where the guide shaft 8a and the bearing 9C are in contact with each other by the urging force of the coil spring 31, a sufficiently large gap 14a is generated in the insertion hole 14 on the side where the coil spring 31 is disposed. A projection 33 is disposed in the insertion hole 14 having a pentagonal cross section, and the guide shaft 8a is urged toward the lens 3 by the projection 33, so that a large gap 14a is obtained. For this reason, similarly to the lens barrel 1 according to the first embodiment described above, even if dust enters the large gap 14a in the insertion hole 14, it can be easily discharged, and the dust is separated from the bearing 9C. There is an effect that the smooth sliding with the guide shaft 8a can be suppressed. Further, since the insertion hole 14 has a gap 14b at the bottom of the V-shaped groove 10, the effect is greater.

  Hereinafter, a lens barrel 1C according to the fourth embodiment will be described with reference to FIG. FIG. 4A shows a cross-sectional view of a main part of a lens barrel 1C according to the fourth embodiment, and FIG. 4B shows a cross-sectional view taken along line AA in FIG. The lens barrel 1C according to the fourth embodiment is the same as the lens barrel 1B according to the above-described third embodiment, except for the shape of the bearing 9D and the biasing means / structure. Therefore, the same members as those in the lens barrel 1B of the third embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  The biasing means of the lens barrel 1C according to the fourth embodiment includes a coil spring 31, a spring presser 32, and a pressing member 41. The coil spring 31 is installed on the opposite side of the lens 3 between the guide shaft 8a and the bearing 9D with the guide shaft 8a interposed therebetween. The coil spring 31 receives the pressing force of the spring presser 32 and transmits the pressing force to the pressing member 41. The pressing member 41 that has received the pressing force biases the direction toward the center of the guide shaft 8a. The spring retainer 32 has a male screw that engages with a female screw formed on the bearing 9 </ b> D, and a pressing force is applied to the coil spring 31 by tightening the screw. The coil spring 31 urges the guide shaft 8a at two positions 6 mm away in the optical axis L direction, similarly to the lens barrel 1B according to the third embodiment described above. Therefore, similarly to the lens barrel 1B according to the third embodiment, it is possible to further suppress the play between the bearing 9D and the guide shaft 8a. Here, the bearing 9D is composed of a bearing cylindrical portion 9f, a bearing support portion 9e, and a pressing member guide 9g.

  The pressing member 41 of the lens barrel 1C according to the fourth embodiment has a cylindrical shape as a whole, and has a cylindrical concave portion into which the coil spring 31 is inserted on the spring retainer 32 side, and a guide shaft on the guide shaft 8a side. It has a V-shaped groove with which the peripheral surface of 8a abuts. With this configuration, the coil spring 31 biases the pressing member 41 in the direction in which the side surface of the guide shaft 8 a is fitted into the V-shaped groove of the pressing member 41. As a result, the bearing 9D slides smoothly along the guide shaft 8a. In addition, this configuration increases the contact area between the guide shaft 8a and the bearing 9D, but the sliding friction force per unit area decreases, and the lens holding member 2 can be moved more smoothly in the direction of the optical axis L. It has an effect that can be done. The pressing member 41 transmits the pressing force by the spring pressing 32 and the coil spring 31 so that the pressing force by the spring pressing 32 and the coil spring 31 is not directed in the direction other than the optical axis L direction by the pressing member guide 9g of the bearing tubular portion 9f.

  The lens barrels 1, 1 </ b> A, 1 </ b> B, and 1 </ b> C according to each embodiment have been described above, but various modifications can be made without changing the gist of the present invention. For example, a protective material that increases slidability and prevents wear may be provided on the surface of the urging member that contacts the guide shaft 8a. The reason is that it is possible to suppress the urging member from being worn by repeated sliding with the guide shaft 8a. For example, in the lens barrels 1 and 1A according to the first and second embodiments, since the leaf spring 11 is used as the biasing member, the surface of the leaf spring 11 is used as a protective material by utilizing a molding technique or the like. It is preferable to form a resin layer.

  In the lens barrels 1A, 1B, and 1C according to the second, third, and fourth embodiments, the places where the guide shaft 8a is pressed by the biasing member are two places that are separated in the optical axis L direction. However, it has bearings 9B, 9C, and 9D for holding the lens 3 and receiving the guide shaft 8a, and includes a lens holding member 2 that is guided by the guide shaft 8a and moves in the optical axis L direction. In the lens barrel in which the urging member is provided between the holding member 2, the location where the guide shaft 8 a is pressed by the urging member can be a location exceeding 2 away in the optical axis L direction. If the number of locations where the biasing member makes contact between the guide shaft 8a and the bearing 9 and the location where the biasing member side and the guide shaft 8a contact each other increases, the sliding frictional force per unit area at each contact location. The lens 3 can be moved more smoothly in the direction of the optical axis L.

  In the lens barrels 1, 1B, and 1C according to the first, third, and fourth embodiments, the V-shaped groove 10 is provided at only two locations on both ends of the bearings 9A, 9C, and 9D. , 9C, 9D may extend over the entire optical axis L direction. Furthermore, in the lens barrel 1A according to the second embodiment, the V-shaped groove 10 extends over the entire optical axis L direction of the bearing 9B, but only in a part (preferably both ends). The V-shaped groove 10 may be formed.

  Further, in the lens barrels 1A, 1B, and 1C according to the second, third, and fourth embodiments, the locations where the guide shaft 8a is pressed by the urging member are two locations separated in the optical axis direction. However, if the suppression effect is sufficiently obtained by the rattling suppression means, in the lens barrels 1A, 1B, and 1C according to the second, third, and fourth embodiments, the guide shaft 8a is pressed by the urging member. One place can be made into one place. Further, although the direction of the force acting between the guide shaft 8a and the lens holding member 2 by the urging member is the direction orthogonal to the optical axis L, the force does not necessarily have to act in this direction.

  When the location where the guide shaft 8a is pressed by the biasing member is a plurality of locations separated in the optical axis L direction, the biasing force at each contact location (pressing location) may not be equal. The reason for this is that even if the guide shaft 8a around it moves like a seesaw with one contact position (pressing point) as a fulcrum, movement like the seesaw can be suppressed at other contact positions. This is because if the biasing force has a certain degree, it is possible to obtain an effect of suppressing the play between the lens holding member 2 and the guide shaft 8a.

  In the lens barrels 1A, 1B, and 1C according to the second, third, and fourth embodiments, the place where the guide shaft 8a is pressed by the urging member is two places that are separated by 6 mm in the optical axis direction. In the lens barrel 1 according to the first embodiment, the length of the bearing 9A in the optical axis L direction is 6 mm, and the contact portion between the guide shaft 8a and the lens holding member 2 is the farthest distance. The interval was 6 to 6 mm. Further, the contact distance between the leaf spring 11 and the guide shaft 8a is set to one place at the center of the interval of 3 to 4 mm. These 6 mm are sufficient to suppress the movement of the seesaw at the other abutting position even if the surrounding guide shaft 8a tries to move like a seesaw with the one abutting position to be pressed as a fulcrum. It has significance as a distance. If it has the same significance, a larger distance is preferable. If the distance can be secured by 15 mm or more, even if no biasing member is provided between the guide shaft 8a and the lens holding member 2, if the gap between them is about 15 μm, the bearing and the guide shaft 8a are somewhat fixed. It is possible to suppress rattling. However, in order to meet the recent demand for downsizing of the lens barrel, the distance cannot be increased to 15 mm. Therefore, by providing a biasing member between the guide shaft 8a and the lens holding member 2, the lens barrels 1, 1A, 1B, and 1C according to the first, second, third, and fourth embodiments are provided. As described above, even when the distance is reduced to 6 mm, the rattling between the lens holding member 2 and the guide shaft 8a can be suppressed.

  In the lens barrels 1, 1A, 1B, and 1C according to the first, second, third, and fourth embodiments, the bearings 9A, 9B. By providing the V-shaped groove 10 in the insertion holes 14 of 9C and 9D, two points for realizing stable three-point support are secured. Here, in order to secure the two points, the groove shape is not limited to the V shape. For example, two points can be secured by providing two protrusions for supporting the guide shaft 8a on the inner wall surface of the semicircular groove. That is, it is possible to support two points by providing a protrusion at the same place where the V-shaped groove 10 is in contact. Even when the V-shaped groove 10 is provided, the V-shaped tip shape is rounded on the condition that the side surface of the guide shaft 8a is in contact with the two inner wall surfaces of the V-shaped groove 10, or All the angles formed by the inner wall surfaces of adjacent grooves can be made obtuse without sharpening the V-shaped tip. In that case, there exists an advantage which can shape | mold the groove | channel easily.

  Further, the guide shaft 8a and the lens holding member 2 are in contact with each other at two locations separated in the optical axis L direction, or the entire length of the bearing is contacted, and both of them are strongly contacted by the biasing member. If the suppression effect is sufficiently obtained by the rattling suppression means between the lens holding member 2 and the guide shaft 8a, it is not necessary to realize stable three-point support. For example, instead of the V-shaped groove 10 in the lens barrels 1, 1 </ b> A, 1 </ b> B, and 1 </ b> C according to the first, second, third, and fourth embodiments, a rounded groove shape or the like can be used. If it does in this way, there exists an advantage by which shaping | molding in the insertion hole 14 of bearing 9A, 9B, 9C, 9D becomes easy.

  Further, the urging member can be configured without using a spring material. For example, the urging member is configured by replacing the rubber material with a spring material. For example, instead of the coil spring 31 of the lens barrel 1B according to the third embodiment, a rubber material is arranged on the inner wall of the insertion hole 14 of the bearing cylindrical portion 9d by means such as sticking using an adhesive. . Then, the guide shaft 8a is urged toward the V-shaped groove 10 by the elastic force of the rubber material, and the bearing 9C slides along the guide shaft 8a by the urging force.

  In the lens barrels 1, 1A, 1B, and 1C according to the first, second, third, and fourth embodiments, the members to which the urging members are fixed are the bearings 9A, 9B, 9C, and 9D. However, the guide shaft 8a may include an urging member. For example, a rubber material is stuck using an adhesive continuously in the side surface length direction of the guide shaft 8a. The bearing can be configured to slide along the guide shaft 8a by the biasing force of the rubber material in a state where the guide shaft 8a is inserted through the bearing. Further, an urging member such as a rubber material may be provided on both the lens holding member 2 and the guide shaft 8a.

  In the above-described embodiments, the lengths of the bearings 9A, 9B, 9C, and 9D in the optical axis L direction are about 6 mm and 6 mm, but the lengths may be other lengths such as 4 mm, 7 mm, and 10 mm. good. Further, the lengths of the front and rear ends of the bearings 9A, 9B, 9C, and 9D in the optical axis L direction during sliding are 40 mm, but the length may be other lengths such as 30 mm, 15 mm, and 50 mm. good. The length of the bearing in the direction of the optical axis L is preferably 4 mm or more as described above, and more preferably 6 mm or more. Further, the length of the bearing is preferably ½ or less, and more preferably １ ／ or less of the length of the front and rear ends when sliding. In each of the above-described embodiments, 6 mm: 40 mm and approximately 1/7, and if it is 1/6 or less, a large sliding operation is obtained, which is preferable.

  Each of the lens barrels 1, 1A, 1B, and 1C is suitable for application to a camera portion of a camera-equipped mobile phone, but can be applied to various lens products such as a small camera, a surveillance camera, and a mobile camera. Further, the bearings 9A, 9B, 9C, and 9D are preferably applied to extremely small ones such as those having a length of less than 15 mm, but can also be applied to those having a length of 15 mm or more.

  The lens holding member 2 can be formed by injection molding a resin. Also, only the bearings 9A, 9B, 9C, 9D can be formed by injection molding of resin. In these cases, a part of the bearings 9A, 9B, 9C, and 9D can be formed into a shape that can exhibit elasticity, and the lens holding member 2 and the urging member can be integrated. Then, the biasing member biases the guide shaft 8a, so that rattling between the lens holding member 2 and the guide shaft 8a can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the zoom lens barrel which concerns on the 1st Embodiment of this invention, (A) is the principal part longitudinal cross-sectional view, (B) is AA sectional drawing in (A). FIG. 5 is a diagram illustrating a zoom lens barrel according to a second embodiment of the present invention, in which (A) is a longitudinal sectional view of an essential part thereof, and (B) is an AA sectional view in (A). It is a figure which shows the zoom lens barrel concerning the 3rd Embodiment of this invention, (A) is the principal part longitudinal cross-sectional view, (B) is AA sectional drawing in (A). It is a figure which shows the zoom lens barrel based on the 4th Embodiment of this invention, (A) is the principal part longitudinal cross-sectional view, (B) is AA sectional drawing in (A).

Explanation of symbols

1, 1A, 1B, 1C Lens barrel 2 Lens holding member 3 Lens 4 Frame 5a First arm 5b Second arm 6 U-shaped groove 7 Lens barrel body 8a Guide shaft 9A, 9B, 9C, 9D Bearing 9a, 9c, 9e Bearing support portion 9b, 9d, 9f Bearing cylindrical portion 10 V-shaped groove 11 Leaf spring 11a Curved portion 11b Planar portion 11c Locking portion 12 Shaft 14 Insertion hole 14a, 14b Clearance 15 Spring locking hole 21 Leaf spring 21a Leaf spring intermediate portion 21b Leaf spring both ends 21c Locking portion 31 Coil spring 32 Spring retainer 33 Projection 41 Pressing member

Claims (7)

In a lens barrel that includes a lens holding member that holds a lens and receives a guide shaft and moves in the optical axis direction while being guided by the guide shaft.
A lens barrel, wherein a biasing member is provided between the guide shaft and the lens holding member. In a lens barrel that includes a lens holding member that holds a lens and receives a guide shaft and moves in the optical axis direction while being guided by the guide shaft.
A lens barrel characterized in that an urging member is provided between the guide shaft and the lens holding member, and the urging direction by the urging member is a direction toward the center of the guide shaft. In a lens barrel that includes a lens holding member that holds a lens and receives a guide shaft and moves in the optical axis direction while being guided by the guide shaft.
A biasing member is provided between the guide shaft and the lens holding member, and the locations where the guide shaft and the lens holding member abut by the biasing member are a plurality of locations separated in the optical axis direction. A lens barrel characterized by In a lens barrel having a lens holding member that holds a lens and has a bearing having an insertion portion through which a guide shaft is inserted, and that is guided by the guide shaft and moves in the optical axis direction.
A biasing member is provided between the guide shaft and the lens holding member, and the biasing force by the biasing member is applied to the insertion portion in a state where the guide shaft and the bearing are in contact with each other by the biasing member. A lens barrel characterized in that a gap on the side to be applied is made larger than that on the side to receive a biasing force. In a lens barrel that includes a lens holding member that holds a lens and receives a cylindrical guide shaft having a circular cross section that extends in the optical axis direction of the lens and moves in the optical axis direction while being guided by the guide shaft. ,
An urging member is provided between the guide shaft and the lens holding member, and the urging member makes two contact points between the guide shaft and the bearing along the outer periphery of the guide shaft. A lens barrel characterized in that a contact portion between the urging member and the guide shaft is one portion along an outer periphery of the guide shaft, and the guide shaft is supported at three points by the contact portion.   The lens barrel according to claim 1, wherein the biasing member is an elastic body integrated with a lens holding member.   The said biasing member is a leaf | plate spring, and this leaf | plate spring is arrange | positioned so that it may become the other side of the said lens on both sides of the said guide shaft, The one in any one of Claim 1-6 characterized by the above-mentioned. Lens barrel.

Images