JP2011180554A - Lens barrel and optical equipment having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens barrel which achieves comfortable operation by fixing a rotational sliding surface so that fixed operational torque is obtained. <P>SOLUTION: The lens barrel includes: a straight advance barrel which is guided by a rectilinear guide groove of a guiding barrel fixedly coupled with a fixed barrel and moves to straight advance in an optical axis direction, interlocked with rotation of an operation ring supported to be rotatable at a fixed position relative to the fixed barrel; and an adjusting member which is provided between the fixed barrel and the operation ring, and adjusts the rotational torque required to rotate the operation ring, the adjusting member having at least an annular member to generate elastic force in the optical axis direction and a rotation regulating washer. The annular member and the rotation regulating washer are set so that their rotation is regulated by the rotation regulating washer not to rotate relatively to either the fixed barrel or the operation ring, and at least either surfaces of a rotation sliding washer and the fixed barrel or surfaces of the rotation sliding washer and the rotation regulating washer slide each other while abutting in the optical axis direction and relatively rotating. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a lens barrel and an optical apparatus having the lens barrel, and is particularly suitable for a digital camera or a video camera having a mechanism for manually moving a zoom ring or a focus ring to move a lens group for zooming or focusing. It is.

  Conventionally, in digital cameras, video cameras, and the like, zooming and focusing may be performed manually by rotating an operation ring. As a method for adjusting the drive torque (rotational torque) when manually rotating the operation ring, a method of sandwiching an elastic member such as a wave washer or a leaf spring in the gap in the optical axis direction between the fixed member (fixed cylinder) and the operation ring It has been known.

  On the other hand, a lens barrel is known in which a low-friction member is sandwiched between two parts of a fixed cylinder that rotates and slides and an operation ring to prevent wear due to friction. At this time, if the place to rotate and slide is not determined, it may not be known where the low-friction member is rotated, and unevenness in rotational torque may occur, resulting in a poor operational feeling of the operating ring.

  On the other hand, a lens barrel is known in which the rotational torque is adjusted by an annular elastic member fixed to a fixed cylinder in both the optical axis direction and the rotational direction (Patent Document 1). In addition, a lens barrel that fixes a rotating partner of a low-friction member sandwiched between two parts by making a difference in the shape and surface roughness of the sliding surfaces of the two parts that rotate and slide. Is known (Patent Document 2).

JP 2007-240955 A JP 2009-151157 A

  In a digital camera, a video camera, or the like, when zooming or focusing is performed by rotating an operation ring, it is desired to operate with a comfortable operation feeling with less torque unevenness and torque unevenness. The mechanism that adjusts the rotational torque by the annular elastic member is required to have a complicated shape of the elastic member. Further, it is desired that the sliding surfaces of the two parts that rotate and slide can be easily processed, and that the effect of fixing the mating partner is surely ensured.

  In a lens barrel using a conventional wave washer, the surface that rotates and slides cannot be fixed, and especially when the operation ring is reversed, the rotation and sliding surface changes, and the operating torque changes, resulting in an uncomfortable feeling. There was a feeling that there was a certain operation.

  It is an object of the present invention to provide a lens barrel that can obtain a constant operation torque and realize a comfortable operation by fixing a rotary sliding surface.

  Another object of the present invention is to provide a lens barrel that can stabilize the operation torque by using a material having a small friction coefficient for the fixed rotating sliding portion.

  The lens barrel of the present invention includes a fixed tube, an operation ring supported so as to be rotatable at a fixed position with respect to the fixed tube, and a guide tube fixedly connected to the fixed tube in conjunction with the rotation of the operation ring. A linearly-moving cylinder that is guided by the linear guide groove and moves linearly in the direction of the optical axis, and is provided between the fixed cylinder and the operating ring, and urges the fixed cylinder or the operating ring toward the optical axis. The lens barrel includes an adjustment member that adjusts the rotational torque required to rotate the operation ring. The adjustment member includes an annular member that generates an elastic force at least in the optical axis direction and a rotation restricting washer. The annular member and the rotation restricting washer are restricted by the rotation restricting washer so that they cannot rotate relative to either the fixed cylinder or the operating ring, and the rotary sliding washer and the fixed cylinder or Between the operating rings or rotating slide At least one of between the washer and the rotation restricting washer is characterized in that slide each other while in contact with the relative rotation in the direction of the optical axis.

  According to the present invention, it is possible to obtain a lens barrel that can stabilize the operation torque by using a material having a small friction coefficient for the fixed rotating sliding portion.

Sectional drawing of the principal part of the lens barrel of the Example of this invention 1 is a perspective view of a cross section of a main part of a part of FIG.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The lens barrel of the present invention is detachably attached to the camera body. A fixed cylinder 15 and an operation ring (zoom ring) 1 supported so as to be rotatable at a fixed position relative to the fixed cylinder 15 are provided. Further, in conjunction with the rotation operation of the operation ring 1, there is a rectilinear cylinder 6 that is guided by the rectilinear guide groove 11 of the guide cylinder 10 fixedly connected to the fixed cylinder 15 and moves linearly in the optical axis direction. Provided between the fixed cylinder 15 and the operation ring 1, and adjust the rotational torque required to rotate the operation ring 1 by urging the fixed cylinder 15 or the operation ring 1 with respect to the direction of the optical axis. And an adjustment member. The adjustment member includes an annular member (wave washer) 18 that generates an elastic force at least in the optical axis direction, a rotation restricting washer 19, and a rotary sliding washer 20.

  The annular member 18 and the rotation restricting washer 19 are restricted from rotating relative to the operation ring 1 by engaging a convex portion 21 provided on the rotation restricting washer 19 and a concave portion 22 provided on the operation ring 1. . At least one of the rotary sliding washer 20 and the fixed cylinder 15 or the operation ring or between the rotary sliding washer 20 and the rotation restricting washer 19 is a surface that abuts in the optical axis direction and slides relative to each other while relatively rotating. ing. Further, the rotary sliding washer 20 is made of a material having a lower (smaller) friction coefficient than the rotation restricting washer 19.

  FIG. 1 is a cross-sectional view of a main part of a lens barrel that can be attached to and detached from a camera body according to Embodiment 1 of the present invention. FIG. 1 shows only the part relating to the description of the lens barrel of the present invention, and the present invention can be applied to other configurations. In FIG. 1, reference numeral 1 denotes a zoom ring (operation ring), which is mechanically fixed to an exterior ring 2 provided on the outer periphery thereof. A zoom ring rubber 3 is fixed to the outer periphery of the exterior ring 2. One or more guide grooves 5 are formed on the inner periphery of the zoom ring 1. Reference numeral 6 denotes a rectilinear cylinder, and a zoom ring roller 4 is fixed to the outer periphery thereof. The zoom ring 1 is fitted into a guide groove 5 on the inner periphery of the zoom ring 1 to connect the zoom ring 1 and the rectilinear cylinder 6. ing. A first group roller 9 is fixed to the inner periphery of the rectilinear cylinder 6, and the first group roller 9 passes through a rectilinear guide groove 11 provided in the guide cylinder 10 and a cam groove (not shown) provided in the cam ring 12. is doing. As a result, the three parts of the straight cylinder 6, the guide cylinder 10, and the cam ring 12 are connected.

  The zoom ring 1 is held by a bayonet connection with respect to a groove provided in the guide tube 10 and rotates at a fixed position without moving in the optical axis direction. The guide groove 5 provided in the zoom ring 1 is formed in a spiral shape on the inner periphery of the zoom ring 1. By rotating the zoom ring 1 at a fixed position, the rectilinear cylinder 6 moves straight along the cam groove of the cam ring 12 and toward the subject side while being guided by the rectilinear guide groove 11 of the guide cylinder 10.

  The first lens barrel 7 is fixed to the rectilinear barrel 6, and the first lens group 8 fixed to the first lens barrel 7 by caulking or bonding simultaneously moves in the optical axis direction (object side or image side). . At this time, the guide tube 10 is connected and fixed to a fixed tube 15 fixedly connected to the camera body, and neither rotates nor moves in the optical axis direction. The cam ring 12 is bayonet-coupled to the guide tube 10 (not shown) and rotates at a fixed position without moving in the optical axis direction. Further, a third group roller 14a is fixed to the third group lens barrel 14, and this roller 14a is connected by the cam groove of the cam ring 12 and the third group guide groove 13 of the guide cylinder 10, and the cam ring 12 is fixed. By rotating the position, the third lens barrel 14 moves in the optical axis direction (object side or image side). At this time, the third lens group 16 is fixed to the third group barrel 14 by caulking or bonding.

  The user holds the zoom ring rubber 3 attached to the outside of the exterior ring 2 fixed to the zoom ring 1 and performs a zoom operation by manually turning. When the zoom ring 1 is turned, the first lens group 8 and the third lens group 16 advance and retreat in the optical axis direction as described above, thereby enabling zooming. At this time, as shown in FIG. 2, the portion A in FIG. 1 has several zoom torque adjustments and comfortable operation feelings simultaneously in the gap in the optical axis direction between the fixed cylinder 15 and the zoom ring (operation ring) 1. The parts are arranged. Normally, a focus lens group (not shown), a mechanism for moving the focus lens group (not shown), and an image sensor (not shown) such as a CCD or CMOS are arranged on the image plane side (the opposite side of the first lens group 8) in the optical axis direction. However, since these are not the gist of the present invention, the description is omitted.

  Although the present embodiment describes the zoom operation, the same effect can be obtained by performing the same configuration for the focus operation. In addition, this embodiment generally assumes an interchangeable lens for a single-lens reflex camera, but the same applies to a camera or a video camera having a lens barrel for manually performing zooming or focusing operation. Is done. In the above description, the fixed cylinder 15 is fixed to the camera body. However, as a result of being connected one or more times from the parts fixed to the camera body, both the optical axis direction and the rotation direction are fixed. Applicable even in the state. Next, a specific embodiment will be described with reference to FIG.

[Example 1]
The features of the lens barrel of the embodiment of the present invention will be described below with reference to FIG. FIG. 2 is a view for facilitating the understanding of the cross-sectional view of the main part of the lens barrel of the present invention when viewed obliquely. The zoom ring 1 is a component that rotates at a fixed position as described above. The fixed cylinder 15 does not rotate or move in the optical axis direction. A torque adjustment washer 17, a wave washer 18, a rotation restricting washer 19, and a rotary sliding washer 20 are arranged in this order from the zoom ring 1 side in the gap between the zoom ring 1 and the fixed cylinder 15.

  The torque adjustment washer 17 adjusts the torque when the zoom ring 1 is rotated. The wave washer 18 is inserted between the zoom ring 1 and the fixed cylinder 15 and applies a rotational torque to the zoom ring 1 by a frictional force generated by the wave washer. The wave washer 18 is made of an annular member that generates an elastic force. In order to simplify the description below, the annular member is called a wave washer. The convex portion 21 of the rotation restricting washer 19 is fitted in the concave portion 22 of the zoom ring 1, and the rotation restricting washer 19 rotates integrally with the zoom ring 1, and both cannot be rotated relative to each other.

  In this embodiment, the wave washer 18 and the rotation restricting washer 19 are restricted from rotating relative to the fixed cylinder 15 such that the convex part of the rotation restricting washer 19 is fitted in the recess provided in the fixed cylinder 15. May be. In that case, a rotation sliding washer 20, a rotation restricting washer 19, a wave washer 18, and a torque adjustment washer 17 are arranged in this order from the zoom ring 1 side in the gap between the zoom ring 1 and the fixed cylinder 15.

  In this embodiment, when the zoom ring 1 is rotated, the torque adjustment washer 17, the wave washer 18, and the rotation restricting washer 19 rotate around the fixed cylinder 15 along with the zoom ring 1. On the other hand, whether or not the rotary sliding washer 20 is rotated according to the rotation restricting washer 19 depends on various conditions such as the friction coefficient, weight, and angular velocity during rotation.

  In the present embodiment, it is not necessary to specify whether to carry around or not. Further, since the fixed cylinder 15 is fixed, it does not rotate. Accordingly, the two components that rotate relative to each other while being in contact with each other are the rotation restricting washer 19 (zoom ring) versus the rotation sliding washer 20 or the rotation sliding washer 20 versus the fixed cylinder 15. Therefore, one of the two parts that rotate relative to each other is a rotary sliding washer 20.

  In general, the rotary sliding washer 20 is made of a material having a small coefficient of friction so that a smooth and smooth feel can be obtained when the rotary operation is performed. The rotation sliding washer 20 uses a material having a lower friction coefficient than the rotation regulating washer 19. When the rotary sliding washer 20 is not used, the two parts that rotate relative to each other serve as the rotation restricting washer 19 and the fixed cylinder 15. In this case, the fixed cylinder 15 side of the rotation restricting washer 19 needs to be processed with a small surface roughness in order to reduce the friction coefficient, and the usable material range is also narrowed.

  Further, the rotation restricting washer 19 constantly receives the rotational torque input by the zoom ring 1 at its convex portion 21 and receives several times the force when it receives an impact such as a drop. It must be strong enough not to break. Therefore, the rotation restricting washer 19 needs to be a material having a predetermined thickness and a predetermined mechanical strength. And special processing is required to smooth the surface of the material. On the other hand, according to the present embodiment, the rotary sliding washer 20 is thin and may have a simple circular shape, so that a metal or sheet material or the like can be easily manufactured and a highly versatile material can be used. . Further, even when the rotation operation of the zoom ring 1 is reversed (the rotation direction is reversed), the sliding surface relatively rotated by the rotation restricting washer 19 is fixed, so that an operational feeling without a sense of incongruity can be obtained. In the case where there is no rotation restricting washer 19, it is not fixed which part is rotated together with the zoom ring 1, so that the sliding surface may be changed particularly during reversal depending on the above conditions such as the coefficient of friction. . In that case, as a manual rotation operation, it is felt that the rotational torque changes irregularly, and the operation feeling becomes very unpleasant. On the other hand, in this embodiment, the rotational torque does not change during reversal, so that a comfortable feeling of rotational operation can be obtained. Further, if oil or the like for adjusting the sliding resistance of the surface is applied, a more stable operational feeling can be obtained. In the case of the present embodiment, only the rotary sliding washer 20 needs to be coated with oil, so that the amount of oil used and work can be reduced.

  As described above, in this embodiment, at least three components of the wave washer 18, the rotation restricting washer 19, and the rotation sliding washer 20 are inserted between the fixed cylinder 15 and the operation ring 1 in the optical axis direction. Then, by fitting the rotation restricting convex portion 21 or the concave shape provided in the rotation restricting washer 19 into the concave or convex shape of either the fixed tube 15 or the operation ring 1, the fixed tube 15 or the operation ring 1 is attached. And fix it so that relative rotation is impossible. The two parts that slide while making relative rotation in contact with the optical axis direction are always the rotation sliding washer 20 and the fixed cylinder 15, or the rotation regulating washer 19 supported by the rotation sliding washer 20 and the operation ring so as not to be relatively rotatable. It can be fixed to. As a result, it is possible to adjust the rotational torque when the operation ring 1 is rotated, and to realize a comfortable operation feeling without torque unevenness.

  In addition, a wave washer 18 is inserted between the operation ring 1 and the fixed cylinder 15, and a rotational torque is applied to the operation ring 1 by the frictional force generated by the wave washer 18 to adjust the operational feeling. The operational feeling during rotation is improved. In particular, according to this embodiment, a lens barrel can be obtained in which the operating torque is changed when the rotation direction is reversed, and the operational feeling does not feel uncomfortable. In addition, the lens barrel of the present embodiment can be applied to an optical apparatus such as a digital camera or a video camera having a solid-state imaging device that receives an image via the lens barrel.

1: Zoom ring 2: Exterior ring 5: Guide groove 6: Straight tube 10: Guide tube 11: Straight guide groove 12: Cam tube 14: Third group lens barrel 15: Fixed tube 17: Torque adjustment washer 18: Wave washer 19: Rotation restricting washer 20: Rotating sliding washer 21: Convex part 22: Concave part

Claims (3)

  The fixed cylinder, the operation ring supported so as to be rotatable at a fixed position with respect to the fixed cylinder, and being guided by the straight guide groove of the guide cylinder fixedly connected to the fixed cylinder in conjunction with the rotation of the operation ring. A rectilinear cylinder that moves linearly in the optical axis direction, and is provided between the fixed cylinder and the operating ring, and rotates the operating ring by urging the fixed cylinder or the operating ring with respect to the direction of the optical axis. The lens barrel includes an adjustment member that adjusts the rotational torque required for the lens barrel, and the adjustment member has an annular member that generates elastic force at least in the optical axis direction and a rotation restricting washer. The rotation restricting washer is restricted by the rotation restricting washer so as not to rotate relative to either the fixed cylinder or the operation ring, and between or between the rotation sliding washer and the fixed cylinder or the operation ring. Sliding washers and rotation regulation A lens barrel, wherein a slide together with the relative rotation contact with the optical axis at least one among between Ssha.   2. The lens barrel according to claim 1, wherein the rotational sliding washer has a lower coefficient of friction than the rotation restricting washer.   An optical apparatus comprising: the lens barrel according to claim 1 or 2; and a solid-state imaging device that receives an image via the lens barrel.