JP2008233771A - Lens barrel and optical equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixed barrel member obtained by integrally forming an outer barrel and an inner barrel through the use of a flange part, and to suppress the axial deviation between an intermediate barrel member that is rotatably engaged with the outer peripheral part of the inner barrel and the fixed barrel member in a part where the outer barrel and the inner barrel overlap each other in the optical axis direction, and to obtain highly accurate coaxiality. <P>SOLUTION: The lens barrel includes: the fixed barrel member obtained by integrally connecting the outer barrel part and the inner barrel part that partly overlap each other along the optical axis direction through the use of the flange part while leaving a distance between them in a direction orthogonal to the optical axis; an operating member that is rotatably disposed on the outer periphery of the outer barrel part; the intermediate barrel member that is rotatably disposed on the inner barrel part and rotated with the rotation of the operating member; and a lens frame for holding a lens, that is disposed at the inside of the inner barrel part so that it can move in the optical axis direction, and that is moved in the optical axis direction with the rotation of the intermediate barrel member. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical apparatus such as a camera system including a lens barrel and a camera body mounted with the lens barrel.

  In general, a zoom lens barrel has a mechanism for moving a lens frame holding a lens in a direction of an optical axis along a predetermined locus by a fixed-position rotational movement with respect to a guide tube having a rectilinear groove and a cam tube having a cam groove. Are known. In addition, in order to perform the zoom operation and the focus operation, a desired zoom operation and focus operation can be performed by transmitting the fixed position rotation of the rotation operation member with respect to the fixed member to the cam ring and the relay member.

  Particularly in recent years, since the lens barrel is required to be downsized in the optical axis direction and the radial direction, the zoom operation and focus operation mechanisms have to be configured in a narrow space and are complicated mechanisms. .

In the lens barrel of Patent Document 1, the lens frame that advances and retreats in the optical axis direction by focusing and zooming is bayonet-coupled to the helicoid ring that supports the lens frame and the inner periphery of the helicoid ring. Further, since the helicoid ring advances and retracts in the optical axis direction, the lens frame can also advance and retract in the optical axis direction. Conventionally, the lens frame is helicoid-coupled on the outer peripheral side of the helicoid ring, and the helicoid ring rotates at a fixed position with respect to a member supporting the helicoid ring. Therefore, in the structure of patent document 1, it is not necessary to have a sleeve part for a lens frame to carry out helicoid coupling in the outer peripheral part of a helicoid ring. Furthermore, it is possible to reduce the size of the lens barrel by reducing the number of members laminated in the radial direction.
JP 2006-145562 A

  However, although Patent Document 1 achieves a reduction in the radial direction, the axial displacement between the constituent members cannot be suppressed. In Patent Document 1, the fixed cylinder is composed of an outer cylinder and an inner cylinder, and is fixed to the rear end portion of the inner cylinder at the flange portion at the rear end portion of the outer cylinder by a fastening member to be integrated. The constituent members of the lens barrel assembled between the outer cylinder and the inner cylinder are assembled from the front side and are fitted to the outer periphery of the inner cylinder. The position in the optical axis direction is regulated by bayonet coupling with respect to the inner cylinder.

  A member that fits to each of the outer cylinder and the inner cylinder with respect to the fixed cylinder by causing an axial deviation between the outer cylinder and the inner cylinder if the axial deviation element due to the backlash of the outer cylinder and the inner cylinder is not eliminated. This will directly affect the misalignment.

  Therefore, the present invention provides an integrated fixed cylinder member in which an outer cylinder and an inner cylinder are connected by a flange portion, and is a portion where the outer cylinder and the inner cylinder overlap with each other in the optical axis direction so that the outer cylinder and the inner cylinder can rotate around the outer circumference of the inner cylinder. An object of the present invention is to suppress axial misalignment between the intermediate cylindrical member and the fixed cylindrical member to obtain a highly accurate coaxiality.

  In the present invention, a fixed cylinder member in which an outer cylinder part and an inner cylinder part, which are partially overlapped in the optical axis direction, are integrally connected by a flange part at an interval in the optical axis orthogonal direction, and the outer cylinder part An operation member that is rotatably provided on the outer periphery, an intermediate cylinder member that is rotatably provided on the inner cylinder portion and is rotated by the rotation of the operation member, a lens is held, and an optical axis direction is provided on the inner side of the inner cylinder portion And a lens frame that is moved in the optical axis direction by rotation of the intermediate cylinder member.

  Further, in the present invention, the outer cylinder part and the inner cylinder part that are overlapped along the optical axis direction are connected by a flange part, and the outer part from the direction of the optical axis with respect to the flange part. An intermediate cylinder member incorporated between the cylinder part and the inner cylinder part, wherein the intermediate cylinder member is rotatably engaged with the inner cylinder part of the fixed cylinder member by a bayonet part, and the bayonet part is The fixed cylinder member has a bayonet engaging groove and the intermediate cylinder member has a bayonet claw having a diameter smaller than the fitting diameter. The fixed cylinder member has a fitting diameter with the intermediate cylinder member and the bayonet. The bayonet part is provided in the area of the opening provided in the outer cylinder part of the fixed cylinder member, and the intermediate cylinder member is incorporated in the fixed cylinder member. In the optical axis direction with respect to the fitting portion. The parts are characterized by having a small-diameter portion of diameter smaller than the fitting portion on the opposite side.

  Further, according to the present invention, the outer cylinder part and the inner cylinder part that are overlapped along the optical axis direction are connected by a flange part, and the outer part from the direction of the optical axis with respect to the flange part. An intermediate cylinder member incorporated between the cylinder part and the inner cylinder part, wherein the intermediate cylinder member is rotatably engaged with the inner cylinder part of the fixed cylinder member by a bayonet part, and the bayonet part is The fixed cylinder member has a bayonet claw portion, the intermediate cylinder member has a bayonet engagement groove, and the fixed cylinder member has a position of a bayonet portion and a fitting diameter with the intermediate cylinder member. The bayonet portion is provided in the region of the opening provided in the outer cylinder portion of the fixed cylinder member in order from the flange portion side, and the intermediate cylinder member is incorporated in the fixed cylinder member in the optical axis direction. In front of the fitting portion on the opposite side to the flange portion It is characterized by having a small-diameter portion of diameter smaller than the fitting portion.

  According to the present invention, an integrated fixed cylinder member in which an outer cylinder and an inner cylinder are connected by a flange portion, and the outer cylinder and the inner cylinder are rotatable at the outer peripheral portion of the inner cylinder at a portion where the outer cylinder and the inner cylinder overlap in the optical axis direction. The axial displacement between the engaging intermediate cylinder member and the fixed cylinder member is suppressed, and the accuracy of the coaxiality can be improved.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view of a lens barrel of an embodiment of the present invention, and shows an upper half centering on the optical axis. In FIG. 1, reference numeral 100 denotes a lens barrel, 200 denotes a camera body, and the lens barrel 100 is mounted on the camera body 200 to constitute a camera system (optical device). Here, a correspondence is shown in which the lens barrel is mounted on the camera body as an optical device, but an imaging device (optical device) in which the lens barrel is integrally provided on the camera body may be used. FIG. 2 is a perspective view of some lens barrel components related to the focus unit and zoom operation. FIG. 3 is a perspective view of a first moving cylinder that supports a second group unit and a fourth group unit described later. FIG. 4 is a perspective view of components of a focus unit which will be described later.

  In these drawings, reference numerals 1 to 4 denote lens group units that hold the photographing lens and move it in the optical axis direction. Reference numeral 1 denotes a first group unit, and reference numeral 2 denotes a second group unit (lens barrel unit) as a lens frame, which is divided into a 2A lens group unit 2a and a 2B lens group unit 2b which are focus lens groups. Reference numeral 3 denotes a third group unit in which the first light amount adjusting member 3a and the second light amount adjusting member 3c are integrally coupled to a third group barrel 3b holding a lens. Reference numeral 4 denotes a fourth group unit in which a fourth group first unit 4a (hereinafter referred to as 4-1 group unit 4a) and a fourth group second unit 4b (hereinafter referred to as 4-2 group unit 4b) are integrally coupled.

  The lens barrel of this embodiment includes a fixed cylinder 5, a guide cylinder 6 as a fixed cylinder member, a cam cylinder 7, a first moving cylinder 8 (hereinafter referred to as a 2-4 group moving cylinder 8), and a second moving cylinder. 9 (hereinafter referred to as a first group moving cylinder 9). The lens barrel further includes an adjustment key 10, a relay cylinder 11 as an intermediate cylinder member, a relay key 12, a focus unit 13, a zoom operation ring 14, a focus operation ring 15 as an operation member, a mount 16, and a base unit 17. .

  The zoom operation ring 14 is fitted to the outer periphery of the fixed cylinder 5 and rotates at a fixed position with respect to the fixed cylinder 5. When the zoom operation ring 14 is rotated in the zoom operation, the zoom lever 18 shown in FIG. 2 rotates synchronously. The zoom lever 18 is fixed to the cam cylinder 7, and the cam cylinder 7 is also rotated around the optical axis. The zoom lever 18 slides with respect to the circumferential groove 19 provided in the guide cylinder 6 and at the same time restricts the movement of the cam cylinder 7 in the optical axis direction. Further, the outer peripheral portion of the cam cylinder 7 is fitted to the inner peripheral portion of the guide cylinder 6.

  During zoom operation, the second group unit 2 and the fourth group unit 4 move together with the 2-4 group moving cylinder 8 (hereinafter referred to as the 2-4 group unit 20) in the optical axis direction. The first group unit 1 is supported by the first group moving cylinder 9 by a cam follower. The first group moving cylinder 9, the 2-4 group unit 20, and the third group unit 3 include a cam follower that supports each member in a cam groove 21 provided in the cam cylinder 7 and a rectilinear groove 22 provided in the guide cylinder 6. And move straight in the optical axis direction as the zoom operation ring 14 rotates.

  The focus operation ring 15 is fitted to the outer periphery of the guide tube 6 and rotates at a fixed position with respect to the guide tube 6. The focus operation ring 15 and the focus unit 13 rotate the focus key 23 by a half of the rotation angle of the focus operation ring 15 by a known operation mechanism. The focus key 23 is engaged with the adjustment key 10, and the adjustment key 10 is fixed to the relay cylinder 11 that is an intermediate cylinder member. The relay cylinder 11 is bayonet-coupled to the guide cylinder 6 and rotates at a fixed position, and the relay key 12 fixed to the relay cylinder 11 is engaged with the 2A group unit 2a by the engaging portion 2c (see FIG. 3). The cam follower that supports the 2A group unit 2a is engaged with the cam groove 24 of the 2-4 group moving cylinder 8 shown in FIG. With the focus operation, the focus key 23, the adjustment key 10, the relay cylinder 11, and the relay key 12 are rotated. As a result, the 2A group unit 2a moves along the cam groove 24 and advances and retreats in the optical axis direction (the 2A group unit 2a as a lens frame is provided inside the guide tube 6 so as to be movable in the optical axis direction. ing).

  The focus unit 13 is in contact with and fixed to the guide tube 6 at the front end face of the focus unit 13. The screw 25 fastened to the outer periphery of the guide cylinder 6 shown in FIG. 2 is located behind the rear end face of the focus unit base 13a that is a constituent member of the focus unit 13. The washer member 13b shown in FIG. 1, which is a component of the focus unit 13, is bayonet-coupled to the focus unit base 13a.

  As shown in FIG. 4, the wall portion 26 forming the bayonet groove 13c of the focus unit base 13a is thin in the optical axis direction at the introduction portion 27 of the washer member 13b. This is because the bayonet groove 13c is perpendicular to the optical axis in order to increase the force with which the first focus driving member 13d is pressed against the second focus driving member 13e as the amount of screwing the washer member 13b into the focus unit base 13a increases. This is because it is inclined with respect to the angle. For this reason, when an external force such as an impact is applied to the lens barrel, the introduction portion 27 may be broken and dispersed. Therefore, the screw 25 supports the wall portion 26 even if an external force is applied to the wall portion 26 by impact by fastening the screw 25 close to the wall portion 26 to the guide tube 6, and cracking of the wall portion 26 is prevented. Prevents and keeps on deforming.

  The mount 16 is fixed to the fixed cylinder 5 with a waterproof rubber member 28 and a back focus adjusting member 29 (hereinafter referred to as a mount ring 28) sandwiched between the fixed cylinder 5. Reference numeral 17 denotes a base unit including an electrical contact and an IC element for performing communication with the camera body, and is fixed to the fixed cylinder 5. The filter frame unit 30 is fitted to the inner periphery 6 a of the guide tube 6 and is fastened from the outer periphery of the guide tube 6.

  Next, characteristic points of the lens barrel of the first embodiment will be described with reference to FIGS.

  FIG. 5 shows a cross-sectional view of the guide cylinder 6 which is a fixed cylinder member. FIG. 6 shows an enlarged view of a broken line portion shown in FIG. The guide tube 6 has an outer tube portion 101 and an inner tube portion 102. The outer cylinder portion 101 and the inner cylinder portion 102 are located in a region where they overlap each other in the optical axis direction, are connected and connected by a flange portion 103, and are integrally formed with a space in a direction orthogonal to the optical axis. FIG. 7 is a cross-sectional view of the relay cylinder 11 that is an intermediate cylinder member that is bayonet-coupled with the guide cylinder 6 on the outer periphery of the inner cylinder portion 102 and rotates at a fixed position with respect to the guide cylinder 6. FIG. 8 is an enlarged view of a broken line portion shown in FIG.

  5 and 6, the outer tube portion 101 and the inner tube portion 102 of the guide tube 6 overlap in the optical axis direction and form a space in the direction orthogonal to the optical axis. Are bayonet combined. In the present embodiment, the bayonet groove 104 is provided on the guide tube 6 side, and the bayonet claw 105 is provided on the relay tube 11 side, thereby restricting both members relative to the optical axis direction. Further, the radial position is determined by the fitting portions 106 and 107 (shown in FIGS. 6 and 8).

  In order to realize a structure in which the relay cylinder 11 rotating at a fixed position is assembled on the inner diameter side of the outer cylinder portion 101 of the guide cylinder 6 at a position overlapping the outer cylinder portion 101 in the optical axis direction, conventionally, the inner cylinder portion 102 is A corresponding member (hereinafter, referred to as a separate internal cylinder member) is fixed to the guide cylinder 6. As a result, when the separate cylinder member is assembled to the guide cylinder 6 with respect to the fixed guide cylinder 6, the relay cylinder 11 is misaligned with the guide cylinder 6. The axial displacement of the guide cylinder 6 will be affected.

  Therefore, by forming the inner cylinder portion 102 integrally with the guide cylinder 6, the axial displacement of the relay cylinder 11 with respect to the guide cylinder 6 is suppressed, and a highly accurate coaxiality between the relay cylinder 11 and the guide cylinder 6 is achieved. Can be obtained. Furthermore, the coaxiality of other constituent members with respect to the guide tube 6 can be improved with high accuracy.

  Next, the location which concerns on the bayonet coupling structure between the guide cylinder 6 and the relay cylinder 11 in a present Example is demonstrated.

  In this embodiment, the bayonet coupling between the guide tube 6 and the relay tube 11 is performed by arranging fitting diameters 106, 107, bayonet grooves 104, and bayonet claws 105 in order from the flange portion 103, as shown in FIGS. ing. In addition, an opening 108 is provided on the outer periphery of the outer cylinder portion 101, and a bayonet coupling portion (bayonet groove 104, bayonet claw 105) is in the opening 108. The role of the opening 108 will be described later.

  In addition, as shown in FIGS. 7 and 8, the relay cylinder 11 is on the side opposite to the flange 103 of the guide cylinder 5 with respect to the fitting diameter 107 in the optical axis direction in which the relay cylinder 11 is assembled with the guide cylinder 6. It has a smaller diameter portion 109 than the fitting diameter 107. The role of the small diameter portion 109 will be described later.

  In general, a place where accuracy such as a fitting portion is required is strictly controlled by a gauge or the like. For example, when measuring the fitting diameter of a member having a fitting diameter on the outer peripheral portion (hereinafter referred to as an outer fitting member), a plurality of cylindrical gauges whose inner diameter is approximate to the fitting diameter are used. When the gauge is assembled to be fitted to the outer circumference fitting member, if the fitting diameter dimension of the outer circumference fitting member is larger than the inner diameter dimension of the gauge, the outer circumference fitting member and the gauge cannot be assembled. On the other hand, if the fitting diameter of the outer peripheral fitting member is smaller than the inner diameter of the gauge, the outer fitting member and the gauge can be assembled with backlash in the radial direction. In this way, the distance between the fitting diameters of the outer peripheral fitting members among the inner diameters of the plurality of gauges is searched, and the fitting diameter is measured.

  When the groove width of the groove portion requires accuracy, the groove width is measured using a plurality of rod-like gauges having a diameter approximate to the groove width dimension in the same manner as the fitting diameter dimension measurement using the gauge described above.

  In the present embodiment, as described above, there is a small-diameter portion 109 whose diameter is smaller than the fitting diameter 107 of the relay cylinder 11. Therefore, in order to gauge the fitting diameter 107, it is necessary that the fitting diameter 107, the bayonet claw 105, and the small diameter portion 109 are arranged in order from the flange portion 103 in a state where the relay cylinder 11 is assembled in the guide cylinder 6. is there.

  Further, in order to measure the groove width of the bayonet groove 104 also on the guide tube 6 side, the bayonet groove 104 is in the opening portion 108 and needs to be measured from the opening portion 108.

  According to the embodiment described above, the outer cylinder and the inner cylinder are integrated into a fixed cylinder member, and the outer cylinder and the inner cylinder are rotatably engaged with the outer peripheral portion of the inner cylinder at the portion where the outer cylinder and the inner cylinder overlap in the optical axis direction. The axial displacement between the intermediate cylinder member and the fixed cylinder member is suppressed, and a highly accurate coaxiality can be obtained.

  In the above embodiment, the bayonet groove 104 is provided on the guide cylinder 6 side which is a fixed cylinder member and the bayonet claw 105 is formed on the relay cylinder 11 which is an intermediate cylinder member, but the bayonet claw is provided on the guide cylinder 6 side. The bayonet groove may be formed in the relay cylinder 11.

Sectional view of the lens barrel in the embodiment Perspective view of some lens barrel components showing the zoom actuation mechanism Perspective view of 2-4 group unit Perspective view of the focus unit base Cross section of guide tube 5 is an enlarged view of the broken line portion Cross section of relay tube 7 is an enlarged view of the broken line portion

Explanation of symbols

2a 2A group unit 6 Guide tube 11 Relay tube 15 Focus operation ring 101 Outer tube portion 102 Inner tube portion 103 Flange portion

Claims (2)

A fixed cylinder member in which an outer cylinder part and an inner cylinder part, which are partially overlapped along the optical axis direction, are integrally connected with a flange part at intervals in the optical axis orthogonal direction;
An operation member rotatably provided on the outer periphery of the outer cylindrical portion;
An intermediate cylinder member that is rotatably provided in the inner cylinder part and rotates by rotation of the operation member;
A lens barrel that holds a lens and is provided inside the inner cylinder portion so as to be movable in the optical axis direction, and is moved in the optical axis direction by the rotation of the intermediate cylinder member. . A lens barrel according to claim 1;
An optical apparatus comprising: a camera body on which the lens barrel is mounted.

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