JP4697588B2 - Lens barrel - Google Patents

Description

  The present invention relates to a lens barrel, and more particularly to a lens barrel mounted on a surveillance camera.

  The lens barrel is connected to the camera via a connecting member called a lens mount. Usually, the lens barrel and the connecting member are fixed with screws or the like. The connecting member is required to have sufficient mechanical strength in order to prevent breakage due to an unintentional strong force or impact when the camera is mounted. For this reason, various proposals for improving the mechanical strength have been made with respect to the connecting member of the lens barrel.

For example, Patent Document 1 describes a connecting member in which a screw fixing portion for a lens barrel and a bayonet claw that engages with a camera are reinforced with a metal member. According to this connecting member, since the strength of the screw fixing portion and the bayonet claw is increased, the connecting member can be fixed to the lens barrel with a strong tightening force, and the engaging force between the connecting member and the camera is improved. Can be made. Thereby, it is possible to prevent the connecting member from being damaged by an inadvertent force or impact when the camera is mounted.
JP 2000-29116 A

  However, Patent Document 1 has a problem that distortion occurs in the lens barrel body of the lens barrel by fixing the connecting member to the lens barrel with a strong tightening force. Further, since the distortion occurs in the lens barrel main body, the sliding resistance between the operation ring such as the focus ring and the zoom ring and the lens barrel main body increases, resulting in a problem that the operability is deteriorated.

  Further, in Patent Document 1, when the connecting member is screwed to the lens barrel with a strong tightening force, the thread of the female screw on the lens barrel body side is destroyed, and the lens barrel body itself needs to be replaced. there were.

  The present invention has been made in view of such circumstances, and a lens capable of reliably fixing a connecting member to the lens barrel body of the lens barrel and preventing distortion and damage of the lens barrel body. An object is to provide a lens barrel.

To achieve the pre-Symbol object, a first aspect of the present invention, a lens barrel body, the lens barrel and a connecting member connected to the camera is fixed to said mirror barrel body, the barrel One of the first cylindrical members made of the main body or the connecting member is provided with an elastic member extending in the circumferential direction from the front end of a support portion that protrudes in the optical axis direction from the end surface of the first cylindrical member. An engagement portion formed in the circumferential direction on the inner peripheral surface of the second cylindrical member is provided with a deformable arm and the other second cylindrical member made of the lens barrel body or the connecting member . The arm has a convex portion or a concave portion formed on the end surface side of the first cylindrical member, and the engaging portion has a concave portion corresponding to the convex portion or the concave portion of the arm. Alternatively, a convex portion is formed, and the engagement portion is sandwiched between the end surface of the first cylindrical member and the arm. It characterized that you connecting the first and second tubular member by engaging the projections or recesses of said arm in state in recesses or protrusions of the engagement portion.

According to the present invention, since the lens barrel main body and the connecting member of the lens barrel are connected using the snap-in mechanism, the lens barrel main body and the connecting member can always be connected with an appropriate force. It is possible to prevent distortion from occurring in the trunk body. In addition, according to the present invention, the lens barrel body and the connecting member are connected using the snap-in mechanism, so that a fixing member such as a screw or a fixing tool is not required, and the lens barrel body and the connecting member can be easily provided. And it can connect at low cost. In particular, according to the present invention, since the connecting member and the lens barrel main body can be connected in a state of being positioned in the optical axis direction, the optical characteristics of the lens barrel can be improved.

According to the present invention, since the lens barrel main body and the connecting member of the lens barrel are connected using the snap-in mechanism, the lens barrel main body and the connecting member can always be connected with an appropriate force. It is possible to prevent distortion from occurring in the trunk body. In addition, according to the present invention, since the lens barrel body and the connecting member are connected using the snap-in mechanism, a fixing member such as a screw or a fixing tool is not required, and the lens barrel body and the connecting member can be easily provided. And it can connect at low cost. In particular, according to the present invention, since the connecting member and the lens barrel main body can be connected in a state of being positioned in the optical axis direction, the optical characteristics of the lens barrel can be improved.

  Hereinafter, preferred embodiments of a lens barrel according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a side sectional view showing a configuration of a lens barrel 10 that is mainly mounted on a surveillance camera. The lens barrel 10 shown in FIG. 1 mainly includes a substantially cylindrical barrel body 12 (also referred to as a fixed barrel), and a connecting member 14 (attached to the base end portion of the barrel body 12 and coupled to a camera 18). A lens mount) and a diaphragm device 16 that is inserted into the lens barrel body 12 from the peripheral surface side.

  The lens barrel body 12 includes a large-diameter portion 12A on the distal end side and a small-diameter portion 12B on the proximal end side, and the large-diameter portion 12A and the small-diameter portion 12B are integrally formed of resin. The focus ring 20 is rotatably supported on the outer peripheral surface of the large diameter portion 12A, and the zoom ring 30 is rotatably supported on the outer peripheral surface of the small diameter portion 12B.

  A focus lens (group) 22 held on the lens frame 24 is disposed on the optical axis P inside the large diameter portion 12A of the lens barrel body 12. An engaging portion 24C protrudes from the outer peripheral surface of the lens frame 24. The engaging portion 24C is engaged with a rectilinear groove 12C formed in the optical axis P direction on the large diameter portion 12A. Thereby, the lens frame 24 and the focus lens (group) 22 are supported movably in the optical axis P direction.

  A cam pin 26 protrudes from the engaging portion 24 </ b> C of the lens frame 24, and this cam pin 26 is engaged with a cam groove 20 </ b> C formed on the inner peripheral surface of the focus ring 20. Therefore, when the focus ring 20 is rotated, the intersection position of the cam groove 20C and the rectilinear groove 12C is displaced in the optical axis P direction, and the lens frame 24 and the focus lens (group) 22 are moved along with the displacement of the intersection position. Move in the direction of the optical axis P. As a result, the focus lens (group) 22 moves in the direction of the optical axis P, and focus adjustment is performed. A plurality of engaging portions including an engaging portion 24C of the lens frame 24, a cam pin 26, a cam groove 20C of the focus ring 20, and a rectilinear groove 12C of the lens barrel body 12 are provided in order to move the lens frame 24 stably. Preferably, it is usually provided at three places where the circumference is divided into three equal parts.

  The focus ring 20 has a screw hole 20A penetrating from the outer peripheral surface to the inner peripheral surface, and a knob 28 is screwed into the screw hole 20A. The operator can also rotate the focus ring 20 using this knob 28. Further, the focus ring 20 can be fixed at a desired focus adjustment position by screwing the knob 28 and pressing the tip thereof against the outer peripheral surface of the large diameter portion 12A of the lens barrel body 12.

  A zoom lens (group) 32 held by a lens frame 34 is disposed on the optical axis P inside the small diameter portion 12B of the lens barrel body 12. An engaging portion 34D protrudes from the outer peripheral surface of the lens frame 34. The engaging portion 34D is engaged with a rectilinear groove 12D formed in the optical axis P direction on the small diameter portion 12B. Thereby, the lens frame 34 and the zoom lens (group) 32 are supported movably in the optical axis P direction.

  A cam pin 36 protrudes from the engaging portion 34 </ b> D of the lens frame 34, and this cam pin 36 is engaged with a cam groove 30 </ b> D formed on the inner peripheral surface of the zoom ring 30. Therefore, when the zoom ring 30 is rotated, the intersection position of the cam groove 30D and the rectilinear groove 12D is displaced in the optical axis P direction, and the lens frame 34 moves in the optical axis P direction according to the displacement of the intersection position. . As a result, the zoom lens 32 moves in the direction of the optical axis P, and the focal length (zoom angle of view) is adjusted. A plurality of engaging portions including an engaging portion 34D of the lens frame 34, a cam pin 36, a cam groove 30D of the zoom ring 30, and a rectilinear groove 12D of the lens barrel body 12 are provided in order to move the lens frame 34 stably. Preferably, it is usually provided at three places where the circumference is divided into three equal parts.

  Further, the zoom ring 30 is formed with a screw hole 30A penetrating from the outer peripheral surface to the inner peripheral surface, and a knob 38 is screwed into the screw hole 30A. The operator can also rotate the focus ring 30 using the knob 38. Further, the zoom ring 30 can be fixed at a desired focal length adjustment position by screwing the knob 38 and pressing the tip thereof against the outer peripheral surface of the small-diameter portion 12B of the lens barrel body 12.

  As shown in FIG. 2, the diaphragm device 16 has a plate-like casing 60, and the casing 60 is inserted into the lens barrel body 12 and attached. Specifically, a slit-shaped opening 12E is formed in the circumferential direction at a boundary portion between the large-diameter portion 12A and the small-diameter portion 12B of the lens barrel body 12, and a plate-like shape is formed in the slit-shaped opening 12E. The casing 60 is inserted and attached in a direction orthogonal to the optical axis P. The casing 60 and the lens barrel body 12 are connected by a snap-in structure (not shown). That is, the casing 60 is provided with an elastically deformable arm, and an engaging claw is formed at the tip of the arm. Then, the engaging claw is fitted into the groove of the lens barrel body 12, whereby the casing 60 of the diaphragm device 16 is mounted on the lens barrel body 12. In addition, the connection method of the diaphragm | throttle device 16 and the lens barrel main body 12 is not limited to a snap-in structure, It is also possible to select other connection methods, such as screwing by a screw.

  A circular opening 60 </ b> A is formed in the casing 60, and the opening 60 </ b> A is disposed on the optical axis P when the casing 60 is attached to the lens barrel body 12. In addition, two diaphragm blades (not shown) are provided in the casing 60, one diaphragm blade is disposed above the opening 60A, and the other diaphragm blade is disposed below the opening 60B. . Each diaphragm blade is supported so as to be slidable in the vertical direction, and each diaphragm blade is moved in the vertical direction by driving a drive unit (such as an iris meter) 62 attached to the lower end of the casing 60. . The diaphragm blades disposed above the opening 60A move downward and the diaphragm blades disposed below the opening 60A move upward, so that the opening 60A is closed by the two diaphragm blades, and the subject light Will not pass. Further, by driving the driving unit 62 to move the upper diaphragm blades upward and the lower diaphragm blades downward, the two diaphragm blades are retracted from the opening 60A, and the entire opening 60A is moved to the subject. The light can pass through. The configuration of the diaphragm device 16 is not limited to that described above, and an iris diaphragm mechanism or the like may be used.

  As shown in FIG. 2, the diaphragm device 16 is provided with rotation restricting portions 64 and 64, and the rotation restricting portions 64 and 64 restrict the rotation of the operation ring such as the focus ring 20 and the zoom ring 30. Is done. The rotation restricting portions 64 and 64 are formed at the connecting portion between the casing 60 and the driving portion 62 of the expansion device 16 and projecting outward from both sides. Each rotation restricting portion 64 includes a focus restricting portion 64B on the distal end side and a zoom restricting portion 64A on the proximal end side.

  The diaphragm device 16 configured as described above is mounted by attaching the focus ring 20 and the zoom ring 30 to the lens barrel body 12 and then inserting the focus ring 20 and the zoom ring 30 into the opening 12E of the lens barrel body 12. Thereby, the rotation restricting portion 64 of the diaphragm device 16 is disposed at a predetermined position, and the rotation restricting portion 64 restricts the rotation of the focus ring 20 and the rotation of the zoom ring 30. That is, the rotation of the focus ring 20 is restricted by the focus restricting portion 64B, and the rotation of the zoom ring 30 is restricted by the zoom restricting portion 64A. The rotation restricting portions 64 and 64 are also used as positioning means for the diaphragm device 16 with respect to the lens barrel body 12 when the diaphragm device 16 is inserted into the lens barrel body 12 and attached.

  Hereinafter, the rotation restriction of the focus ring 20 will be described with reference to FIGS. 2 and 3A to 3C. 3 (A) to 3 (C) show a cross section taken along line 3-3 in FIG. 1, and FIG. 3 (A) shows a state where there is no rotation operation, and FIG. 3 (B) and FIG. C) shows a state in which each is controlled by turning in the opposite direction.

  As shown in FIG. 2, the focus ring 20 has a part of the end surface on the base end side (specifically, approximately 2/3 on the upper side) protruding, and stepped portions 20D and 20D at both ends of the protruding portion. Is formed. The step portions 20D and 20D are arranged on the small diameter portion 12B so as to protrude from the base end of the large diameter portion 12A of the lens barrel body 12 when the focus ring 20 is attached to the lens barrel body 12. Further, as shown in FIG. 3A, the stepped portions 20D and 20D have inclined surfaces 20E and 20E that are cut obliquely, and the inclined surfaces 20E are shown in FIG. 3B or 3C. When the focus ring 20 is rotated as shown in FIG. 6, the surface is brought into contact with the focus restricting portion 64B.

  When the focus ring 20 configured as described above is rotated counterclockwise from the state shown in FIG. 3A, the inclined surface 20E of the stepped portion 20D is moved to the focus restricting portion as shown in FIG. 3B. Abutting on 64B, the rotation operation of the focus ring 20 is restricted. When the focus ring 20 is rotated clockwise from the state shown in FIG. 3A, the inclined surface 20E of the step 20D on the opposite side is brought into contact with the focus restricting portion 64B as shown in FIG. 3C. In contact, the rotation operation of the focus ring 20 is restricted. Thereby, the focus ring 20 can be set to an accurate operation range, and the focus operation can be performed accurately.

  Next, the rotation restriction of the zoom ring 30 will be described with reference to FIGS. 2 and 4A to 4C. 4 (A) to 4 (C) show a cross section taken along line 4-4 of FIG. 1, and FIG. 4 (A) shows a state where there is no rotation operation, and FIG. 4 (B) and FIG. C) shows a state in which each is controlled by turning in the opposite direction.

  As shown in FIG. 4A, the zoom ring 30 is provided with a protrusion 66 protruding from the outer peripheral surface. The protrusion 66 is made of, for example, resin and is formed integrally with the zoom ring 30. Further, the protrusion 66 is preferably formed in a range smaller than the focus ring 20 as shown in FIG. Further, the protrusion 66 has contact surfaces 66A and 66A that come into surface contact with the zoom restricting portions 64A and 64A when the zoom ring 30 is rotated as shown in FIG. 4B or 4C. Is formed.

  When the zoom ring 30 configured as described above is rotated counterclockwise from the state shown in FIG. 4A, the projection 66 abuts against the zoom restricting portion 64A as shown in FIG. 4B. The rotation operation of the zoom ring 30 is restricted. When the zoom ring 30 is rotated clockwise from the state shown in FIG. 4A, the projection 66 comes into contact with the zoom restricting portion 64A as shown in FIG. Rotation operation is restricted. Thereby, the zoom ring 30 can be set to an accurate operation range, and the zoom operation can be performed accurately.

  On the other hand, the connecting member 14 shown in FIG. 1 is a member for connecting the lens barrel body 12 and the camera 18 and is formed in a substantially cylindrical shape. A concave groove 40 is formed around the outer peripheral surface of the connecting member 14, and a bayonet claw of the camera 18 is engaged with and connected to the groove 40. The method for connecting the camera 18 and the connecting member 14 is not particularly limited, and the camera 18 may be screwed to the connecting member 14. The camera 18 may be a built-in type in which the CCD and the substrate are exposed. In this case, a concave portion is formed in the connecting member 14 and the CCD of the camera 18 is fitted in the concave portion. The camera 18 is screwed.

  The connecting member 14 of the present embodiment is connected to the proximal end of the small diameter portion 12B of the lens barrel body 12 using a snap-in mechanism. Hereinafter, the connection structure will be described with reference to FIGS. 5 (A) to 5 (C), FIG. 6, and FIGS. 7 (A) to 7 (D).

  5A is a cross-sectional view taken along line 5-5 in FIG. 1, FIG. 5B shows only the lens barrel body 12 in FIG. 5A, and FIG. Is shown. FIG. 6 is a perspective view showing a coupling mechanism between the coupling member 14 and the lens barrel 12. FIG. 7A to FIG. 7D are explanatory diagrams showing a connection method, and are schematic views viewed from the optical axis P side.

  As shown in FIG. 6, a support portion 42 is formed to protrude in the optical axis P direction on the end surface 48 on the proximal end side of the lens barrel body 12, and an arm 44 is provided at the tip of the support portion 42. Yes. The arm 44 and the support part 42 are integrally formed with the lens barrel body 12 by resin, and the arm 44 extends in the circumferential direction from the tip of the support part 42. The arm 44 is formed with a strength that can be sufficiently elastically deformed. For example, the arm 44 can be elastically deformed in a direction away from the end surface 48 of the lens barrel body 12.

  The arm 44 is formed with a protrusion (claw) 46 protruding from the surface on the lens barrel body 12 side. The protrusion 46 is sized to be engaged with a through hole 56 described later. Further, as shown in FIG. 7A, the protruding portion 46 is chamfered at the tip side to form an inclined surface 46A, and is not caught by the engaging portion 54 when the protruding portion 46 is moved in the circumferential direction. There is no such thing.

  The arm 44 is arranged at a distance D1 with respect to the end surface 48 of the lens barrel body 12. Moreover, the arm 44 is arrange | positioned in the position divided into 3 equal to the circumferential direction, as shown to FIG. 5 (B).

  On the other hand, as shown in FIG. 6, the connecting member 14 is formed with a convex portion 52 protruding from the base end of the inner peripheral surface over the entire circumference. Further, an engaging portion 54 is formed to protrude from the inner peripheral surface of the connecting member 14. The engaging portion 54 is formed continuously from the convex portion 52 and has a sufficient strength not to be deformed. The engaging portion 54 is formed in the circumferential direction, and its thickness T1 (see FIG. 7A) is formed with the same dimension as the distance D1 between the arm 44 and the end surface 48 described above. Further, the distance D2 between the engaging portion 54 and the convex portion 52 is formed larger than the thickness T2 of the arm 44, and the arm 44 can be inserted between the engaging portion 54 and the convex portion 52. Yes. Note that an opening 58 is formed between the engaging portion 54 and the convex portion 52 so as to penetrate the inner peripheral surface and the outer peripheral surface. Therefore, it can be visually recognized from the outside that the protrusion 46 of the arm 44 is engaged with a through hole 56 described later.

  As shown in FIG. 5C, the engaging portions 54 are provided at three locations, and are arranged at positions equally divided into three in the circumferential direction. Each engaging portion 54 is formed with a through hole 56 in the optical axis P direction so that the projection 46 of the arm 44 is engaged.

  Next, the operation of the lens barrel 10 configured as described above will be described with reference to FIGS. 7 (A) to 7 (D).

  When fixing the connecting member 14 to the lens barrel body 12, first, the connecting member 14 shown in FIG. Then, as shown in FIG. 7B, the end surface 48 of the lens barrel body 12 is pressed against the engaging portion 54 of the connecting member 14.

  Next, in this state, the connecting member 14 is rotated with respect to the lens barrel body 12. Thereby, as shown in FIG. 7C, the tip of the arm 44 of the lens barrel body 12 is inserted between the engaging portion 54 and the convex portion 52. At this time, the arm 44 is inserted while being elastically deformed outward by the amount of the protrusion 46 at the tip.

  When the rotation of the connecting member 14 is further advanced, the projection 46 of the arm 44 falls into the through hole 56 of the engaging portion 54 with a noise as shown in FIG. Then, the protruding portion 46 of the arm 44 is engaged with the through hole 56 of the engaging portion 54 by the elastic force of the arm 44 itself, and the connecting member 14 is fixed to the lens barrel body 12.

  Thus, according to the lens barrel 10 of the present embodiment, the barrel body 12 and the connecting member 14 are connected by the snap-in mechanism. That is, the projection 46 is engaged with the through hole 56 by the elastic force of the arm 44, and the lens barrel body 12 and the connecting member 14 are connected. When the connection is performed in this way, the connection is always performed with a constant force due to the elastic force of the arm 44, so that it is possible to prevent the connected lens barrel body 12 from being distorted.

  Further, according to the present embodiment, the arm 44 of the snap-in mechanism is integrally formed with the lens barrel body 12 and the engaging portion 54 is integrally formed with the connecting member 14, so that it is necessary to use a fixing tool such as a screw separately. There is no. Furthermore, according to the present embodiment, since the connecting member 14 can be connected to the lens barrel body 12 simply by rotating it, a tool such as a screwdriver is unnecessary. Therefore, according to this Embodiment, the lens barrel main body 12 and the connection member 14 can be connected easily and at low cost.

  Furthermore, in this embodiment, since the connecting member 14 is rotated to be engaged with the lens barrel main body 12, the connecting member 14 and the lens barrel main body 12 can be connected in a state of being positioned in the optical axis P direction. it can. That is, the protrusion 46 of the arm 44 is inserted into the through-hole of the engaging portion 54 while keeping the end surface 48 of the lens barrel body 12 in contact with the engaging portion 54 of the connecting member 14 and being positioned in the optical axis P direction. 56 can be engaged with each other. In particular, in the present embodiment, the projecting portion 46 of the arm 44 is formed on the end surface 48 side of the lens barrel body 12 so that the engaging portion 54 is sandwiched between the arm 44 and the end surface 48. A contact state with the engaging portion 54 can always be ensured. Therefore, according to the present embodiment, since the connecting member 14 and the lens barrel body 12 can be positioned and connected in the direction of the optical axis P, the optical performance can be improved.

  In the above-described embodiment, the shape and number of the projections 46 of the arm 44 and the through holes 56 of the engagement unit 54 are not particularly limited, and the projections 46 and the through holes 56 are engaged. Any configuration may be used. For example, a groove may be formed instead of the through hole 56 to engage the protrusion 46.

  In the above-described embodiment, the protrusion 46 is formed at the tip of the arm 44 and the through hole 56 is formed in the engaging portion 54 of the connecting member 14. That is, a through hole may be formed at the tip of the arm 44 and a protrusion that engages with the through hole may be provided in the engaging portion 54. Further, an arm may be formed on the connecting member 14, and an engaging portion may be formed on the lens barrel body 12.

Sectional drawing which shows the structure of the lens barrel which concerns on this invention Exploded perspective view of lens barrel Sectional view for explaining the rotation restriction of the focus ring Sectional drawing for demonstrating rotation restrictions of a zoom ring Sectional drawing which follows the 5-5 line of FIG. Perspective view showing the coupling mechanism Explanatory drawing which shows connection operation | movement with a lens barrel main body and a connection member.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Lens barrel, 12 ... Lens barrel main body, 14 ... Connecting member, 16 ... Aperture device, 18 ... Camera, 20 ... Focus ring, 20D ... Step part, 22 ... Focus lens, 24 ... Lens frame, 30 ... Zoom ring 32 ... Zoom lens, 34 ... Lens frame, 42 ... Support part, 44 ... Arm, 46 ... Projection part, 54 ... Engagement part, 56 ... Through-hole

Claims (1)

In a lens barrel having a lens barrel body and a connecting member fixed to the lens barrel body and connected to a camera,
One of the first cylindrical members formed of the lens barrel body or the connecting member extends in the circumferential direction from the front end of a support portion that protrudes from the end surface of the first cylindrical member in the optical axis direction. Provided with an elastically deformable arm,
The other second cylindrical member made of the lens barrel body or the connecting member is provided with an engaging portion formed in the circumferential direction on the inner peripheral surface of the second cylindrical member ,
The arm has a convex portion or a concave portion formed on the end surface side of the first cylindrical member, and the engaging portion has a concave portion or a convex portion corresponding to the convex portion or the concave portion of the arm. Formed,
By engaging the convex portion or concave portion of the arm with the concave portion or convex portion of the engaging portion in a state where the engaging portion is sandwiched between the end surface of the first cylindrical member and the arm, lens barrel characterized that you connect the first and second tubular members.

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