JP4092755B2 - Lens accessories - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens accessory used in, for example, a still camera, a video camera, a telescope, a binocular, and the like, and in particular, a lens accessory such as a lens cap or a lens hood attached to the tip of a lens barrel of a camera as an accessory mounting portion. About.
[0002]
[Prior art]
For example, in a camera, a lens cap is often attached as a lens accessory to be attached to the tip of a lens barrel in order to protect a photographing lens. Various types of lens caps have been known in the past. Among them, the structure shown in FIG. 6, for example, is assumed to be simple in structure, quick to attach and detach, and less likely to drop off. Has been proposed.
[0003]
As shown in FIG. 6, the lens cap 1 includes a lens cap body 2 that serves as a lid that protects the surface of the photographing lens by covering the tip of a lens barrel (not shown). The lens cap body 2 has a substantially annular shape and includes an annular portion 2a that is fitted into the inner peripheral surface of the tip portion of the lens barrel and a lid portion 2b that covers the front surface of the lens.
A pair of annular notches 2c and 2c are formed in the axially symmetric portion of the annular portion 2a, and have an elastic force in a direction protruding outward from the notches 2c and 2c of these annular portions. An elastic member 4 having knob portions 3 and 3 is held on the inner peripheral surface of the annular portion 2 a of the lens cap body 2.
[0004]
The elastic ring member 4 is formed in a direction perpendicular to the axis (optical axis) of the lens cap 1 against the elastic force of the elastic ring member 4 on the elastic claws 3a and 3a provided on the knob portions 3 and 3 (arrows in the figure). (A direction) is pressed from the outside, and the annular portion 2a is fitted into the accessory mounting portion on the distal end side of the lens barrel to release the pressing force, thereby engaging the accessory mounting portion with the knob portions 3 and 3. The claw portions 3a, 3a are configured to be able to fix the lens cap 1 to the lens barrel by urging the claw portions 3a, 3a in a direction (arrow B direction in the drawing) perpendicular to the axis.
[0005]
Such removal of the lens cap 1 is performed by pressing the knobs 3 and 3 described above from the outside in the radial direction (in the direction of arrow A in the figure), and using the elasticity of the engaging claws 3a and 3a. It can be removed by moving in an orthogonal direction (arrow B direction in the figure) and releasing the locked state to the lens barrel.
[0006]
[Problems to be solved by the invention]
In the conventional lens cap 1 having such a structure, the lens cap body 2 and the elastic member 4 are integrally assembled so as not to be separated from each other, so that the lens cap body 2 has a part of the inner peripheral surface of the annular portion 2a. Undercut portions 5a to 5d are formed. And, at the time of assembling, a structure is generally adopted in which a part of the elastic member 4 is fitted into the undercut portions 5a to 5d while being bent.
[0007]
However, the lens cap body 2 and the elastic member 4 are usually formed by molding with a synthetic resin material. As described above, if there is a portion by the undercut portions 5a to 5d, The mold division becomes complicated, the manufacturing cost increases, and there are many problems in terms of mass productivity.
Moreover, since it is necessary to bend the elastic member 4 at the time of an assembly as mentioned above, there also exists a problem that an assembly is complicated.
[0008]
The present invention has been made in view of such circumstances, and in forming a lens accessory composed of an accessory body and an elastic member, the undercut portion, which has been a problem from the conventional molding, is eliminated, and the moldability is improved. It is an object of the present invention to obtain a lens accessory that eliminates problems in terms of manufacturing cost and mass productivity and is easy to assemble.
[0009]
[Means for Solving the Problems]
In order to meet such an object, the lens accessory according to the present invention has an annular portion that is attached to the accessory attachment portion of the lens barrel, and a notch is formed in the side edge portion on the accessory attachment portion side. An accessory main body and a pair of knobs that are assembled and held inside the annular portion of the accessory main body and biased in the direction of protruding outward through the notch, are provided on a part thereof. And an annular elastic member for fixing the accessory body by pressing the claw portion against the accessory mounting portion from the inside in the radial direction. Then, at least one locking convex portion is protruded from a part of the notch so as to face the notch, and the elastic convex portion is formed in the notch by the locking convex portion. The knob portion of the member is assembled and held.
[0010]
Further, the lens accessory according to the present invention is formed by forming a notch groove in a part of the elastic member for engaging and passing the engaging convex portion when the elastic member is assembled to the accessory body. is there. Furthermore, the lens accessory according to the present invention has a notch groove for engaging and passing the engaging protrusion when the elastic member is assembled to the accessory body in the assembled state of the elastic member to the accessory body. It is formed at a position where it does not engage with the locking projection. In the lens accessory according to the present invention, a second convex portion is provided between the accessory body and the elastic member to restrict the movement of the knob portion of the elastic member within the notch of the accessory body in the assembled state. Is.
[0011]
Furthermore, in the lens accessory according to the present invention, a pair of the notches are provided at symmetrical positions around an axis passing through the central portion of the annular portion. In the lens accessory according to the present invention, the locking convex portion is provided in a portion near the side edge on the accessory mounting portion side of the side wall surface forming the notch, and the accessory main body has a notch. It is a part, and a notch part for die cutting is formed on the side edge part opposite to the accessory attaching part. Further, in the lens accessory according to the present invention, an axial gap is formed between the locking projection and the accessory mounting portion in the notch and the side edge on the opposite side, and the elastic member The elastic member is assembled and held on the accessory body in a state in which the knob portion is restricted from moving in the axial direction.
[0012]
According to the present invention, since there is no undercut portion in forming the locking convex portion for holding the elastic member in the accessory body, the molding die can be easily manufactured and the manufacturing cost can be reduced. Can do.
[0013]
In addition, according to the present invention, the elastic member can be assembled to the accessory body with a simple operation of fitting the notch groove into the locking convex portion, and the workability during the assembly is improved. The elastic member can be assembled and held on the accessory body in a state in which a required movement is ensured.
[0014]
Lens accessories include, for example, a lens cap and a lens hood, but are not limited thereto.
Although the accessory main body and the elastic member constituting the lens accessory are integrally formed of a synthetic resin material and assembled in a required state, the present invention is not limited to this.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 to 3 show one embodiment in which the lens accessory according to the present invention is applied to a lens cap. In these drawings, the same or corresponding parts as those in FIG. Detailed description will be omitted.
[0016]
FIGS. 1A and 1B show a lens cap body 2 constituting a lens cap 1. The lens cap body 2 includes an annular portion 2a fitted on the inner peripheral surface of the tip of the lens barrel and a lens front surface. A cover 2b is formed, and knobs 3 and 3 of an elastic member 4 to be described later are projected outward at an axially symmetric position centered on an axis (optical axis) passing through the center of the annular portion 2a. For this purpose, notches 2c and 2c are formed in the annular portion .
Note that the outer diameter of the annular portion 2a is slightly smaller than the outer diameter of the lid portion 2b.
[0017]
Notches 2d and 2d are formed on both sides of the annular notches 2c and 2c on the surface including the lid 2b. And at the positions spaced apart from the lid portion 2b in the axial direction of the annular portion 2a on both sides of the notches 2c, 2c in the annular portion 2a, there are four locking projections 11 of the annular portion. It protrudes so as to face the notches 2c and 2c.
The gap between the locking convex portion 11 and the lid portion 2b forms a gap for holding and holding knob portions 3 and 3 of the elastic member 4 to be described later from both sides in the axial direction.
[0018]
The lens cap body 2 having the above-described shape can be easily obtained by a pair of molds from both sides in the axial direction including the notches 2c and 2c and the notches 2d and 2d. Can be molded. Even if the locking convex portion 11 is provided at a position spaced apart from the lid portion 2b in the axial direction of the annular portion 2a, the annular portions notches 2c and 2c are formed on the surface including the lid portion 2b. Since the notches 2d and 2d are formed on both side portions, the undercut portion is not formed.
[0019]
2 (a) and 2 (b) show an elastic member 4 having a substantially annular shape as a whole, and the notches 2c and 2c are provided at axially symmetrical positions around the axis of the elastic member 4. Knob portions 3 and 3 are formed so as to protrude to the outside of the annular portion 2a.
[0020]
Pressing portions 3b and 3b are formed at the outer ends of the knob portions 3 and 3, and one side of the pressing portions 3b and 3b in the axial direction is inside (a portion closer to the inside in the radial direction). In addition, elastic claw portions 3a and 3a are formed which engage with and engage with the inner peripheral surface (accessory mounting portion) of the tip of the lens barrel.
Although not shown, these elastic claws 3a, 3a are formed in a concavo-convex shape so as to mesh with the accessory mounting portion.
[0021]
The elastic member 4 is made of an elastic material (for example, a synthetic resin material). By pressing the pressing portions 3b and 3b of the knob portions 3 and 3 radially outward from the outside, it is configured to be elastically deformable radially inward along with the meshing engagement claws 3a and 3a. The entire lens cap 1 can be attached to and detached from the accessory mounting portion.
[0022]
In such an elastic member 4, notches corresponding to the engaging convex portions 11 provided on the lens cap body 2 are formed on both sides in the circumferential direction of the knob portions 3 and 3 and on the radially inner side. Grooves 12 are formed at four locations.
As shown in FIG. 3A, these notch grooves 12 are formed so as to be located closer to the inner side in the radial direction than the protrusion 11 for locking when the lens cap 1 is assembled.
[0023]
FIG. 3 shows a state in which the lens cap body 2 shown in FIG. 1 and the elastic member 4 shown in FIG. 2 are assembled. The elastic member 4 is formed by the four locking projections 11 of the lens cap body 2. Is restricted from moving in the axial direction.
The elastic member 4 is assembled and held by fitting the knob portions 3 and 3 into a gap between the lid portion 2a on the lens cap body 2 side and the locking convex portion 11. Such an assembled state can be obtained by the following procedure.
[0024]
That is, the assembling procedure is performed as shown in FIGS. As shown in FIGS. 1 and 2, the elastic member 4 is formed with notched grooves 12 for allowing the locking projections 11 to pass through. The positions of these grooves 12 are shown in FIG. 3. As shown, it is closer to the inside in the radial direction than the locking projection 11 during assembly.
Of course, any position may be used as long as the movement of the knobs 3 and 3 of the elastic member 4 is not hindered, and it is not always necessary to be parallel to the axis (optical axis).
[0025]
As shown in FIG. 4, first, according to the arrow a in the figure, the locking projection 11 corresponding to the notch groove 12 of one of the knobs 3 and 3 is positioned, and the elastic member 4 is moved in the direction of the arrow X. Proceed. After the knob portion 3 of the elastic member 4 is assembled corresponding to the lens cap body 2 side, the locking convex portion 11 is aligned with the notch groove 12 in the knob portion 3 on the opposite side. At this time, the notch groove 12 is slightly misaligned with the locking projection 11, but this uses the elastic force of the elastic member 4 to make it extend in the direction of the arrow Y, and the arrow Z It is only necessary to proceed in the direction so as to be assembled in the same procedure as that of the first one.
[0026]
Then, when the tensile force applied to the elastic member 4 described above is removed, an assembled state as shown in FIGS. 3A and 3B can be obtained. In such an assembled state, the elastic member 4 can be reliably assembled and held to the lens cap body 2. Further, when the knob portions 3 and 3 of the elastic member 4 are pressed and the engaging claws 3a and 3a are engaged with and engaged with the accessory mounting portion of the lens barrel, the lens cap 1 is mounted in a required state. Can do. If it is operated in reverse, it can be easily removed.
[0027]
FIG. 5 shows the lens cap 1 assembled as described above in order to limit the movement of the elastic member 4 in the direction of the arrow P in the figure relative to the lens cap main body 2 and to prevent the movement (so-called rattling). This is a case where the limiting means is provided.
That is, when the knob portions 3 and 3 in the elastic member 4 move more than necessary, the locking convex portion 11 faces the notch groove 12 and drops off, or the elastic member 4 moves freely.
[0028]
For this reason, as shown in FIGS. 5A and 5B, a recess 21 is provided on the surface of the elastic member 4 facing the lid 2b of the knobs 3 and 3, and the lid 2b side corresponding to this is provided. A restricting convex portion 22 is provided. The convex portion 22 may be formed in a shape having a tapered surface so that it can be easily fitted as shown in FIG.
[0029]
In this way, by assembling the elastic member 4 to the lens cap body 2, it is possible to limit movement more than necessary and to prevent idle movement. When such a structure is adopted, the convex portion 22 may come into contact with a part of the elastic member 4 at the time of assembling, but generally the size of the convex portion 22 can be absorbed by the bending of each member. If this is the case, the knob portions 3 and 3 can get over the convex portion 22, and there is no particular problem. Of course, the shape of the convex portion 22 is not limited to the illustrated shape, and an appropriate shape can be adopted as long as it does not hinder the assembly.
[0030]
Note that the present invention is not limited to the structure described in the above-described embodiment, and it goes without saying that the shape and structure of each part can be appropriately modified and changed.
For example, the case where the accessory main body (lens cap main body 2) and the elastic member 4 constituting the lens accessory are integrally formed of a synthetic resin material and assembled in a required state has been described. It is possible.
[0031]
In the above-described embodiment, a pair, i.e., two knob portions 3 are provided at positions symmetrical to the optical axis. However, the present invention is not limited to this, and one knob portion 3 may be provided. When there is one knob portion 3, a screw structure that meshes with the accessory mounting portion on the inner peripheral surface of the distal end portion of the lens barrel is formed at a position outside the annular portion 2a symmetrical to the knob portion 3 with respect to the optical axis. It is necessary to keep it.
[0032]
Further, in the above-described embodiment, the case where the present invention is applied to the lens cap 1 that protects the photographing lens by detachably attaching the accessory mounting portion to the distal end portion of the lens barrel of the still camera has been described. However, the present invention is not limited to this, and the present invention can be applied to various filters, lens hoods, and filter holders that are attached to an accessory mounting cylindrical portion such as the tip of the lens barrel 6 and used to improve image quality.
[0033]
That is, although the lens cap 1 is exemplified in the above-described embodiment, the lens cap 1 includes an accessory body having an annular portion like the lens cap body 2 and an elastic member 4 held on the inside thereof, and the elastic member 4. As long as the knobs 3 and 3 projecting outward from the base plate 3 are elastically deformed in the radial direction, any structure may be used. For example, in order to use it for a lens hood which is an accessory for a lens, the accessory constituent member may be configured to prevent light passing through the lens from being applied and can be appropriately applied.
[0034]
【The invention's effect】
As described above, according to the lens accessory according to the present invention, since there is no undercut portion in the accessory main body, the molding die can be easily manufactured, and the manufacturing cost can be reduced.
[0035]
Further, according to the present invention, the assembly of the elastic member to the accessory body can be performed by a simple operation of fitting the notch groove into the locking convex portion, so that the workability at the time of assembly is improved. Therefore, it is possible to provide a lens accessory inexpensively and easily.
[Brief description of the drawings]
1A and 1B show an embodiment in which a lens accessory according to the present invention is applied to a lens cap, wherein FIG. 1A is a rear view of a lens cap body, and FIG.
2A and 2B show an elastic member assembled to the lens cap body of FIG. 1, wherein FIG. 2A is a rear view thereof, and FIG. 2B is a side view thereof.
3 shows a state where the lens cap main body of FIG. 1 and the elastic member of FIG. 2 are assembled, (a) is a rear view thereof, (b) is a side sectional view, and (c) is a knob portion which is a main part. It is a side view of a built-in part.
4A and 4B are views for explaining an assembled state of the lens cap in FIG. 3, where FIG. 4A is an exploded view seen from the back side, and FIG. 4B is an exploded view seen from the side surface side.
5A and 5B show another embodiment of the present invention, where FIG. 5A is a rear view, and FIG. 5B is a side view.
FIG. 6 is a rear view for explaining a lens cap as a conventional lens accessory.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Lens cap (lens accessory), 2 ... Lens cap main body, 2a ... Annular part (annular part), 2b ... Lid part, 2c ... Notch, 2d ... Notch part for die cutting, 3 ... Knob part, 3a ... engaging claw part, 3b ... pressing part, 4 ... elastic member, 4a ... annular part, 11 ... locking convex part, 12 ... notch groove, 21 ... concave part, 22 ... limiting convex part.

Claims (4)

An accessory body having a lid and an annular part attached to the accessory attachment part of the lens barrel, and a notch is formed in a side edge of the annular part on the accessory attachment part side;
The accessory main body has a pair of knob portions that are assembled and held inside the annular portion of the accessory body and biased outwardly through the notches, and provided on a part of the knob portions. An annular elastic member that fixes the accessory body to the accessory mounting portion by pressing the engaging claw portion against the accessory mounting portion from the inside in the radial direction;
A locking convex part protruding from a part of the notch of the annular part so as to face the notch,
On the surface including the lid portion, a die-cutting notch portion in which a notch is formed at a position facing the locking convex portion,
The elastic member has a notch groove for engaging and passing the elastic protrusion when the elastic member is assembled to the accessory body in the assembled state of the elastic member to the accessory body. Formed at a position closer to the inner side in the radial direction of the accessory body than the locking convex part of the part,
An accessory for a lens, wherein the knob portion of the elastic member is assembled and held in a gap formed in the notch of the annular portion by the locking convex portion. In accessory according to claim 1 Symbol placement of the lens,
A lens accessory characterized in that a second convex portion is provided between the accessory main body and the elastic member to restrict movement of the knob portion of the elastic member in the notch of the annular portion in the assembled state. . The lens accessory according to claim 1,
An accessory for a lens, wherein a pair of notches in the annular portion are provided at symmetrical positions around an axis passing through a central portion of the annular portion. The lens accessory according to any one of claims 1 to 3 ,
The locking convex portion forms an axial gap between the accessory mounting portion in the notch of the annular portion and the side edge portion on the opposite side, and the knob portion of the elastic member is in the axial direction. An accessory for a lens, wherein the elastic member is assembled and held in the accessory body in a state where movement is restricted.

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