JP2005004111A - Lens cap - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To propose an inexpensive lens cap attached to the flower-shaped edge part of a lens barrel with easy operation. <P>SOLUTION: The lens cap 1 is a resin molding, and is equipped with a cylindrical barrel part 2, an end plate part 3 sealing one end of the barrel part 2, and an annular insertion groove 4 formed on the inner peripheral surface side of the barrel part 2. By fitting the aperture end 5 of the lens cap 1 to the edge of the lens barrel 6 and pushing the lens cap 1 into the lens barrel 6, the edge surface 7a of the lens barrel 6 is inserted in the groove 4 and the lens cap 1 is easily attached to the edge of the lens barrel 6 through one action. Since the flower-shaped edge part 7 of the lens barrel 6 is covered with the lens cap 1, it is surely protected, and also dust and dirt are prevented from entering from the outside. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens cap attached to a camera and a lens cap that covers a front end opening of a lens hood. More specifically, the present invention relates to a lens cap suitable for a lens barrel or a lens hood for an ultra-wide-angle lens having a flower-shaped tip surface.
[0002]
[Prior art]
A lens barrel or lens hood for a super-wide-angle lens having a large angle of view has a petal-like shape or a flower-like contour shape so that vignetting is not caused by the tip portion (filter screw portion). For this reason, as a lens cap that covers such a lens barrel or lens hood, a general petri dish cannot be used, and a leather or cloth covered lens cap is used. Such a cover-type lens cap is, for example, attached to a leather or cloth lens cap body to which a disk-shaped reinforcing member is attached, as shown in the following patent document, and tightened. It is configured to be fixed to the lens barrel side by tightening with a tool.
[0003]
[Patent Literature]
Japanese Patent Laid-Open No. 2002-244179 [0004]
[Problems to be solved by the invention]
However, the conventional lens cap for covering the lens barrel or the lens hood having a flower tip has the following problems.
[0005]
(1) Since it is composed of a plurality of parts such as a disk-shaped reinforcing member, a lens cap body made of leather, a fastening string, a fastener, etc., the manufacturing cost is high.
(2) The opening of the flower-shaped tip of a lens barrel with a lens cap is only protected by a disk-shaped reinforcing member. Therefore, the outer peripheral surface of the tip portion such as a lens barrel covered with a lens cap made of leather or cloth cannot be protected from impact, and the impact resistance is poor.
(3) The straps and fasteners that fix the lens cap body to a lens barrel or the like are liable to deteriorate due to changes over time due to problems in material properties and cannot satisfy the functions.
(4) Since the disk-shaped reinforcing member is only pressed against the flower-shaped tip of the lens barrel, the gap between the lens cap body and the outer periphery of the lens barrel and the gap between the flower-shaped tip and the reinforcing member are externally provided. Therefore, there is a risk that dust or dust may enter and adhere to the lens surface. There is also a risk that dust, dust, and the like peeled off from the leather or cloth lens cap body may adhere to the lens surface.
(5) Since the lens cap body placed on the lens tip of the lens barrel is tightened with a fastening string or the like to form a wrinkle or the like, the appearance when the lens cap is attached is inferior.
(6) The lens cap body made of leather or cloth easily absorbs moisture, and the absorbed moisture may cause mold on each surface of the lens.
(7) The disc-shaped reinforcing member pressed against the flower-shaped tip of the lens barrel by the lens cap body tends to be inclined, unlike when pressed against a flat end surface.
[0006]
An object of the present invention is to propose a lens cap capable of solving such conventional problems.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the lens cap of the present invention is:
A tubular body,
An end plate portion sealing one end of the cylindrical body,
An insertion groove formed inside the cylindrical body,
Due to the engagement force between the insertion groove and the lens barrel or the front end portion of the lens hood inserted into the insertion groove from the opening end of the cylindrical body portion, the front end portion of the lens barrel or the lens hood It is characterized by being fixed removably.
[0008]
The lens cap of the present invention can be put on the tip portion of the lens barrel or the like by a simple operation of putting the lens cap so that the tip portion of the lens barrel or lens hood is inserted into the insertion groove. Further, the lens cap can be removed by a simple operation of pulling it out from the tip portion of the lens barrel. Moreover, if the depth and length of the insertion groove are set appropriately, it can be attached to a lens barrel having a flower-shaped tip without any inclination. Furthermore, by appropriately setting the length of the cylindrical body portion, the flower-shaped tip portion can be reliably sealed, so that it is possible to prevent dust and dirt from entering from outside and adhering to the lens surface.
[0009]
The insertion groove may be an annular insertion groove formed along an inner peripheral surface of the cylindrical body part and having a predetermined depth in the axial direction of the cylindrical body part.
[0010]
Further, if the groove width of the insertion groove is gradually reduced in the depth direction, it is possible to provide an appropriate attachment feeling and a stop feeling when the lens cap is attached. In particular, when the lens cap is an injection-molded product, the die structure can be simplified and the part accuracy can be improved by providing tapered surfaces on the both side surfaces of the insertion groove to the extent of the draft of the molding die. Since it becomes easy to take out, it is preferable.
[0011]
Furthermore, if a guide surface for guiding the tip of the lens barrel or lens hood is formed in the insertion groove on the inner peripheral surface of the cylindrical body, the lens cap can be easily attached. .
[0012]
Here, when the thickness of the tip of the lens barrel or the lens hood is thin, a sheet may be attached to at least one of the both side surfaces of the insertion groove. Further, a sheet may be affixed to adjust the dustproof property at the time of capping, the fixing force, and the operation feeling at the time of attachment.
[0013]
In the lens cap of the present invention, if an annular plate portion extending from the end plate portion along the inner peripheral surface of the cylindrical body portion in the axial direction of the cylindrical body portion is formed, the annular plate portion is formed. And the insertion groove is formed between the inner peripheral surface of the cylindrical body. The lens cap having such a structure can be obtained by resin injection molding.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a lens cap to which the present invention is applied will be described below with reference to the drawings.
[0015]
FIG. 1 is a plan view and a half sectional view showing a lens cap, and FIG. 2 is a half sectional view showing a state in which the lens cap is put on the flower-shaped tip of the lens barrel. As shown in these drawings, the lens cap 1 includes a cylindrical body 2, a disk-shaped end plate portion 3 that seals one end of the cylindrical body 2, and an insertion groove 4. The other end of the cylindrical body 2 is an open end 5. When the lens cap 1 is put on the lens barrel 6, the flower tip 7 is inserted into the insertion groove 4.
[0016]
The length in the direction of the axis 1a of the cylindrical body 2 of the lens cap 1 completely covers the tip surface portion 7a of the flower-shaped contour in the flower-shaped tip 7 of the lens barrel 6, as can be seen from FIG. The dimensions are set to be possible. Further, the inner peripheral surface 20 of the cylindrical body portion 2 has an inner peripheral surface portion 21 having the smallest diameter, an inner peripheral surface portion 22 having a slightly larger inner diameter that continues to the inner peripheral surface portion 21, and a slightly continuous portion. An inner peripheral surface portion 23 having a large inner diameter is provided, and the inner diameter spreads in three stages from the end plate portion 2 toward the opening end 5 little by little. Further, each of the inner peripheral surface portions 21, 22, and 23 is a tapered surface that slightly spreads outward toward the opening end 5.
[0017]
The end plate portion 3 has a shape in which the central portion is recessed toward the opening end 5, and an annular flat surface portion 31 that is continuous with the end of the cylindrical body 2, and the flat surface portion 31. Are formed of an annular inclined surface portion 32 continuous to the inner peripheral edge and a circular flat surface portion 33 continuous to the inner peripheral edge of the inclined surface portion 32. An annular plate portion 34 extends substantially in the direction of the axis 1 a from the back surface of the outermost annular flat surface portion 31, and the insertion groove 4 is formed by the annular plate portion 34.
[0018]
The length of the annular plate portion 34 is substantially the same as that of the inner peripheral surface portion 21 of the cylindrical body 2, and the outer peripheral surface 34 a of the annular plate portion 34 is slightly toward the opening end 5 side. The tapered surface is directed inward. Therefore, the groove width of the insertion groove 4 is a depth from the opening end 5 side by the inner peripheral surface portion 21 of the cylindrical body 2 and the outer peripheral surface 34a of the annular plate portion 34 which are both side surfaces with a taper. It gradually decreases in the direction.
[0019]
The lens cap 1 configured as described above can be put on the tip of the lens barrel 6 from the opening end 5 side. The lens cap 1 is positioned so that the flower-shaped tip 7 of the lens barrel 6 enters the open end 5 of the lens cap 1, and in this state, the lens cap 1 is pushed into the lens barrel 6 side. Since the inner peripheral surface 20 of the cylindrical body portion 2 of the lens cap 1 is defined by inner peripheral surface portions 23, 22, and 21 that gradually decrease in inner diameter from the opening end 5 side, the inner peripheral surface portion 23, A front end surface portion 7 a of the flower-shaped front end portion 7 of the lens barrel 6 is smoothly guided along the insertion groove 4 and inserted into the insertion groove 4.
[0020]
Since the both side surfaces 21a and 34a of the insertion groove 4 are tapered surfaces that widen toward the opening side, when the distal end surface portion 7a is inserted into the insertion groove 4, the insertion amount gradually increases. When the insertion resistance increases and the lens cap 1 is inserted to the state shown in FIG. 2, the user who is pushing the lens cap 1 receives a predetermined stop feeling and can perceive that the attachment of the lens cap 1 is completed. The lens cap 1 can also be removed by a simple operation of pulling the lens cap 1 from the lens barrel 6 in the direction of the axis 1a.
[0021]
In the state where the lens cap 1 is covered, as shown in FIG. 2, the tip surface 7 a of the flower-shaped tip 7 of the lens barrel 6 is completely covered by the cylindrical body 2 of the lens cap 1. . Therefore, the flower-shaped tip 7 of the lens barrel 6 is reliably protected by the lens cap 1, and dust or dust does not enter from the outside and adhere to the lens surface.
[0022]
Here, the lens cap 1 of this example can be a resin injection-molded product. In this case, it is desirable to attach tapered surfaces having the same angle in the same direction as the draft of the injection mold to both side surfaces 21 and 34a of the insertion groove 4. In this way, there is an advantage that the mold structure is simplified and the component accuracy is easily obtained.
[0023]
Next, when adjusting the operational feeling (insertion resistance, stop feeling) when attaching the lens cap 1, or when increasing the fixing force of the lens cap 1 to the lens barrel 6 with the thin tip surface 7a, The sheet may be attached to the inner peripheral surface 20 of the cylindrical body 2 in the case where the dustproof property in the capping state is enhanced or the impact resistance is improved.
[0024]
FIG. 3 is an explanatory diagram showing an example in which a sheet 8 having a low elastic property is attached to the inner peripheral surface portion 23 on the opening end 5 side of the cylindrical body portion 2 in order to improve impact resistance. By attaching the sheet 8 having an appropriate thickness, the outer peripheral surface portion of the opening end 5 of the cylindrical body 2 and the flower-shaped tip 7 of the lens barrel 6 in the state where the lens cap 1 is covered It will be in the state which stuck through. As a result, when an impact force is applied from the outside, the vibration of the opening end 5 of the cylindrical body 2 can be suppressed, and the impact resistance of this portion can be improved. In addition, since there is no gap, the dust resistance is improved.
[0025]
(Other embodiments)
In the lens cap 1 described above, annular insertion grooves are formed. However, for example, arc-shaped insertion grooves may be formed at a plurality of locations at regular angular intervals. It is also possible to form the insertion groove in the middle of the inner peripheral surface of the cylindrical body.
[0026]
Furthermore, it is also possible to use a material other than resin, for example, a metal as the material of the lens cap.
[0027]
【The invention's effect】
As described above, according to the lens cap of the present invention, the following effects can be obtained.
(1) Since it is formed from a single part, it is possible to realize an inexpensive lens cap capable of capping a flower tip such as a lens barrel.
(2) A lens cap that can be attached and detached by a simple operation and that is not attached obliquely to the flower-shaped tip can be realized.
(3) By appropriately setting the groove width of the insertion groove, it is possible to realize a lens cap that can be attached with a desired wearing feeling.
(4) Since it can be formed from resin or metal, it is possible to realize a highly durable lens cap with no change in the material over time.
(5) Since the tip opening and the outer peripheral surface of the flower-shaped tip part such as a lens barrel can be covered with a rigid member made of resin or the like, a lens cap with high protection performance can be realized.
(6) It is possible to realize a lens cap that does not generate dust and dust and can reliably prevent dust and dust from entering from the outside.
(7) A lens cap having a good appearance when capping can be realized.
[Brief description of the drawings]
FIG. 1 is a plan view and a half sectional view of a lens cap to which the present invention is applied.
FIG. 2 is an explanatory view showing a state in which the lens cap of FIG. 1 is put on the tip of a lens barrel.
3 is a half cross-sectional view showing an example in which a sheet is affixed to an inner peripheral surface of a cylindrical body portion of the lens cap of FIG. 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Lens cap 1a Axis 2 Cylindrical trunk | drum 20 Inner peripheral surface 21, 22, 23 Inner peripheral surface part 3 End plate part 34 Annular plate part 34a Outer peripheral surface 4 Insertion groove 5 Open end 6 Lens barrel 7 Flower-shaped tip Part 7a Tip surface 8 Sheet

Claims (7)

A tubular body,
An end plate portion sealing one end of the cylindrical body,
An insertion groove formed inside the cylindrical body,
Due to the engagement force between the insertion groove and the lens barrel or the front end portion of the lens hood inserted into the insertion groove from the opening end of the cylindrical body portion, the front end portion of the lens barrel or the lens hood Lens cap fixed removably. In claim 1,
The said insertion groove is a lens cap which is formed along the internal peripheral surface of the said cylindrical trunk | drum, and is an annular insertion groove of predetermined depth in the axial direction of the said cylindrical trunk | drum. In claim 1 or 2,
A lens cap in which the groove width of the insertion groove gradually decreases in the depth direction. In claim 1, 2 or 3,
The lens cap in which the guide surface for guiding the front-end | tip part of a lens-barrel or a lens hood is formed in the said insertion groove | channel on the inner peripheral surface of the said cylindrical trunk | drum. In any one of claims 1 to 4,
A lens cap in which a sheet is attached to at least one side surface of both side surfaces of the insertion groove. In any one of claims 1 to 5,
An annular plate portion extending in the axial direction of the cylindrical body portion from the end plate portion along the inner peripheral surface of the cylindrical body portion;
A lens cap in which the insertion groove is formed between the annular plate portion and the inner peripheral surface of the cylindrical body portion. In claim 6,
Lens cap made of resin molding.

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