JPH0711662B2 - Eye hood - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an eye hood, and more particularly to an eye hood in which a hood portion is made of a thermoplastic elastic body and a base portion is made of a hard resin, and both are heat-sealed. More specifically, the present invention relates to an eye hood whose base has a means for attaching to a camera body.

[Prior Art] Conventionally, in cameras, microscopes, binoculars, and the like, an eye hood is attached to a portion in contact with the face, that is, an eyepiece lens portion. This eye hood is designed so that the face of the camera can be softly hit by the face, and can be used as a shade to prevent unnecessary light from entering the visual field. Furthermore, it is said that it is to reduce the feeling of cold discomfort directly from the camera. For this reason, the eye hood is made of a flexible resin (thermoplastic elastic body, etc.) which is flexible and has a high rubber elasticity.

If you attach this eye hood directly to the camera body, etc., the soft resin is too soft, so you cannot use fixing means such as screwing, fitting, bayonet coupling, etc. Even if you use these mechanisms, you can use it. Was not enough to withstand. The reason is as follows. If you bring your eyes close to the camera to bring them into close contact, the eye hood will receive a compressive force if you bring them close to each other exactly.
If they are approached diagonally, they will receive bending force. This time, if the camera is shaken slightly left and right while in contact, the eye card will be twisted and sheared.

In some cases, it also acts to narrow down. That is,
As described above, since the connecting portion of the soft resin with the camera body is subjected to various stresses, it is necessary to have a connecting force to withstand the stress. But that was not always enough. Therefore, the eye hood itself is once held and fixed with a hard resin or a metal member, and then attached to the camera body. That is, the hard resin or the metal member is attached by providing a fitting means with the camera body. Also, a method has been used in which the eye hood itself is entirely pressed down onto the camera body or the like to be attached.

However, because of the various stresses mentioned above,
The part that was gripped and the part that was pressed down were heavily used, and there were not many gaps, resulting in looseness, slippage, and lack of durability. In particular, in the case of pressing and mounting, since the pressing member must be provided on the camera body side, the mounting means inevitably becomes complicated and the number of steps for assembling increases.

[Problems to be Solved by the Invention] The present invention has been made as a result of extensive research to solve the above problems. That is, the eye hood is made up of a soft resin portion rich in rubber elasticity (mainly a thermoplastic elastic body).
And a dimensionally stable base composed of a rigid portion (hard resin), and the base is attached to the body of a camera or the like.

Since the mounting means for connecting to the camera body is provided at the base of the eye hood itself, it is possible to simply mount the eye hood without the need for a gripping member or a pressing down. The base portion of the hard resin is not soft and dimensionally stable unlike the soft resin which is rich in rubber elasticity, so that it can be coupled to the camera body without any error.

On the other hand, when the soft resin and the hard resin are conventionally heat-sealed, there is a problem in the adhesive strength. In other words, the adhesive strength is low,
In particular, the adhesiveness between the thermoplastic resin (thermoplastic elastomer) made of synthetic resin excellent in rubber elasticity and the hard resin is extremely poor, and sufficient bonding strength cannot be guaranteed.

In the present invention, when the soft resin and the hard resin are adhered to each other, particularly when the thermoplastic elastic body excellent in rubber elasticity and the hard resin are heat-sealed, the substance (polyether block amide or It has been found that the polyester-based thermoplastic elastomer) is bonded very strongly to each other by blending it, and as a result, it is suitable for bonding a thermoplastic elastic body and a hard resin by using it in a camera hood. Then, by directly mounting the base portion of the hard resin to the camera, it was possible to surely connect it to the camera body.

[Means for Solving the Problems] The configuration of the present invention will be described below.

The most significant feature of the present invention is that the hard resin and the thermoplastic elastic body rich in elasticity have a polyether block amide in the latter in order to strongly improve the adhesive force between the two, and also the same. That is, the polyester-based thermoplastic elastomer was contained.

As a result, an eye hood could be made by integrating a hard resin, which is the material of the base portion that directly comes into contact with the camera, with a thermoplastic elastic body having a high elasticity, which is the material of the hood portion.
As a result, the base of the eye hood can be directly attached to the camera body, and reliable connection with the camera body is possible. The polyether block amide or polyester thermoplastic elastomer is represented by the following formulas (1) and (2).

However, PA: shows a block of polyamide which is a hard segment.

PE: shows a block of polyether which is a soft segment.

The polyether block amide represented by the general formula (1) is, for example, a) a salt of a diamine and a dicarboxylic acid, a lactam, or an aminocarboxylic sun (PA constituent component) b) a polyoxyethylene glycol, a polyoxypropylene glycol or the like polycarboxylic acid. Oxyarnelylene glycol (PE constituent) c) Dicarboxylic acid prepared by polycondensation and is known.

It is still unknown why the polyether block amide represented by the general formula (1) strongly adheres to the hard resin, but the functional groups such as hard segment, soft segment, OH and COOH of the polyether block amide are effective. It can be inferred that there will be a result of the effects on each other.

The polyester-based thermoplastic elastomer represented by the general formula (2) is prepared by subjecting dimethyl terephthalate, 1.4-butanediol and poly (oxytetramethylene) glycol as starting materials to a polycondensation reaction and a transesterification reaction.

The polyester-based thermoplastic elastomer has a hard segment and a soft segment. Polyester thermoplastic elastomers of this type include polyester segments (hard segments) prepared from aromatic dicarboxylic acids and short-chain glycols, and poly-segments prepared from aromatic dicarboxylic acids and polyalkylene glycols (long-chain glycols). There are polyether-ester type copolymers having an ether segment (soft segment). Polyester / ester type copolymers prepared by using polycaprolactone as the soft segment are also known.

On the other hand, it is not yet known why the polyester thermoplastic elastomer represented by the general formula (2) strongly adheres to the hard resin, but like the polyether block amide, the hard segment and soft segment of the polyester thermoplastic elastomer. It can be inferred that there may be a result that functional groups such as OH, COOH, etc. act effectively.

Next, the thermoplastic elastic body combined with the polyether block amide or polyester thermoplastic elastomer will be described. The thermoplastic elastic body used for the hood portion in the present invention may be any flexible resin having rubber elasticity and flexibility.

For example, hydrogenated SBS block polymer, olefin elastomer such as FPR, diene elastomer such as SBR,
Examples include urethane-based elastomers and plasticized polyvinyl chloride that is highly elastic and contains a plasticizer. In particular, in order to obtain an eye food with high added value, it is desirable to use a thermoplastic elastic body having a hardness (JIS Shore hardness A) of 70 to 35 degrees.

In order to prepare a thermoplastic elastic composition having excellent heat fusion properties from the above-mentioned polyether block amide or polyester thermoplastic elastomer and the thermoplastic elastic component,
From the viewpoint of ensuring sufficient fusion bonding strength, 100 parts by weight of the thermoplastic elastic material component, the polyether block amide or polyester thermoplastic elastomer is 25 ~
Used 185 parts by weight. Particularly preferably, a mixture in which 40 to 60 parts by weight of a polyether block amide or polyester thermoplastic elastomer is mechanically blended with 100 parts by weight of a thermoplastic elastic material and uniformly dispersed in a sea-island shape is used.

The hard resin used for the eye hood base of the present invention is a thermoplastic engineering plastic such as polycarbonate, nylon 11, nylon 12, ABS resin, methacrylic resin or a thermoplastic synthetic resin. Among these synthetic resins, one having a hardness of 70 or more may be used in order to obtain a high value-added eye hood.

[Example 1] Hereinafter, an example will be described.

FIG. 1 is a diagram showing an outline of the video camera 1, FIG. 2 is an outline diagram showing an eye hood attaching means, and FIG.
The figure is a sectional view thereof. The eyepiece part 3 is made of a thermoplastic elastic material and is shaped so that when the eye hood 2 is applied to the face, it is in close contact with the face and unnecessary light does not enter. The base 4 is made of a hard resin such as engineering plastic. A claw piece 5 is provided on the outer periphery of the base 4 of the hard resin. One of the claw pieces 5 is attached by being caulked by a protrusion 6 extending from the base portion 4, and the other end has a tip thereof bent outward to form a claw 7.

The claw piece 7 is caulked and attached to the base portion 4, but since it is elastically expanded outward from the caulking portion, the pawl piece 7 is screwed while rotating along the threaded portion 11 engraved in the body 10 of a camera or the like. The attachment strength between the main body 10 such as a camera and the eye hood can be freely selected depending on the strength of the elastic force of the claw piece 5. Here, the nail piece 5 is provided on the side of the eye hood 2 and the threaded portion 11 is provided on the body 10 of the camera or the like, but the threaded portion 11 may be provided on the side of the eye hood on the body 10 of the camera or the like. good.

Further, although the camera side has internal threads, it is of course possible to use external threads. The adhesive portion between the eyepiece portion 3 of the thermoplastic elastic body and the base portion 4 of the hard resin is heat-sealed, but when the protrusion portion is provided on one side and the concave portion 8 is provided on the other side and they are fitted to each other and heat-sealed, an adhesive area is obtained. Is larger, and stronger adhesion can be achieved.

[Second Embodiment] FIG. 4 shows another mounting means. A rail portion 17 is provided on the inner peripheral surface of the base portion 4 made of a hard resin, and a notch portion 15 for inserting a protrusion 16 on the camera body side is provided. Further, the camera body has a protrusion 16. To fit the eye hood 2 into the camera, the notch 15 of the base 4 is brought into contact with a portion corresponding to the protrusion 16 of the camera body, and the base 4 of the hood 2 is inserted.
After pushing in, the protrusion 16 is slid along the rail 17 by rotating it as it is.

Normally, the middle groove of the rail portion 17 has a taper interval, so that it is tightened as the base portion 4 rotates. Since such a bayonet connection can be exchanged with each other, it is the same even if the notch 15 is provided in the camera body and the projection 16 is provided in the base 4 of the other eye hood 2.

Although the eye hood such as a camera has been described above, the present invention is not limited thereto, and a lens hood,
It can also be applied to lens caps. As a reference example, an experimental result in which the hood portion of the thermoplastic elastic composition and the base portion of the hard resin are heat-sealed will be shown below.

Reference Example 1 Next, a reference example in the case where the eye hood is molded by heat-sealing the hood portion made of a thermoplastic elastic body and the base portion made of a hard resin will be shown below.

A thermoplastic elastic composition was prepared as follows. As the thermoplastic elastic body, S, E, B, S (hydrogenated SBS block copolymer, registered trademark "Lavalon" T3427C, manufactured by Mitsubishi Yuka Co., Ltd.) Of 100 parts, and polyether block amide (registered trademark "Pebax" 6333SA00, SP value 10.2-1
55 parts of 0.8, manufactured by Toray Industries, Inc.) were uniformly blended to obtain a blend product in which both components were branched in a sea-island shape.

An experiment was carried out in which the thermoplastic elastic composition prepared as described above was heat-sealed to a polycarbonate molded article to form a composite molded article.

That is, the main body of the underwater glasses is injection-molded in advance with a polycarbonate, and then the main body of the underwater glasses of this polycarbonate is heat-sealed and bonded by the injection molding means to the above-mentioned thermoplastic elastic composition, and the face contact portion is formed. Formed.
(The overall structure of the underwater glasses is described in Japanese Patent Publication No. 62-23577.) The injection molding conditions are: nozzle temperature 220 ° C, cylinder temperature 180 ° C, die bottom temperature 140 ° C, mold temperature 50 ° C. , The injection pressure is 400kg / cm ² .

The joint surface between the polycarbonate and the thermoplastic elastic composition was strongly adhesively fused. The adhesive strength was the same as the tensile strength of the thermoplastic elastic body. That is, the poly carbonate and the S, E, B and S were completely fused.

Under the same conditions as above, 100 parts of the thermoplastic elastic material and 25 parts and 185 parts of the polyether block amide were also completely fused.

[Reference Example 2] In the example, heat was applied by using TPO (olefin-based thermoplastic elastomer), (trade name "Miralastomer" 5030N, manufactured by Mitsui Petrochemical Co., Ltd.) in place of S, E, B and S. When fusion-bonded, the joint surface was completely fusion-bonded.

[Reference Example 3] In Example 1, S-E-B-S was replaced with styrene-
Butadiene-styrene (SBS, trade name "Elastomer A
R ”AR140, manufactured by Aron Kasei Co., Ltd.) was used to prepare a thermoplastic elastic composition and fusion-bonded it, the bonding surface was completely fusion-bonded.

[Reference Example 4] A thermoplastic elastomer composition was prepared using a thermoplastic elastomer (trade name "Aron AR" 740BK, manufactured by Aron Kasei Co., Ltd.) in place of S, E, B, S in Reference Example 1. When fusion bonding was performed, complete fusion bonding was performed on the bonding surface.

[Reference Example 5] In Example 1, instead of polycarbonate, ABS resin (acrylonitrile-butadiene-styrene-based resin), (trade name "Denka ABS" GR-1000, manufactured by Denki Kagaku Kogyo Co., Ltd.) was used for fusion bonding. When joined, the joint surface was fusion bonded with sufficient strength.

[Reference Example 6] In Example 1, when fusion bonding was performed using a methacrylic resin (trade name "Acrylic PET", manufactured by Mitsubishi Rayon Co., Ltd.) instead of polycarbonate, the bonding surface was melted with sufficient strength. I joined them.

[Reference Example 7] Instead of the polycarbonate of Example 1, a preformed 11-nylon machine part is placed in a mold. The other conditions were the same as in Example 1, and a polymer blend of the same thermoplastic elastomer and polyether block amide was injection molded and fusion bonded. The joint surface was completely fused.

[Reference Example 8] In Example 7, when 12 nylon was used instead of 11 nylon for fusion bonding, the joint surface was completely fusion bonded.

In addition to the above, in the above-mentioned Reference Examples 1 to 8, polyether block amide (registered trademark "Pebax" 6333SA00, SP
Value 10.2-10.8 manufactured by Toray Industries Co., Ltd., polyester-based thermoplastic elastomer (registered trademark "Grelax" E
-120, manufactured by Dainippon Ink and Chemicals, Inc. was also used, and in any case, the fusion bonding was performed at a sufficient temperature.

Although the eye hood of a camera or the like has been described above, the present invention is not limited to this, and can be applied to a lens hood, a lens cap, and the like.

EFFECTS OF THE INVENTION The present invention comprises an eye hood including a hood portion made of a soft portion (thermoplastic elastic body) rich in rubber elasticity and a dimensionally stable base portion made of a hard portion (hard resin). Since this base has a structure to be directly attached to the body of a camera or the like, and the base of the eye hood itself is provided with an attachment means for connecting to the body of the camera or the like, it is easy to eliminate the need for a gripping member or a pressing member as in the past. Easy to install. In addition, the gripped portion or the pressed portion is not overused and the gap is widened, resulting in no looseness or displacement. Moreover, unlike the hard resin which is rich in rubber elasticity, the base portion of the hard resin is not soft and is dimensionally stable, so that it can be connected to the camera body without any error.

On the other hand, the heat fusion between the hood portion of the thermoplastic elastomer composition and the base portion of the hard resin is extremely strongly bonded by the blend of the polyether block amide or polyester thermoplastic elastomer and the thermoplastic elastomer. Therefore, sufficient durability is guaranteed even if the eye hood is subjected to the various stresses described above.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a video camera, FIG. 2 is a diagram showing an outline of an eye hood, FIG. 3 is a partial sectional view of FIG. 2, and FIG. 4 is an eye hood of a second embodiment. It is a figure. 1 ... video camera, 2 ... eye hood, 3 ... eyepiece, 4 ... base, 5 ... nail piece, 6 ... protrusion

Claims (7)

[Claims] 1. An eye hood in which a hood portion is made of a thermoplastic elastic material composition and a base portion is made of a hard resin, and both are heat-sealed and joined. 2. The eye hood according to claim 1, wherein the hood portion of the thermoplastic elastic composition and the joint surface of the base portion of the hard resin are fitted to each other. 3. The eye hood according to claim 1 or 2, wherein the base has a means for attaching to the camera body. 4. The eye hood according to claim 1, wherein the thermoplastic elastomer composition contains a polyether block amide. 5. In one claim selected from claims 1 and 2,
An eye hood comprising a thermoplastic elastomer composition a) 100 parts by weight of thermoplastic elastomer b) 25 to 185 parts by weight of polyether block amide. 6. An eye hood according to claim 1, wherein the thermoplastic elastic composition contains a polyester thermoplastic elastomer. 7. The thermoplastic elastic composition according to claim 1, wherein the thermoplastic elastic composition is a) 100 parts by weight of a thermoplastic elastic material and b) 25 to 185 parts by weight of a thermoplastic polyester elastomer. Eye food.