Cane and Cylindrical Body

Abstract

Provided is a cane that has a sufficient impact-resistant strength; and is excellent in safety, durability and repairability and also lightweight but has a high stiffness. Such a cane has a shaft (4) and a grip,the shaft (4) comprising a high-strength-organic-fiber-reinforced-resin layer (31) and a carbon-fiber-reinforced-resin layer (32),the high-strength-organic-fiber-reinforced-resin layer (31) being integrally laminated onto each of the outside and inside surfaces of the carbon-fiber-reinforced-resin layer (32),the shaft (4) comprising a glass-fiber-reinforced-resin layer (33a) on the inner side of the innermost high-strength-organic-fiber-reinforced-resin layer (31a),the shaft (4) comprising a glass-fiber-reinforced-resin layer (33b) on the outer side of the outermost high-strength-organic-fiber-reinforced-resin layer (31b).

Description

TECHNICAL FIELD[0001]The present invention relates to a cane such as a white cane for the visually disabled. More particularly, the present invention relates to a cane that has a sufficient impact-resistant strength against a force in a direction perpendicular to the axis of its shaft; and is excellent in safety, durability and repairability and also lightweight but has a high stiffness.BACKGROUND ART[0002]A cane is also called a stick or a pole, and used not only by the visually disabled and people with limb disabilities, such as elderly people, but also by healthy people for trekking, light mountain climbing, etc. Such a cane usually has a rod-shaped shaft, a grip which is designed for the user to grasp and formed at the upper end of the shaft, and a ferrule attached to the lower end of the shaft. Conventional canes, although are more or less structurally different from each other, are made of wood, an aluminum alloy, etc. in the most cases.[0003]For example, a so-called white can...

AI Technical Summary

Benefits of technology

[0040]The present invention, which has constitutions and functions as described above, exhibits the following effects.(1) Since the carbon-fiber-reinforced-resin layer has a high stiffness, even when given a force in the axial direction, the shaft does not curve or bend, and thus the user can use the cane with a sense of security.(2) Since the high-strength-organic-fiber-reinforced-resin layer is excellent in vibration damping, vibration etc. of the tip of the cane can be accurately transmitted to the user's hand.(3) Since a lightweight high-strength-organic-fiber-reinforced-resin layer and a highly stiff carbon-fiber-reinforced-resin layer are comprised in combination, the shaft and the cylindrical body each have a high strength and are lightweight without the need of an excessively thick high-strength-organic-fiber-reinforced-resin layer.(4) Since the high-strength-organic-fiber-reinforced-resin layer is comprised, even when the user hits the ground, obstacles, etc. with the tip of the cane, there is no possibility of impact-triggered microcrack generation in the high-strength organic fiber, and thus the durability is excellent.(5) Even when a great flexural impact is applied in a direction perpendicular to the axial direction, the high-strength-organic-fiber-reinforced-resin layer can buffer the impact by buckling deformation, deliver an excellent performance in mechanical strength such as impact resistance, and thus favorably prevent the shaft from fracturing.(6) Even if carbon fibers break in response to a great flexural impact in a direction perpendicular to the axial direction, the carbon-fiber-reinforced-resin layer is protected by the high-strength-organic-fiber-reinforced-resin layer integrally laminated onto the outside surface thereof, and thus heavily fracturing is prevented. Broken spiky carbon fibers are also prevented from projecting from the site to which the flexural impact has been given. Accordingly, for example, the visually disabled etc. can safely check such a damaged site by touch or the like.(7) Since each of the shaft and the cylindrical body does not easily fracture even when given a great flexural impact in a direction perpendicular to the axial direction, they can be easily repaired by use of, for example, a commercial repair kit etc., for example, at the venue where the impact has been given, and the repaired cane etc. can be continuously used.

Problems solved by technology

For example, a so-called white cane for the visually disabled is usually used with its tip slightly lifted from the ground for a prolonged period, and thus weight saving is desired, but conventional wooden canes are heavy and give a heavy burden to the users.

Furthermore, such wooden canes are unsatisfactory in strength, and may be repeatedly swelled and dried by environmental changes, resulting in undesired warpage of the shaft and detachment of the superficial coating thereof.

Aluminum alloy canes are more lightweight than wooden canes, but still heavy for prolonged use and disadvantageously tend to dent and bend in response to impact.

However, the cane according to Patent Literature 1, although is more lightweight than conventional canes made of wood, an aluminum alloy, etc., is not lightweight enough, particularly to allow the visually disabled etc. to use for a prolonged period, and thus further weight saving is desired.

However, since carbon fibers as inorganic fibers have a low elongation and lack flexibility, the shaft disadvantageously tends to break in response to an impact in a direction transverse to the shaft (flexural impact).

Considering this, the above-mentioned shaft has a sufficient mechanical strength as a golf shaft in striking, but is unsatisfactory as a cane shaft.

This is because a cane using this shaft is given an impact when the user frequently hits the road surface and obstacles with the cane in order to examine their conditions, and the impact is transmitted to the shaft via the ferrule and may cause microcracks in the carbon fiber.

Thus, when given an external force by bumps (against a person, a bicycle and other obstacles), etc., the cane may easily fracture at the site where cracks have been generated.

Further, the above-mentioned cane having a shaft made of a carbon fiber-reinforced resin may fracture in response to impact etc., be heavily damaged on the fracture surface, and have spiky ends of stiff fibers projected from the fracture surface.

In this case, for example, when the visually disabled check the fracture site and the damage level, naturally by touch, the fibers exposed on the fracture surface may get stuck in the hand.

Further, the repairability of the above-mentioned cane is unsatisfactory because the fracture site is damaged so heavily that simple repair on site is difficult.

However, such a shaft is excellent in impact resistance but has a lower stiffness compared with the shaft formed of a carbon fiber-reinforced resin.

This stiffness of the shaft can be enhanced by thickening the layer of the high-strength organic fiber-reinforced resin, but in this case, the shaft is thicker, the amount of the resin used is increased and the weight of the cane is excessively increased.

Images