JP2006230571A - Float made of synthetic resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a float with a buoyant cylindrical part used for making a course rope float for a swimming pool or the like which is excellent either in the prevention of scratching and the buoyancy. <P>SOLUTION: The cylindrical part 12 of the float 2 is formed in a multi-layer structure with a plurality of synthetic resin foam layers 4, 6, 8 and 10 laminated. The innermost synthetic resin foam layer 4 is formed out of a high-density synthetic resin foam material sufficiently withstanding scratching, the intermediate synthetic resin foam layers 6 and 8 are formed out of a low-density synthetic resin foam material able to hold a sufficient buoyancy and the outermost synthetic resin foam layer 10 is formed out of a low density synthetic resin foam material with a better skin touch. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a synthetic resin float used for floating a course rope used in a pool, a rope that divides a swimming prohibited area, and the like on a water surface.

  Conventionally, as a course rope 70 used in a pool as shown in FIG. 6 or a rope stretched on the water surface to divide a swimming prohibited area, a stainless steel wire mainly provided with a corrosion protection coating is used. Although used, the floater 72 is generally attached to the rope as a levitation body in order to submerge itself without buoyancy (see, for example, Patent Document 1). A material of the floater is mainly a non-foamed polyolefin resin. As a structure, a hollow thermoformed processed body or an injection molded processed body in which a groove for wave elimination is formed on the outer surface is known.

  Japanese Patent Laid-Open No. 10-192565 proposes a course rope floater formed by molding a resin foam. This floater is manufactured by adding a foaming agent to a synthetic resin and performing molding and foaming in a mold, and the entire floater is an integrally molded product having the same density.

Japanese Utility Model Publication No. 5-200

  However, among the above-described conventional floaters, the hollow thermoformed processed body made of non-foamed polyolefin resin has a thin resin layer and is easily damaged by an external force. In addition, the damaged cut end has the disadvantage of causing a laceration to the human body if it is sharply damaged, and scratching the human body if it is damaged in a jagged manner. Similarly, an injection-molded processed body made of non-foamed polyolefin resin has a risk that the damaged opening may damage the human body.

  On the other hand, the resin foam floater disclosed in Japanese Patent Application Laid-Open No. 10-192565 is less likely to break, and even if breakage (chip) occurs, there is little risk of the breakage opening damaging the human body. However, since this resin foam floater is integrally molded, it is formed with the same density as a whole. Therefore, if it is made of a low density resin foam with emphasis on buoyancy and touch to the human body, it is easy to be damaged. When it was formed with a high-density resin foam with emphasis on prevention, the touch was poor, and it gave a hard and painful feel when touched by the human body.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a synthetic resin levitated body that is favorable in terms of both prevention of trauma and buoyancy.

  In order to achieve the above object, the present invention is a levitation body including a cylindrical portion having buoyancy, wherein the cylindrical portion has a multilayer structure in which a plurality of synthetic resin foam layers are laminated, and The innermost synthetic resin foam layer among the plurality of synthetic resin foam layers is a high-density synthetic resin foam layer that can withstand trauma, and at least one of the outer synthetic resin foam layers is sufficient. Provided is a synthetic resin levitation body characterized by being a low-density synthetic resin foam layer capable of maintaining high buoyancy.

  The synthetic resin levitation body of the present invention has a cylindrical portion formed in a multilayer structure in which a plurality of synthetic resin foam layers are laminated, and the innermost synthetic resin foam layer has a high density synthetic resin foam that can withstand external damage. Since the body layer is used, it is possible to effectively prevent the tubular portion from being damaged by a rope or the like inserted into the tubular portion. Further, since at least one of the outer synthetic resin foam layers of the innermost synthetic resin foam layer is a low density synthetic resin foam layer capable of maintaining sufficient buoyancy, the buoyancy is sufficient. Furthermore, if the outermost synthetic resin foam layer is a low-density synthetic resin foam layer that is soft to the touch, a soft touch can be imparted when touching the human body.

  It is preferable that the synthetic resin levitation body of the present invention is subjected to corrugation molding processing (processing to impart a shape such as a groove, unevenness, and corrugation that can be wave-dissipated on the outer surface) on the outer surface. As a result, the waves can be quenched, and the course rope used in the pool, the rope for dividing the swimming prohibited area, and the like can be suitably used as a floater that floats on the water surface. Examples of the corrugated molding process include, but are not limited to, a process of providing a wave-destructible groove, unevenness, corrugation, and the like on the outer surface of the synthetic resin floating body by heat molding.

  In the present invention, each of the plurality of synthetic resin foam layers is preferably composed of a synthetic resin foam having a closed cell structure. Specifically, closed cells such as crosslinked polyethylene foam, uncrosslinked polyethylene foam, crosslinked polypropylene foam, uncrosslinked polypropylene foam, crosslinked vinyl acetate foam, uncrosslinked vinyl acetate foam, or composite structures thereof. A foam having a structure is preferable.

In the present invention, the apparent density of the high-density synthetic resin foam layer capable of withstanding the damage is 50 to 200 kg / m ³ , particularly 100 to 200 kg / m ³ in terms of obtaining a good damage prevention effect. Is appropriate.

In the present invention, the apparent density of the low-density synthetic resin foam layer capable of maintaining sufficient buoyancy is 18 to 50 kg / m ³ , particularly 35 to 50 kg / m ³ in terms of obtaining sufficient buoyancy. Is appropriate.

In the present invention, when the outermost synthetic resin foam layer is a low-density synthetic resin foam layer that is soft to the touch, the apparent density of the low-density synthetic resin foam layer is to obtain a good touch. It is suitable that it is 18-50 kg / m ³ , especially 18-35 kg / m ³ .

Moreover, as a suitable aspect of the synthetic resin floating body of this invention, as shown in embodiment mentioned later, the following aspect is mentioned, for example.
(1) The cylindrical portion is formed in a cylindrical shape by winding a long sheet made of a synthetic resin foam into a spiral shape, and a long piece made of one or more synthetic resin foams around the cylindrical sheet. The aspect which has the structure which gave the corrugation shaping | molding process to the outer surface of the cylindrical body formed by winding a sheet | seat in a spiral shape (refer FIG. 2, 3).
(2) The cylindrical part is a rectangular sheet made of a synthetic resin foam and is wound into a cylindrical shape with its side edges abutting on each other, and a rectangular sheet made of one or more synthetic resin foams around the cylindrical sheet. An embodiment having a structure in which a corrugated forming process is applied to the outer surface of a cylindrical body formed by winding the sheet into a cylindrical shape with the side edges thereof in contact with each other (see FIG. 5).

  In addition, in the synthetic resin floating body of this invention, there is no limitation in particular in the thickness and the number of layers of a synthetic resin foam layer, According to the intended purpose etc., it can set suitably. The synthetic resin levitation body of the present invention suitably has an inner diameter of 8 to 20 mm, an outer diameter of 30 to 100 mm, and a length of 300 mm or less. In this case, by appropriately setting the inner diameter, outer diameter, and length of the synthetic resin levitation body, when winding the inserted rope or the like, the rope or the like can be wound with a small diameter or with a large diameter. It becomes possible.

  As described above, the synthetic resin levitation body of the present invention is good in both points of preventing trauma and buoyancy.

  Next, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited to the following examples. FIG. 1 is a perspective view showing an example of a synthetic resin floating body according to the present invention. This synthetic resin floating body 2 is a floater that floats a course rope used in a pool, a rope that divides a swimming prohibited area, etc. on the water surface. Used as.

  The synthetic resin levitation body 2 in FIG. 1 includes a cylindrical portion 12 having a multilayer structure (four-layer structure) in which a plurality of synthetic resin foam layers 4, 6, 8, and 10 are stacked. In this case, in the cylindrical portion 12, the innermost synthetic resin foam layer 4 is made of a high-density synthetic resin foam that can withstand trauma, and the two intermediate synthetic resin foam layers 6 and 8 have sufficient buoyancy. The outermost synthetic resin foam layer 10 is made of a low density synthetic resin foam that is comfortable to the touch. Further, the outer surface of the synthetic resin levitation body 2 of this example is subjected to corrugated molding.

  FIG. 2 is a cross-sectional view showing another example of the synthetic resin floating body according to the present invention, and this synthetic resin floating body 22 is also used for the same application as the synthetic resin floating body of FIG. The synthetic resin floating body 22 in FIG. 2 includes a cylindrical portion 32 having a multilayer structure (four-layer structure) in which a plurality of synthetic resin foam layers 24, 26, 28, and 30 are laminated. In this case, in the cylindrical portion 32, the innermost synthetic resin foam layer 24 is made of a high-density synthetic resin foam that can withstand trauma, and the two intermediate synthetic resin foam layers 26 and 28 have sufficient buoyancy. The outermost synthetic resin foam layer 30 is made of a low density synthetic resin foam that is comfortable to the touch. Further, in the synthetic resin floating body 22 of this example, a protective pipe 34 made of synthetic resin is inserted inside the innermost synthetic resin foam layer 24, and the outer surface of the outermost synthetic resin foam layer 30 is made of synthetic resin. The protective film 36 is covered. The synthetic resin levitation body of the present invention includes those in which another layer is added to the inside or the outside of a cylindrical portion formed of a plurality of synthetic resin foam layers as in this example. Further, the outer surface of the synthetic resin floating body 22 of this example is subjected to corrugated molding.

  The synthetic resin floating body 22 of FIG. 2 can be manufactured as follows, for example. First, as shown in FIG. 3, a long first sheet 24 made of a synthetic resin foam (corresponding to the synthetic resin foam layer 24 in FIG. 2) is spirally formed around a core 40 made of synthetic resin or the like. A long second sheet 26 made of a synthetic resin foam (corresponding to the synthetic resin foam layer 26 in FIG. 2) is spirally wound around the first sheet 24 formed into a cylindrical shape by winding. Then, a long third sheet 28 (corresponding to the synthetic resin foam layer 28 in FIG. 2) is spirally wound around the second sheet 26, and then around the third sheet 28. A long fourth sheet 30 made of a synthetic resin foam (corresponding to the synthetic resin foam layer 30 in FIG. 2) is spirally wound, and then a long synthetic resin film 36 ( Spy on the protective film 36 in FIG. To create a cylindrical body 42 by winding in Le shape. Next, for example, by using a molding machine having an upper mold 44 and a lower mold 46 as shown in FIG. 4, the outer surface of the cylindrical body 42 is subjected to corrugated molding processing such as grooves, irregularities, and corrugations by heat molding. A synthetic resin protective pipe 34 is inserted into the inner synthetic resin foam layer 24 to obtain the synthetic resin floating body 22. The cylindrical body 42 may be cut in advance in accordance with the length of the synthetic resin floating body 22 to be manufactured and then subjected to corrugated molding processing. You may perform a wave forming process in the state which has length (for example, about 4000 mm).

  The cylindrical body can be manufactured by other methods. For example, as shown in FIG. 5, a rectangular inner layer sheet 50 made of a synthetic resin foam is wound into a cylindrical shape with the side edges 52 in contact with each other, and then the synthetic resin is wrapped around the inner layer sheet 50 wound into a cylindrical shape. A rectangular intermediate sheet 54 made of foam is wound into a cylindrical shape with the side edge portions 56 in contact with each other, and a rectangular outer layer sheet 58 made of a synthetic resin foam is wound around the intermediate sheet 54 wound in a cylindrical shape. The cylindrical body 62 may be manufactured by bringing the side edge portion 60 into contact with each other and winding it into a cylindrical shape. Note that another layer (for example, a protective layer) made of a synthetic resin or the like may be provided on the inner side of the inner layer sheet 50 or on the outer side of the outer layer sheet 58.

Example 1
A synthetic resin floating body 2 having a four-layer structure as shown in FIG. 1 was produced. In this case, first, a cylindrical body 42 was formed by the method shown in FIG. 3 using a long sheet made of a synthetic resin foam. Specifically, a cross-linked polyethylene foam having a thickness of 2.5 mm and an apparent density of 100 kg / m ³ as a sheet of the innermost layer 4 is processed to a width of 25 mm, and a sheet of the intermediate layers 6 and 8 has a thickness of 7 mm and an apparent thickness, respectively. A cross-linked polyethylene foam having a density of 45 kg / m ³ processed to a width of 25 mm, and a sheet of the outermost layer 10 having a thickness of 2.5 mm and a cross-linked polyethylene foam having an apparent density of 18 kg / m ³ processed to a width of 25 mm are used. These sheets are heat-sealed while being spirally wound around a core member 40 having an outer diameter of 11 mm (adhesion may be used, the same applies hereinafter), and further cut to form a cylinder having an inner diameter of 12 mm, an outer diameter of 50 mm, and a length of 250 mm A body 42 was obtained. Next, in a state where the shaft center having an outer diameter of 11 mm is passed through the cylindrical body 42, a molding machine having an upper mold 44 and a lower mold 46 as shown in FIG. A synthetic resin floating body 2 having a length of 250 mm was produced by corrugated molding.
(Example 2)
In the same manner as in Example 1, a synthetic resin floating body 2 having a four-layer structure was produced. In this case, a cross-linked polyethylene foam having a thickness of 2.5 mm and an apparent density of 100 kg / m ³ as a sheet of the innermost layer 4 is processed to a width of 35 mm, and a sheet of the intermediate layers 6 and 8 has a thickness of 8 mm and an apparent density of 35 kg, respectively. Using a cross-linked polyethylene foam of / m ³ processed to a width of 35 mm, a sheet of the outermost layer 10 of 2.5 mm thick and a cross-linked polyethylene foam of an apparent density of 35 kg / m ³ processed to a width of 35 mm, these The sheet was heat-sealed while being spirally wound around a core material 40 having an outer diameter of 11 mm, and further cut to obtain a cylindrical body 42 having an inner diameter of 12 mm, an outer diameter of 53 mm, and a length of 1000 mm. Next, in a state where the shaft center having an outer diameter of 11 mm is passed through the cylindrical body 42, a molding machine having an upper mold 44 and a lower mold 46 as shown in FIG. Corrugated molding was performed to produce four synthetic resin floats 2 having a length of 250 mm at a time.
(Example 3)
In the same manner as in Example 1, a synthetic resin floating body 2 having a four-layer structure was produced. In this case, a cross-linked polyethylene foam having a thickness of 2.5 mm and an apparent density of 100 kg / m ³ is processed as a sheet of the innermost layer 4 to a width of 35 mm, and sheets of the intermediate layers 6 and 8 are each 15 mm thick and an apparent density of 35 kg. / ^{m 3} of a cross-linked polyethylene foam which was processed into 35mm width, thickness 2.5 mm, a cross-linked polyethylene foam apparent density 30kg / ^{m 3} used as processed into 35mm width as a sheet of the outermost layer 10, these The sheet was heat-sealed while being spirally wound around a core material 40 having an outer diameter of 11 mm, and further cut to obtain a cylindrical body 42 having an inner diameter of 12 mm, an outer diameter of 52 mm, and a length of 1000 mm. Next, in a state where the shaft center having an outer diameter of 11 mm is passed through the cylindrical body 42, a molding machine having an upper mold 44 and a lower mold 46 as shown in FIG. A corrugated molding process was performed to produce five synthetic resin floats 2 having a length of 200 mm at a time.
Example 4
A synthetic resin float 22 having a structure as shown in FIG. 2 was produced. In this case, first, a cylindrical body 42 was formed by the method shown in FIG. 3 using a long sheet made of a synthetic resin foam. Specifically, a cross-linked polyethylene foam having a thickness of 3 mm and an apparent density of 100 kg / m ³ as a sheet of the innermost layer 24 is processed to a width of 25 mm, and a sheet of the intermediate layers 24 and 26 has a thickness of 8 mm and an apparent density of 35 kg, respectively. / ^{m 3} of a cross-linked polyethylene foam which was processed into 25mm width, those working thickness 3 mm, the cross-linked polyethylene foam apparent density 30kg / ^{m 3} to 25mm width as a sheet of the outermost layer 10, a sheet of the protective film 36 Using a non-crosslinked polyethylene film with a thickness of 50 μm processed to a width of 25 mm, these sheets are heat-sealed while spirally wound around a core material 40 with an outer diameter of 11 mm, and further cut to an inner diameter of 12 mm A cylindrical body 42 having an outer diameter of 54 mm and a length of 1000 mm was obtained. Next, in a state where a synthetic resin protective pipe 34 having an outer diameter of 12 mm passing through a shaft center having an outer diameter of 9 mm is inserted into the cylindrical body 42, a molding provided with an upper mold 44 and a lower mold 46 as shown in FIG. Using a machine, the outer surface of the cylindrical body 42 was subjected to corrugated molding by heat molding to produce four synthetic resin floats 2 having a length of 250 mm at a time.
(Comparative Example 1)
A synthetic resin levitation body having a multilayer structure was prepared. In this case, first, a cross-linked polyethylene foam having a thickness of 3 mm and an apparent density of 200 kg / m ³ was processed to a width of 25 mm as the innermost layer sheet, and a thickness of 5 mm and an apparent density of 200 kg / m3 as a three-layer intermediate sheet, respectively. m ³ cross-linked polyethylene foam processed to 25 mm width, outermost layer sheet 3 mm thick, apparent density 200 kg / m ³ cross-linked polyethylene foam processed to 25 mm width, protective film sheet thickness Using a 100 μm uncrosslinked polyethylene film processed to a width of 25 mm, these sheets are heat-sealed while spirally wound around a core material having an outer diameter of 11 mm, and further cut to give an inner diameter of 12 mm and an outer diameter of 54 mm. A cylinder with a length of 250 mm was obtained. Next, using a molding machine equipped with an upper mold 44 and a lower mold 46 as shown in FIG. 4 with a shaft having an outer diameter of 11 mm passed through the cylindrical body, the outer surface of the cylindrical body is corrugated by heat molding. The synthetic resin floating body of length 250mm was produced by giving a shaping | molding process.
(Comparative Example 2)
A synthetic resin levitation body having a multilayer structure was prepared. In this case, first, a cross-linked polyethylene foam having a thickness of 3 mm and an apparent density of 100 kg / m ³ was processed to a width of 25 mm as the innermost layer sheet, and the thickness of each of the three intermediate layers was 5 mm and the apparent density of 200 kg / those processed crosslinked polyethylene foam m ³ to 25mm width, thickness 3 mm, used as the cross-linked polyethylene foam apparent density 100 kg / ^{m 3} was processed into a width of 25mm, an outer diameter of these sheets as the outermost layer of the sheet It was heat-sealed while being spirally wound around an 11 mm core, and further cut to obtain a cylindrical body having an inner diameter of 12 mm, an outer diameter of 54 mm, and a length of 250 mm. Next, using a molding machine equipped with an upper mold 44 and a lower mold 46 as shown in FIG. 4 with a shaft having an outer diameter of 11 mm passed through the cylindrical body, the outer surface of the cylindrical body is corrugated by heat molding. The synthetic resin floating body of length 250mm was produced by giving a shaping | molding process.

The external appearance of the synthetic resin floating body of the said Example and the comparative example, the insertion property of a course rope, and the touch were evaluated. Evaluation methods and evaluation criteria were as follows. The results are shown in Table 1.
[appearance]
(Evaluation methods)
The external appearance of the obtained synthetic resin floating body was confirmed visually.
(Evaluation criteria)
◎: Good ○: Normal △: Wrinkled ×: Cracked [Coarse rope insertability]
(Evaluation methods)
A polyethylene pipe having a length of 1.0 m was vertically supported, and the obtained synthetic resin floating body was inserted from the upper end portion to evaluate the insertability. In Examples 1 to 3 and Comparative Examples 1 and 2, a pipe having a diameter of 10 mm was used, and in Example 4, a pipe having a diameter of 8 mm was used.
(Evaluation criteria)
A: Easily falls down.
○: It falls to the bottom while being caught.
X: Stops halfway.
[touch]
(Evaluation methods)
The touch of the obtained synthetic resin floating body was evaluated by tactile sensation.
(Evaluation criteria)
◎: Good ○: Normal △: Roughness ×: Hard

表１の結果より、最も内側の合成樹脂発泡体層を外傷に耐えうる高密度の合成樹脂発泡体層、中間の合成樹脂発泡体層を十分な浮力を保持しうる低密度の合成樹脂発泡体層、最も外側の合成樹脂発泡体層を肌触りのよい低密度の合成樹脂発泡体層とした実施例の合成樹脂浮揚体は、外傷防止、浮力および肌触りのいずれの点でも優れていることがわかる。

From the results in Table 1, a high-density synthetic resin foam layer that can withstand damage to the innermost synthetic resin foam layer and a low-density synthetic resin foam that can maintain sufficient buoyancy in the intermediate synthetic resin foam layer It can be seen that the synthetic resin floating body of the example in which the outermost synthetic resin foam layer is a low-density synthetic resin foam layer that is comfortable to touch is excellent in all aspects of prevention of trauma, buoyancy, and touch. .

It is a perspective view which shows an example of the synthetic resin floating body which concerns on this invention. It is sectional drawing which shows another example of the synthetic resin floating body which concerns on this invention. It is a perspective view which shows an example of the cylindrical body used for manufacture of a synthetic resin floating body. It is explanatory drawing which shows the state which gives a wave forming process to the outer surface of a cylindrical body by heat molding. It is a perspective view which shows another example of the cylindrical body used for manufacture of a synthetic resin floating body. It is a figure which shows the state which attached the floater to the course rope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Synthetic resin floating body 4 Synthetic resin foam layer 6 Synthetic resin foam layer 8 Synthetic resin foam layer 10 Synthetic resin foam layer 12 Cylindrical part 22 Synthetic resin floating body 24 Synthetic resin foam layer 26 Synthetic resin foam layer 28 Synthetic resin foam layer 30 Synthetic resin foam layer 34 Protective pipe 36 Protective film 40 Core material 42 Cylindrical body 44 Upper mold 46 Lower mold 50 Inner layer sheet 52 Side edge 54 Intermediate sheet 56 Side edge 58 Outer sheet 60 Side edge Part 62 cylindrical body 70 course rope 72 floater

Claims (7)

  A levitation body including a tubular portion having buoyancy, wherein the tubular portion has a multilayer structure in which a plurality of synthetic resin foam layers are laminated, and of the plurality of synthetic resin foam layers. The innermost synthetic resin foam layer is a high-density synthetic resin foam layer that can withstand trauma, and at least one of the outer synthetic resin foam layers can maintain a sufficient buoyancy. A synthetic resin floating body characterized by being a foam layer.   2. The synthetic resin float according to claim 1, wherein the outer surface is corrugated and molded.   The synthetic resin floating body according to claim 1 or 2, wherein each of the plurality of synthetic resin foam layers is made of a synthetic resin foam having a closed cell structure. 4. The synthesis according to claim 1, wherein an apparent density of the high-density synthetic resin foam layer capable of withstanding the wound is 50 to 200 kg / m ^3. Resin floater. The apparent density of the low-density synthetic resin foam layer capable of maintaining sufficient buoyancy is 18 to 50 kg / m ³ , The claim 1 according to any one of claims 1 to 4, The synthetic resin floating body described.   The cylindrical portion is formed in a cylindrical shape by winding a long sheet made of a synthetic resin foam in a spiral shape, and spirals a long sheet made of one or more synthetic resin foams around it. The synthetic resin floating body according to any one of claims 1 to 5, which has a structure in which a corrugated forming process is performed on an outer surface of a cylindrical body that is wound into a cylindrical shape. The cylindrical portion is formed by winding a rectangular sheet made of a synthetic resin foam into a cylindrical shape with its side edges abutting, and a rectangular sheet made of one or more synthetic resin foams around the cylindrical sheet. 6. The structure according to claim 1, wherein the outer surface of a cylindrical body formed in a cylindrical shape with its side edge portions in contact with each other is subjected to a corrugated molding process. The synthetic resin floating body as described in the item.

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