Patent Description:
In a related-art rope on a hoisting machine, which uses reinforcement fibers, a load bearing portion is made of a polymer matrix and the reinforcement fibers. As the reinforcement fibers, carbon fibers or glass fibers are used. Further, the reinforcement fibers are evenly dispersed in the polymer matrix, and are arranged in parallel to a longitudinal direction of the rope (for example, see Patent Literature <NUM>).

The above-mentioned rope using the reinforcement fibers has higher breaking strength per weight than a wire rope formed by twisting steel wires. Accordingly, particularly in a high-rise elevator requiring a long rope, a weight of the entire rope can be reduced, and a burden of driving on the hoisting machine can be reduced.

PTL <NUM> is considered relevant for the background art of the present invention and relates to a load bearing member is provided including at least one load bearing segment having a plurality of load carrying fibers arranged within a matrix material. At least a portion of the load bearing member has a radius of curvature when the load bearing member is untensioned.

However, the related-art ropes described above are poor in flexibility. Thus, it is difficult to bend a related-art rope along a driving sheave of the hoisting machine. Moreover, the bending may cause increase in internal stress of the rope, and hence there is a risk of causing breakage of the rope. In order to avoid such a breakage of the rope, it is necessary to increase a diameter of the driving sheave.

This invention has been made to solve the above-mentioned problem, and has an object to obtain an elevator capable of reducing stress generated on a load bearing layer of a suspension body when the suspension body is bent, a suspension body for the elevator, and a manufacturing method for such a suspension body.

The present invention is a suspension body according to independent claim <NUM> as enclosed. The present invention also relates to a manufacturing method for a suspension body according to the independent method claim as enclosed. Advantageous further developments of the invention are set forth in the dependent claims.

According to the elevator, the suspension body for an elevator, and the manufacturing method for the suspension body of this invention, there can be reduced stress generated on the load bearing layer of the suspension body when the suspension body is bent.

Now, the best mode for carrying out the present invention is described referring to the drawings.

<FIG> is a configuration view for illustrating an elevator according to a first example not according to the claimed invention. In <FIG>, a machine room <NUM> is provided in an upper part of a hoistway <NUM>. A hoisting machine <NUM>, a deflector sheave <NUM>, and an elevator controller <NUM> are installed in the machine room <NUM>. The hoisting machine <NUM> includes a driving sheave <NUM>, a hoisting machine motor (not shown) configured to rotate the driving sheave <NUM>, and a hoisting machine brake (not shown) configured to brake rotation of the driving sheave <NUM>.

A plurality of suspension bodies <NUM> (only one suspension body is illustrated in <FIG>) are wound around the driving sheave <NUM> and the deflector sheave <NUM>. The suspension bodies <NUM> each have a first end portion 7a and a second end portion 7b. The first end portion 7a is connected to a car <NUM> serving as an ascending/descending body. The second end portion 7b is connected to a counterweight <NUM> serving as an ascending/descending body.

The car <NUM> and the counterweight <NUM> are suspended by the suspension bodies <NUM> through use of a <NUM>:<NUM> roping method. Further, the car <NUM> and the counterweight <NUM> are vertically moved in the hoistway <NUM> through rotation of the driving sheave <NUM>. The elevator controller <NUM> is configured to control the hoisting machine <NUM>, to thereby control operation of the car <NUM>.

A pair of car guide rails (not shown) and a pair of counterweight guide rails (not shown) are installed in the hoistway <NUM>. The car guide rails are configured to guide vertical movement of the car <NUM>. The counterweight guide rails are configured to guide vertical movement of the counterweight <NUM>.

The car <NUM> includes a car frame <NUM> and a cage <NUM>. The suspension bodies <NUM> are connected to the car frame <NUM>. The cage <NUM> is supported by the car frame <NUM>.

<FIG> is a sectional view for schematically illustrating a cross section of the suspension body <NUM> in <FIG> perpendicular to a length direction thereof (Z-axis direction in <FIG>). The suspension body <NUM> has such a belt-like shape that a dimension in a thickness direction of the suspension body <NUM> (Y-axis direction in <FIG>) is smaller than a dimension in a width direction of the suspension body <NUM> (X-axis direction in <FIG>). That is, the suspension body <NUM> is a so-called flat belt.

Further, the suspension body <NUM> has a sheave contact surface 7c being any one of end surfaces in the thickness direction. When the suspension body <NUM> is wound around the driving sheave <NUM>, the sheave contact surface 7c is brought into contact with an outer peripheral surface of the driving sheave <NUM>. That is, when passing over the driving sheave <NUM>, the suspension body <NUM> is bent along the outer peripheral surface of the driving sheave <NUM> so that the sheave contact surface 7c is positioned on an inner side of the suspension body <NUM>.

The suspension body <NUM> includes a core <NUM> and a covering layer <NUM>. The core <NUM> has a belt-like shape. The covering layer <NUM> covers an entire periphery of the core <NUM>.

As a material for the covering layer <NUM>, a thermoplastic resin, such as polyethylene, polypropylene, polyamide <NUM> (PA6), polyamide <NUM> (PA12), polyamide <NUM> (PA66), polycarbonate, polyether ether ketone, or polyphenylene sulfide, may be used.

In addition, as a material for the covering layer <NUM>, an olefin-based, styrene-based, vinyl chloride-based, urethane-based, polyester-based, polyamide-based, fluorine-based, or butadiene-based thermoplastic elastomer may also be used.

Further, as a material for the covering layer <NUM>, a thermosetting elastomer (rubber), such as a butadiene rubber, a styrene-butadiene rubber, a chloroprene rubber, an acrylic rubber, a urethane rubber, or a silicone rubber, may also be used.

Further, as a material for the covering layer <NUM>, a carbon fiber, a glass fiber, an aramid fiber, a PBO (poly-p-phenylene benzobisoxazole) fiber, or a basalt fiber may be used. In addition, the material may be a composite material of a fiber and a resin.

It is preferred that a material having high heat resistance and high wear resistance be employed as a material for the covering layer <NUM>. Through change of the material for the covering layer <NUM>, a coefficient of friction between the suspension body <NUM> and the driving sheave <NUM> can be adjusted.

The core <NUM> includes a load bearing layer <NUM> and a plurality of intermediate layers <NUM>. The load bearing layer <NUM> is divided into a plurality of layers in the thickness direction of the core <NUM>, namely, the thickness direction of the suspension body <NUM>. That is, the load bearing layer <NUM> is formed of a plurality of segment layers <NUM> arranged apart from each other in the thickness direction of the core <NUM>.

The intermediate layer <NUM> is made of a material different from materials for the covering layer <NUM> and the load bearing layer <NUM>. Further, the intermediate layer <NUM> is interposed between the segment layers <NUM> adjacent to each other in the thickness direction of the core <NUM>. That is, the segment layers <NUM> and the intermediate layers <NUM> are alternately laminated in the thickness direction of the core <NUM>. In this example, the load bearing layer <NUM> is divided into three segment layers <NUM>. Thus, two intermediate layers <NUM> are used.

Further, the intermediate layer <NUM> may be interposed in an entire region between the segment layers <NUM> adjacent to each other in the thickness direction of the core <NUM>, or may be interposed only in a bent region. With this configuration, the adjacent segment layers <NUM> are not held in direct contact with each other, and the covering layer <NUM> does not enter the region between the adjacent segment layers <NUM>.

The load bearing layer <NUM> is a layer configured to mainly bear a load acting on the suspension body <NUM>. Further, the load bearing layer <NUM> is formed of an impregnation resin and a high-strength fiber group provided in the impregnation resin.

The high-strength fiber group includes a plurality of high-strength fibers arranged along the length direction of the core <NUM> (Z-axis direction in <FIG>). Further, the high-strength fiber group may be a high-strength fiber fabric or a high-strength fiber braid formed of the high-strength fibers arranged along the length direction of the core <NUM>.

The high-strength fiber is a light-weight and high-strength fiber. As the high-strength fiber, for example, a carbon fiber, a glass fiber, an aramid fiber, a PBO (poly-p-phenylene benzobisoxazole) fiber, or a basalt fiber may be used. In addition, as the high-strength fiber, a composite fiber obtained by combining those fibers may be used.

As the impregnation resin of the load bearing layer <NUM>, a thermosetting resin, such as polyurethane, an epoxy, an unsaturated polyester, vinyl ester, phenol, or silicone, may be used.

In addition, as the impregnation resin, a thermoplastic resin, such as polyethylene, polypropylene, polyamide <NUM> (PA6), polyamide <NUM> (PA12), polyamide <NUM> (PA66), polycarbonate, polyether ether ketone, or polyphenylene sulfide, may be used.

Moreover, the impregnation resin may contain a lubricant such as grease or oil. Alternatively, a lubricant such as grease may be used instead of the impregnation resin.

In particular, it is preferred that the impregnation resin be a resin having good adhesiveness with respect to the high-strength fibers. When a resin having a low modulus of elasticity is used as the impregnation resin, flexural rigidity of the suspension body <NUM> can be further reduced. Meanwhile, when a resin having a high modulus of elasticity is used as the impregnation resin, the high-strength fibers are firmly integrated together, thereby being capable of reducing unevenness in strength of the suspension body <NUM>.

Shear rigidity of the intermediate layer <NUM> is lower than shear rigidity of the segment layer <NUM>. As a material for the intermediate layer <NUM>, a thermosetting resin, such as polyurethane, an epoxy, an unsaturated polyester, a vinyl ester, phenol, or silicone, may be used.

In addition, as a material for the intermediate layer <NUM>, a thermoplastic resin, such as polyethylene, polypropylene, polyamide <NUM> (PA6), polyamide <NUM> (PA12), polyamide <NUM> (PA66), polycarbonate, polyether ether ketone, or polyphenylene sulfide, may also be used.

In the suspension body <NUM> for an elevator described above, the load bearing layer <NUM> is divided in the thickness direction of the core <NUM>, and the intermediate layer <NUM> is interposed between the adjacent segment layers <NUM>. Thus, through selection of a material for the intermediate layer <NUM>, bendability of the core <NUM> can be improved. Further, it is possible to relieve stress on the segment layers <NUM>, which are respectively located at an innermost layer and an outermost layer, when the core <NUM> is bent. With this configuration, a diameter of the driving sheave <NUM> can also be reduced.

Further, the shear rigidity of the intermediate layer <NUM> is set lower than the shear rigidity of the segment layer <NUM>. Thus, when the core <NUM> is bent, the intermediate layers <NUM> are easily deformed in a shearing direction (Z-axis direction in <FIG>). With this configuration, it is possible to more reliably relieve the stress on the segment layers <NUM>, which are respectively located at the innermost layer and the outermost layer, when the core <NUM> is bent.

<FIG> is a sectional view for illustrating a bent state of a piece of the suspension body <NUM> having the sectional structure in <FIG>, and illustrating a cross section (YZ cross section) of the suspension body <NUM> taken along the length direction. Further, <FIG> is an enlarged sectional view for illustrating a portion IV in <FIG>. As illustrated in <FIG>, when the suspension body <NUM> is bent, the intermediate layers <NUM> undergo shear deformation in the length direction of the core <NUM>, thereby improving flexibility of the suspension body <NUM>.

The number of the segment layers <NUM> is not limited to three. For example, as illustrated in <FIG>, the number of the segment layers <NUM> may be four. That is, the number of the segment layers <NUM> may be any number equal to or more than two. When the number of the segment layers <NUM> is set to n, the number of the intermediate layers <NUM> is n-<NUM>.

Further, it is desired that a modulus of rigidity of the intermediate layer <NUM> be set lower than a modulus of rigidity of the covering layer <NUM>. With this configuration, the region between the segment layers <NUM> more easily undergoes shear deformation, thereby further improving the flexibility of the suspension body <NUM>. Further, stress generated on the load bearing layer <NUM> when the core <NUM> is bent can be further reduced.

Moreover, in a case in which compression stiffness of a material for the intermediate layer <NUM> is set lower than compression stiffness of a material for the load bearing layer <NUM>, when the suspension body <NUM> passes over the driving sheave <NUM>, the suspension body <NUM> receives a load in a direction of compressing the cross section, and a thickness of the portion having received the compressive load is reduced. As a result, the suspension body <NUM> is easily bent.

Further, the intermediate layer <NUM> may be formed of an elastomer material having a characteristic, that is, a lower elastic modulus than that of the dividing layer <NUM>. As the elastomer material, for example, an olefin-based, styrene-based, vinyl chloride-based, urethane-based, polyester-based, polyamide-based, fluorine-based, or butadiene-based thermoplastic elastomer may be used. In addition, as the elastomer material, a thermosetting elastomer (rubber), such as a butadiene rubber, a styrene-butadiene rubber, a chloroprene rubber, an acrylic rubber, a urethane rubber, or a silicone rubber, may be used.

Further, as a material for the intermediate layer <NUM>, there may be used a polymer gel having intermediate properties between a solid and a liquid.

Moreover, as a material for the intermediate layer <NUM>, there may be used a lubricant such as a liquid lubricant, a semi-solid lubricant, or a solid lubricant. As the liquid lubricant, for example, a lubricating oil is given. An example of the semi-solid lubricant is grease. Examples of the solid lubricant include graphite, tungsten disulfide, molybdenum disulfide, and polytetrafluoroethylene.

Further, the intermediate layer <NUM> may be formed of a low-friction sheet which is not bonded to the load bearing layer <NUM>. As the sheet, for example, an olefin-based sheet, a fluorine-based sheet, a polyester-based sheet, or a polyamide-based sheet may be used.

As a material for the olefin-based sheet, there is given, for example, polyethylene or polypropylene. As a material for the fluorine-based sheet, there is given, for example, polytetrafluoroethylene. As a material for the polyester-based sheet, there is given, for example, polyethylene terephthalate. As a material for the polyamide-based sheet, there is given, for example, polyamide <NUM>.

Further, a plurality of sheets can be arranged in layers. Moreover, the liquid lubricant, the semi-solid lubricant, and the solid lubricant can be used in combination. For example, a configuration in which the liquid lubricant is arranged on a surface of the sheet of the solid lubricant is conceivable. Through use of such a lubricant, shear resistance in the intermediate layer <NUM> can be reduced, thereby improving the flexibility of the suspension body <NUM>.

Moreover, as a material for the intermediate layer <NUM>, there may be used a material that is more flexible and richer in cushioning property in the compressing direction than the material of the segment layer <NUM>. An example of such material includes a polymer foam. Examples of the polymer foam include a polyurethane foam, a polyethylene foam, a polyethylene terephthalate foam, a polypropylene foam, an acrylic foam, a polystyrene foam, a phenol foam, a silicone foam, and an EVA foam.

Through use of the above-mentioned material that is rich in cushioning property in the compressing direction, vibration and a shock during operation of the car <NUM> can be absorbed. Further, when the suspension body <NUM> receives tension, a portion of the suspension body <NUM> held in contact with the driving sheave <NUM> is compressed in the thickness direction, and the thickness of the contact portion is reduced. As a result, the suspension body <NUM> is easily bent and deformed.

Further, the intermediate layer <NUM> may be formed of fibers (hereinafter referred to as "intermediate-layer fibers"). It is preferred that a form of the intermediate-layer fibers in this case be continuous fibers continuous in the length direction of the core <NUM>, but the form of the intermediate-layer fibers may be long fibers or short fibers. When the intermediate-layer fibers are placed in the intermediate layer <NUM>, deformation of the intermediate layer <NUM> in the compressing direction, namely, the thickness direction can be suppressed, thereby being capable of relieving stress concentration caused by bending of the segment layer <NUM> at the time of reception of the compressive load.

Moreover, when the intermediate-layer fibers are placed in the intermediate layer <NUM>, it is preferred that a fiber density or modulus of elasticity of the intermediate-layer fibers, which are arranged in the intermediate layer <NUM> along the length direction of the core <NUM>, be set lower than a fiber density or modulus of elasticity of the high-strength fibers, which are arranged in the load bearing layer <NUM> along the length direction of the core <NUM>.

With this configuration, the flexural rigidity of the intermediate layer <NUM> in the length direction of the core <NUM> can be set lower than that of the load bearing layer <NUM> while suppressing compressive deformation of the intermediate layer <NUM>, thereby improving the flexibility of the suspension body <NUM>.

As a method of reducing a fiber density, for example, there is given a method of reducing a fiber diameter or a method of reducing a content of fibers. As a method of reducing a modulus of elasticity of fibers, for example, there is given a method of using glass fibers, polyester fibers, polyarylate fibers, polyethylene fibers, or aramid fibers as the intermediate-layer fibers when the high-strength fibers in the load bearing layer <NUM> are carbon fibers.

Further, when the intermediate-layer fibers are placed in the intermediate layer <NUM>, the intermediate-layer fibers may include inclined fibers inclined with respect to the length direction of the core <NUM>, for example, inclined at <NUM> degrees. With this configuration, the rigidity against torsion can be improved while reducing the rigidity against bending in the length direction of the core <NUM>.

Moreover, when the intermediate-layer fibers are placed in the intermediate layer <NUM>, the intermediate-layer fibers may include orthogonal fibers arranged along a direction orthogonal to the length direction of the core <NUM>, that is, along the width direction of the suspension body <NUM>. With this configuration, the flexural rigidity in the width direction of the core <NUM> can be improved while reducing the rigidity against bending in the length direction of the core <NUM>.

Moreover, the load bearing layer <NUM> in the first example may be formed of the high-strength fiber group without the impregnation resin. With this configuration, the flexural rigidity can be further reduced.

Further, the covering layer <NUM> may contain the lubricant.

Moreover, a portion including the lubricant and a portion without the lubricant may be provided depending on positions in the length direction for each of the covering layer <NUM>, the load bearing layer <NUM>, and the intermediate layer <NUM>.

Next, <FIG> is a sectional view for illustrating the suspension body <NUM> for an elevator according to a second example not according to the claimed invention. In the second example, the same intermediate layer <NUM> as that in the first example is interposed between the outermost layer <NUM> and the intermediate bearing layer <NUM> and between the innermost layer <NUM> and the intermediate bearing layer <NUM>. That is, the outermost layer <NUM>, the innermost layer <NUM>, and the intermediate bearing layer <NUM> can be considered as the segment layers <NUM> in the first example, respectively.

In the above-mentioned suspension body <NUM>, as described in the first example, the intermediate layers <NUM> are easily deformed in the shearing direction, thereby further improving the flexibility in the length direction of the core <NUM>. In particular, through use of the intermediate layers <NUM> made of a material having low shear rigidity, when the suspension body <NUM> is bent, stress generated on the load bearing layer <NUM> can be further relieved.

Next, <FIG> is a sectional view for illustrating the suspension body <NUM> for an elevator according to a third example not according to the claimed invention. In the third example, similarly to the second example, the load bearing layer <NUM> is formed of a plurality of layers divided in the thickness direction of the core, that is, the outermost layer <NUM>, the innermost layer <NUM>, and the intermediate bearing layer <NUM>. However, the flexural rigidity of the outermost layer <NUM> and the flexural rigidity of the innermost layer <NUM> are different from each other.

In the third example, the flexural rigidity of the outermost layer <NUM> is lower than the flexural rigidity of the other layers forming the load bearing layer <NUM>, that is, the flexural rigidity of the innermost layer <NUM> and the intermediate bearing layer <NUM>. The flexural rigidity of the innermost layer <NUM> is lower than the flexural rigidity of the intermediate bearing layer <NUM>, or equal to the flexural rigidity of the intermediate bearing layer <NUM>.

As a method of making a difference in rigidity between the outermost layer <NUM> and the innermost layer <NUM>, the following method is given. For example, by setting the density of the high-strength fibers in the outermost layer <NUM> lower than the density of the high-strength fibers in each of the innermost layer <NUM> and the intermediate bearing layer <NUM>, the flexural rigidity of the outermost layer <NUM> can be set lower than the flexural rigidity of the innermost layer <NUM> and the intermediate bearing layer <NUM>.

Further, also by setting the modulus of elasticity of the outermost layer <NUM> lower than the modulus of elasticity of each of the innermost layer <NUM> and the intermediate bearing layer <NUM>, the flexural rigidity of the outermost layer <NUM> can be set lower than the flexural rigidity of the innermost layer <NUM> and the intermediate bearing layer <NUM>. The other configurations are the same as those of the second example.

In the above-mentioned suspension body <NUM>, when the suspension body <NUM> is wound around the driving sheave <NUM>, stress generated on the outermost layer <NUM> can be reduced. Further, there is a difference in rigidity between one side and another side of the core <NUM> in the thickness direction, and hence the suspension body <NUM> is easily bent when being wound around the driving sheave <NUM>. Moreover, when the suspension body <NUM> receives the compressive load in the length direction from, for example, the hoisting machine brake, the suspension body <NUM> can be easily bent in one direction.

<FIG> is a sectional view for illustrating a state during manufacture of the suspension body <NUM> for an elevator according to a fourth example not according to the claimed invention, and illustrating a cross section corresponding to the cross section of the suspension body <NUM> perpendicular to the length direction thereof. In the manufacturing method according to the fourth example, a plurality of high-strength fiber layers <NUM> and at least one low-elasticity fiber layer <NUM> are alternately laminated in the thickness direction of the suspension body to form a laminated body <NUM>.

<FIG> is a partial enlarged sectional view for illustrating the high-strength fiber layer <NUM> in <FIG>. Each high-strength fiber layer <NUM> is formed by laminating a plurality of high-strength fiber fabrics <NUM> formed of the high-strength fibers as described in the first example. The high-strength fiber layer <NUM> may be formed of only a single high-strength fiber fabric <NUM>.

Each high-strength fiber fabric <NUM> is a unidirectional fiber fabric obtained by providing wefts <NUM> passing over and under high-strength fiber threads <NUM> shaped into a plurality of bundles. The wefts <NUM> may be made of any kinds of fibers. Further, in <FIG>, an aligned state of the high-strength fiber threads <NUM> is illustrated, but the high-strength fiber threads <NUM> may be staggered.

The low-elasticity fiber layer <NUM> is formed by laminating a plurality of low-elasticity fiber fabrics having a modulus of elasticity lower than that of the high-strength fiber fabric <NUM>. The low-elasticity fiber layer <NUM> may be formed of only a single low-elasticity fiber fabric.

As fibers to be used for the low-elasticity fiber fabric, namely, the intermediate-layer fibers in the fourth example, glass fibers or polyester fibers are exemplified. Further, a form of the low-elasticity fiber fabric is, for example, a fabric, a nonwoven fabric, or a knitted fabric.

<FIG> is a schematic configuration view for illustrating a first manufacturing apparatus for the suspension body <NUM> according to the fourth example, which is an apparatus configured to manufacture the core <NUM> in the first example. The manufacturing apparatus in <FIG> includes a laminating unit <NUM>, a resin bath <NUM>, a hot forming device <NUM>, a drawing device <NUM>, and a reeling device <NUM>. In <FIG>, for ease of description, only two high-strength fiber layers <NUM> and one low-elasticity fiber layer <NUM> are illustrated.

The high-strength fiber layers <NUM> and the low-elasticity fiber layer <NUM> unwound from rolls are laminated in the laminating unit <NUM> so as to form the laminated body <NUM>. Lamination of the high-strength fiber fabrics <NUM> forming each high-strength fiber layer <NUM>, and lamination of the low-elasticity fiber fabrics forming each low-elasticity fiber layer <NUM> may be performed in the laminating unit <NUM>.

The laminated body <NUM> formed in the laminating unit <NUM> is drawn into the resin bath <NUM> by the drawing device <NUM>. The resin bath <NUM> contains an uncured thermosetting resin. As thermosetting resin, thermosetting resin to be used for the intermediate layers <NUM> and the segment layers <NUM> in the first example is used. In the resin bath <NUM>, the uncured thermosetting resin is impregnated into the laminated body <NUM>. It is required that narrow spaces between fibers be impregnated with thermosetting resin, and hence it is desired that thermosetting resin in the resin bath <NUM> have low viscosity.

After that, the laminated body <NUM> is drawn into the hot forming device <NUM> by the drawing device <NUM>. In the hot forming device <NUM>, the laminated body <NUM> is heated so that thermosetting resin is cured. In this manner, the high-strength fiber layers <NUM> and the low-elasticity fiber layer <NUM> are integrated with each other, thereby forming the core <NUM> in the first example. The core <NUM> is reeled by the reeling device <NUM>.

<FIG> is a sectional view for illustrating the core <NUM> of the suspension body <NUM> manufactured by the first manufacturing apparatus in <FIG>, and illustrating the cross section of the core <NUM> perpendicular to the length direction. The segment layers <NUM> in the fourth example are each made of FRP (fiberglass reinforced plastics) including the high-strength fiber fabric <NUM>. Further, the intermediate layers <NUM> are each made of the FRP including the low-elasticity fiber fabric. Moreover, a resin forming the segment layers <NUM> is the same as a resin forming the intermediate layers <NUM>.

The outer periphery of the core <NUM> illustrated in <FIG> is covered with the covering layer <NUM> made of a resin. Thus, the suspension body <NUM> is completed. As the resin forming the covering layer <NUM>, the resin exemplified in the first example can be used.

The covering layer <NUM> is formed by covering the outer periphery of the core <NUM> with a resin through continuous press forming, intermittent press forming, or laminate forming, and then trimming unnecessary portions.

<FIG> is a schematic configuration view for illustrating a second manufacturing apparatus for the suspension body <NUM> according to the fourth example, which is an apparatus configured to form the covering layer <NUM>. The second manufacturing apparatus includes a sheet arranging unit <NUM> and a pressure forming device <NUM>. In the sheet arranging unit <NUM>, a plurality of thermoplastic sheets <NUM>, which form the covering layer <NUM> and are made of a thermoplastic resin, are arranged so as to surround the core <NUM>.

After that, the core <NUM> and the thermoplastic sheets <NUM> are transferred to the pressure forming device <NUM> and are subjected to pressure forming. In <FIG>, a double belt press is illustrated as the pressure forming device <NUM>, but the pressure forming device <NUM> is not limited thereto. As long as pressure required for integration of the thermoplastic sheets <NUM> and the core <NUM> can be applied continuously or intermittently, for example, an intermittent press or a laminator may be employed.

<FIG> is a sectional view for illustrating a state in which the pressure forming device <NUM> in <FIG> applies pressure to the core <NUM> and the thermoplastic sheets <NUM>, and illustrating the cross section perpendicular to the length direction of the core <NUM>. The thermoplastic sheets <NUM> are arranged on both sides of the core <NUM> in the thickness direction (up-and-down direction in <FIG>) and on both sides of the core <NUM> in the width direction (right-and-left direction in <FIG>).

The pressure forming device <NUM> includes a pair of forming dies 63a and 63b configured to sandwich the core <NUM> and the thermoplastic sheets <NUM> from the both sides of the core <NUM> in the thickness direction. The forming dies 63a and 63b apply pressure in directions indicated by the arrows in <FIG>.

<FIG> is a sectional view for illustrating the suspension body <NUM>, which has not been completed, subjected to pressure forming by the pressure forming device <NUM> in <FIG>. After the suspension body <NUM> passes through the pressure forming device <NUM>, the covering layer <NUM> protrudes to the both sides of the suspension body <NUM> in the width direction more than necessary. Thus, the unnecessary portions are trimmed along the broken lines in <FIG>. In this manner, the suspension body <NUM> is completed.

According to this manufacturing method, the suspension body <NUM>, in which the load bearing layer <NUM> is divided in the thickness direction of the core <NUM> and the intermediate layer <NUM> is interposed between the adjacent segment layers <NUM>, can be easily manufactured. With this method, bendability of the core <NUM> can be improved, thereby being capable of relieving stress concentration on the segment layers <NUM>, which are respectively located at the innermost layer and the outermost layer.

Next, <FIG> is a sectional view for illustrating the suspension body for an elevator according to a first embodiment of this invention. <FIG> is an enlarged sectional view for illustrating a portion 101a in <FIG>. <FIG> is an enlarged sectional view for illustrating a portion 101b in <FIG>. The portion 101a in <FIG> is located at the center portion of the load bearing layer <NUM> in the thickness direction. Further, the portion 101b in <FIG> is located at the end portion of the load bearing layer <NUM> in the thickness direction.

The core <NUM> in the first embodiment includes only the load bearing layer <NUM>. The load bearing layer <NUM> is formed of an impregnation resin <NUM> and a plurality of high-strength fibers <NUM>. Further, a density of the high-strength fibers <NUM> in the center portion of the load bearing layer <NUM> in the thickness direction is higher than a density of the high-strength fibers <NUM> in each end portion of the load bearing layer <NUM> in the thickness direction.

In all of the embodiments, the density of the high-strength fibers <NUM> means a ratio of the high-strength fibers forming the load bearing layer <NUM>. That is, a volume content of the high-strength fibers <NUM> forming a fixed amount of the load bearing layer <NUM>, or a ratio of a sectional area of the high-strength fibers <NUM> occupying the cross section perpendicular to the length direction of the core <NUM> corresponds to the density of the high-strength fibers <NUM>.

In the first embodiment, the density of the high-strength fibers <NUM> decreases continuously from the center portion of the load bearing layer <NUM> in the thickness direction toward both end portions of the load bearing layer <NUM> in the thickness direction. Further, in the first embodiment, through variation of the number of the high-strength fibers <NUM> occupying the sectional area perpendicular to the length direction of the core <NUM>, the density of the high-strength fibers <NUM> is varied. The other configurations are the same as those of the third example.

Here, tensile rigidity of the high-strength fibers <NUM> in the Z-axis direction is higher than tensile rigidity of the impregnation resin <NUM> in the Z-axis direction. This is because, in the entire FRP, the high-strength fibers <NUM> mainly have a function of increasing strength and rigidity, and the impregnation resin <NUM> mainly has a function of integrating the high-strength fibers <NUM>.

The load bearing layer <NUM> in this embodiment is characterized in that tensile rigidity in the Z-axis direction is high at the center portion in the Y-axis direction, and that the tensile rigidity decreases at a portion farther from the center portion in the Y-axis direction. Thus, when the cross section of the load bearing layer <NUM> is the same shape and a content of the high-strength fibers <NUM> is the same, a sectional secondary moment in bending with respect to the X-axis, namely, bending about the X-axis becomes lower as compared to a case in which the high-strength fibers <NUM> are evenly dispersed in the impregnation resin <NUM>.

With this configuration, the suspension body is easily bent with respect to the X-axis, and a winding start portion and a winding end portion of the suspension body wound around the driving sheave <NUM> are less liable to loosen up. Thus, the suspension body is less liable to slip off the driving sheave <NUM> when the suspension body is transferred by the driving sheave <NUM>.

Further, it is desired that, in the load bearing layer <NUM> in the first embodiment, the center portion of the load bearing layer <NUM> in the thickness direction be located close to a position on the neutral axis at which the suspension body is not subjected to compression and tension under a state in which the suspension body is wound around the driving sheave <NUM>. Thus, the tension acts on the suspension body in a state of being applied to the elevator, and hence it is desired that the center portion of the load bearing layer <NUM> be located on a side closer to a contact surface with the driving sheave <NUM> than to the center portion of the suspension body in the thickness direction.

Further, the contact surface of the suspension body with the driving sheave <NUM> can be increased, thereby being capable of increasing a transmittable drive force owing to a frictional force acting on the contact surface. Further, the suspension body is easily bent, and hence is easily handled during work such as storage, transport, installation, or replacement.

Here, the Young's modulus of the impregnation resin <NUM> affects readiness of bending of the entire load bearing layer <NUM>. That is, when the Young's modulus of the impregnation resin <NUM> is set low, the readiness of bending is improved. Ideally, it is preferred that the Young's modulus of the impregnation resin <NUM> be set equal to or lower than <NUM> GPa.

Meanwhile, when bending with respect to the X-axis is caused to act on the load bearing layer <NUM>, the high-strength fibers <NUM> are partially subjected to tension in the Z-axis direction, and are partially subjected to compression in the Z-axis direction. In contrast, when the Young's modulus of the impregnation resin <NUM> is set excessively low, the high-strength fibers <NUM> are easily moved in a direction perpendicular to the Z-axis direction in a case in which the high-strength fibers <NUM> are compressed.

Then, separation occurs between the high-strength fibers <NUM> and the impregnation resin <NUM>, with the result that a phenomenon of breakage of the load bearing layer <NUM> is liable to occur. Thus, it is desired that the Young's modulus of the impregnation resin <NUM> be set equal to or higher than <NUM> GPa.

As described above, it is preferred that the Young's modulus of the impregnation resin <NUM> be set equal to or lower than <NUM> GPa and equal to or higher than <NUM> GPa. In particular, as characteristics capable of properly balancing readiness of bending and unbreakableness, it is preferred to select the impregnation resin <NUM> having the Young's modulus of equal to or lower than <NUM> GPa, more preferably, the Young's modulus of equal to or lower than <NUM> GPa. This holds true for all other embodiments relating to the suspension body using the impregnation resin <NUM>.

Further, it is preferred that, in a portion of the load bearing layer <NUM> having the highest density of the high-strength fibers <NUM>, namely, the center portion of the load bearing layer <NUM> in the thickness direction, a volume content of the high-strength fibers <NUM> be set equal to or larger than <NUM> %, more preferably, equal to or larger than <NUM> %.

Further, it is preferred that, in a portion of the load bearing layer <NUM> having the lowest density of the high-strength fibers <NUM>, namely, each end portion of the load bearing layer <NUM> in the thickness direction, the volume content of the high-strength fibers <NUM> be set equal to or lower than <NUM> %, more preferably, equal to or lower than <NUM> %.

This is because, when the density of the high-strength fibers <NUM> is excessively high, the effect of integrating the high-strength fibers <NUM> by the impregnation resin <NUM> is reduced, with the result that fatigue due to bending is liable to progress. The center portion in the thickness direction, which is subjected to low stress when the core <NUM> is bent in a longitudinal direction thereof, is formed to have a high carbon fiber density enabling impregnation in manufacture. Meanwhile, the end portion, which is subjected to a large change in stress due to bending, is formed to have a carbon fiber density capable of sufficiently attaining the integrating effect. Thus, optimization of fatigue and strength can be achieved.

<FIG> is a schematic configuration view for illustrating a manufacturing apparatus for the suspension body according to this embodiment. <FIG> is a sectional view for illustrating a main part of <FIG>. In the apparatus in <FIG>, a first high-strength fiber group <NUM> and a plurality of second high-strength fiber groups <NUM> are paid out from corresponding bobbins, respectively. A fiber density of the first high-strength fiber group <NUM> is higher than a fiber density of the second high-strength fiber groups <NUM>.

In <FIG>, for ease of description, the two kinds of high-strength fiber groups <NUM> and <NUM> are illustrated. However, more bobbins may be arranged, and three or more kinds of high-strength fiber groups different in fiber density may be paid out. In this manner, the density of the high-strength fibers <NUM> can be continuously varied.

The high-strength fiber groups <NUM> and <NUM> paid out from the bobbins are caused to pass through a fiber positioning unit <NUM>. As illustrated in <FIG>, the fiber positioning unit <NUM> has a plurality of holes 110b configured to allow individual passage of the high-strength fiber groups <NUM> and <NUM>. A guide wall 110a configured to guide the high-strength fiber group <NUM> individually is formed around each of the holes 110b.

The high-strength fiber groups <NUM> and <NUM> are caused to pass through the fiber positioning unit <NUM>, and thus are brought close to each other while maintaining mutual relative positions. Further, the high-strength fiber groups <NUM> and <NUM> are caused to pass through an injection device <NUM> after passing through the fiber positioning unit <NUM>.

In the injection device <NUM>, the impregnation resin <NUM> is impregnated into a bundle of the high-strength fiber groups <NUM> and <NUM>. The other configurations of the manufacturing apparatus and the other processes of the manufacturing method are the same as those of the fourth example.

As described above, the manufacturing method for the suspension body according to the first embodiment includes first to fifth steps. The first step is a step of paying out the plurality of high-strength fiber groups <NUM> and <NUM> different in fiber density from the corresponding bobbins, respectively. The second step is a step of forming the bundle of the high-strength fiber groups <NUM> and <NUM> by bringing the high-strength fiber groups <NUM> and <NUM> close to each other while maintaining the mutual relative positions.

The third step is a step of impregnating the impregnation resin <NUM> into the bundle of the high-strength fiber groups <NUM> and <NUM>. The fourth step is a step of forming the core <NUM> by performing hot forming on the bundle of the high-strength fiber groups <NUM> and <NUM> impregnated with a resin. The fifth step is a step of forming the covering layer <NUM> covering at least a part of the outer periphery of the core <NUM>.

With this manufacturing method, the suspension body having the sectional structure as illustrated in <FIG> can be efficiently manufactured.

Next, <FIG> is an enlarged sectional view for illustrating the center portion of the load bearing layer <NUM> in the thickness direction according to a fifth example not according to the claimed invention. <FIG> is an enlarged sectional view for illustrating the end portion of the load bearing layer <NUM> in the thickness direction according to the fifth example. <FIG> is an illustration of a portion corresponding to the portion 101a in <FIG>. <FIG> is an illustration of a portion corresponding to the portion 101b in <FIG>.

In the fifth example, a plurality of kinds of high-strength fibers <NUM> having different diameters are used. That is, as the high-strength fibers <NUM>, a plurality of first high-strength fibers 102a and a plurality of second high-strength fibers 102b are used. A diameter of the second high-strength fibers 102b is larger than a diameter of the first high-strength fibers 102a. A material for the second high-strength fibers 102b is the same as a material for the first high-strength fibers 102a.

In the center portion of the load bearing layer <NUM> in the thickness direction, the first high-strength fibers 102a are arranged among the second high-strength fibers 102b. In contrast, in each end portion of the load bearing layer <NUM> in the thickness direction, no first high-strength fibers 102a are arranged among the second high-strength fibers 102b, or the number of the first high-strength fibers 102a arranged among the second high-strength fibers 102b is reduced.

With this configuration, the density of the high-strength fibers <NUM> in the center portion of the load bearing layer <NUM> in the thickness direction is higher than the density of the high-strength fibers <NUM> in each end portion of the load bearing layer <NUM> in the thickness direction.

Further, through continuous variation of the number of the first high-strength fibers 102a along the thickness direction of the load bearing layer <NUM>, the density of the high-strength fibers <NUM> can be decreased continuously from the center portion of the load bearing layer <NUM> in the thickness direction toward each end portion of the load bearing layer <NUM> in the thickness direction. The other configurations are the same as those of the.

Further, when the load bearing layer <NUM> in the fifth example is manufactured, it is only required that the density of the first high-strength fibers 102a in the high-strength fiber groups <NUM> paid out from the upper and lower bobbins in <FIG> be set low, and that the density of the first high-strength fibers 102a in the high-strength fiber group <NUM> paid out from the center bobbin be set high.

Even with this configuration, the same effects as those of the first embodiment can be attained. Further, the high-strength fibers 102a and 102b having different sizes are used, and hence gathering of the high-strength fibers 102a and 102b is less liable to occur at the time of resin impregnation. Thus, a target density distribution can be achieved with better accuracy.

Next, <FIG> is a sectional view for illustrating the suspension body for an elevator according to a sixth example not according to the claimed invention. <FIG> is an enlarged sectional view for illustrating a portion 101c in <FIG>. <FIG> is an enlarged sectional view for illustrating a portion 101d in <FIG>. The portion 101c in <FIG> is located at the first end portion of the load bearing layer <NUM> in the thickness direction. Further, the portion 101d in <FIG> is located at the second end portion of the load bearing layer <NUM> in the thickness direction.

In the sixth example, the density of the high-strength fibers <NUM> in the first end portion of the load bearing layer <NUM> in the thickness direction is higher than the density of the high-strength fibers <NUM> in the second end portion of the load bearing layer <NUM> in the thickness direction. Further, the density of the high-strength fibers <NUM> decreases continuously from the first end portion toward the second end portion of the load bearing layer <NUM> in the thickness direction.

Further, it is preferred that, in a portion of the load bearing layer <NUM> having the highest density of the high-strength fibers <NUM>, namely, the first end portion of the load bearing layer <NUM> in the thickness direction, the volume content of the high-strength fibers <NUM> be set equal to or larger than <NUM> %, more preferably, equal to or larger than <NUM> %.

Further, it is preferred that, in a portion of the load bearing layer <NUM> having the lowest density of the high-strength fibers <NUM>, namely, the second end portion of the load bearing layer <NUM> in the thickness direction, the volume content of the high-strength fibers <NUM> be set equal to or smaller than <NUM> %, more preferably, equal to or smaller than <NUM> %. The other configurations and the other processes of the manufacturing method are the same as those of the first embodiment.

With regard to this suspension body, the neutral plane in the cross section under bending can be shifted, thereby being capable of improving readiness of bending.

In order to vary the density of the high-strength fibers <NUM> as described in the sixth example, the same method as that of the fifth example may be applied.

Next, <FIG> is a sectional view for illustrating the suspension body for an elevator according to a second embodiment of this invention. <FIG> is an enlarged sectional view for illustrating a portion 101e in <FIG>. The portion 101e in <FIG> is located at the end portion of the load bearing layer <NUM> in the thickness direction.

In the second embodiment, the density of the high-strength fibers <NUM> in the center portion of the load bearing layer <NUM> in the thickness direction is higher than the density of the high-strength fibers <NUM> in each end portion of the load bearing layer <NUM> in the thickness direction. Further, a layer including only the impregnation resin <NUM> is formed in each end portion of the load bearing layer <NUM> in the thickness direction. The other configurations and the other processes of the manufacturing method are the same as those of the first embodiment or the fifth example.

Even with this configuration of the suspension body, bendability can be improved. Further, the layer including only the impregnation resin <NUM> is present on the surface of the load bearing layer <NUM>, thereby being capable of improving adhesiveness with respect to the covering layer <NUM>. With this configuration, occurrence of separation between the load bearing layer <NUM> and the covering layer <NUM> due to bending can be suppressed.

The layer including only the impregnation resin <NUM> in the second embodiment may be formed in the second end portion in the sixth example.

Further, in a portion other than the layer including only the impregnation resin <NUM>, the density of the high-strength fibers <NUM> may be uniform in the thickness direction of the load bearing layer <NUM>.

Next, <FIG> is a sectional view for illustrating the suspension body for an elevator according to a third embodiment of this invention. <FIG> is an enlarged sectional view for illustrating a portion 101fin <FIG>. <FIG> is an enlarged sectional view for illustrating a portion <NUM> in <FIG>. The portion 101f in <FIG> is located at the center portion of the load bearing layer <NUM> in the width direction. Further, the portion <NUM> in <FIG> is located at the end portion of the load bearing layer <NUM> in the width direction.

In the third embodiment, the density of the high-strength fibers <NUM> in the center portion of the load bearing layer <NUM> in the width direction is higher than the density of the high-strength fibers <NUM> at each end portion of the load bearing layer <NUM> in the width direction. Further, the density of the high-strength fibers <NUM> decreases continuously from the center portion of the load bearing layer <NUM> in the width direction toward each end portion of the load bearing layer <NUM> in the width direction.

Further, it is preferred that, in a portion of the load bearing layer <NUM> having the highest density of the high-strength fibers <NUM>, namely, the center portion of the load bearing layer <NUM> in the width direction, a volume content of the high-strength fibers <NUM> be set equal to or larger than <NUM> %, more preferably, equal to or larger than <NUM> %.

Further, it is preferred that, in a portion of the load bearing layer <NUM> having the lowest density of the high-strength fibers <NUM>, namely, each end portion of the load bearing layer <NUM> in the width direction, the volume content of the high-strength fibers <NUM> be set equal to or smaller than <NUM> %, more preferably, equal to or smaller than <NUM> %. The other configurations and the other processes of the manufacturing method are the same as those of the first embodiment.

With regard to this suspension body, rigidity of both end portions of the core <NUM> in the width direction is low, and hence the core <NUM> is easily bent with respect to the Z-axis. As a result, adhesiveness with respect to the driving sheave <NUM> is improved.

The third embodiment may be combined with the first embodiment. That is, in the third embodiment, the density of the high-strength fibers <NUM> in each end portion of the load bearing layer <NUM> in the thickness direction may be set lower than the density of the high-strength fibers <NUM> in the center portion in the thickness direction.

Claim 1:
A suspension body (<NUM>) for an elevator, comprising:
a core (<NUM>) having a belt-like shape and including a load bearing layer (<NUM>) formed of an impregnation resin (<NUM>) and a plurality of high-strength fibers (<NUM>); and
a covering layer (<NUM>) covering at least a part of an outer periphery of the core (<NUM>), wherein either:
a) a density of the high-strength fibers (<NUM>) in a center portion of the load bearing layer (<NUM>) in a thickness direction of the load bearing layer (<NUM>) is higher than a density of the high-strength fibers (<NUM>) in both end portions of the load bearing layer (<NUM>) in the thickness direction, or
b) a density of the high-strength fibers (<NUM>) in a center portion of the load bearing layer (<NUM>) in a width direction of the load bearing layer (<NUM>) is higher than a density of the high-strength fibers (<NUM>) in both end portions of the load bearing layer (<NUM>) in the width direction.