EP1312574B1

EP1312574B1 - Synthetic fiber rope for elevators

Info

Publication number: EP1312574B1
Application number: EP00954956A
Authority: EP
Inventors: Atsushi Mitsubishi Denki K.K. MITSUI
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2000-08-24
Filing date: 2000-08-24
Publication date: 2012-03-07
Anticipated expiration: 2020-08-24
Also published as: EP1312574A4; EP1312574A1; CN1376133A; CN1184132C; WO2002016249A1; KR20020037373A; KR100479152B1; JP4640907B2

Abstract

A synthetic fiber rope having an armor cover layer (3) formed of flexible synthetic resin to cover the outer peripheries of a plurality of strands (2) of synthetic fiber constituting the outer peripheral side of the synthetic fiber rope. And the position of the cab in the elevator shaft is pre-set by one colored region of the armor cover layer (3) lengthwise of the synthetic fiber rope, on the basis of the relationship between the colored region and the sheave having the main rope entrained therearound, so as to provide the synthetic fiber rope with a position index function. This makes the index to be easily identified even after the long-term use of the elevator, excluding defective conditions caused by the index becoming unidentifiable due to wear with time or the like. Therefore, it is possible to properly cope with operations for rescuing passengers from the cab during accidental stoppage and to speed up rescue operations.

Description

Technical Field

The present invention relates to a synthetic fiber rope which is coiled around a sheave to suspend a vertically-movable member and which is actuated by means of rotation of a sheave to vertically move the vertically-movable member.

Background Art

A wire rope; that is, a steel rope, has hitherto been used as a main cable for suspending an elevator car. In the event that an elevator car accidentally stops for reasons of a power failure or the like, a rescue operation is performed for rescuing passengers confined in the car after determination of a location in a shaft where the car has accidentally stopped.
In preparation for such a rescue operation for rescuing passengers, indices corresponding to car positions in the shaft are marked on the main cable in advance. The position of an accidentally-stopped car is specified by way of an index assigned to the main cable when accidental stoppage of an elevator system has arisen. For instance, a car is located in a position between the fifth and sixth floors, and then passengers are rescued.
In order to enable such an operation for rescuing passengers, after installation of an elevator system the foregoing indices are marked, with appropriate paint, on the main cable consisting of a wire rope. When the elevator system has been used for a long period of time, stains from a rope oil or peeling of paint stemming from wear of the main cable renders identification of the indices difficult. This hinders an operation for rescuing passengers in the event of accidental stoppage of an elevator car.
Consequently, the present invention aims at obtaining a synthetic fiber rope for use with an elevator, in which indices attached to a main cable can be readily identified even after the main cable has been installed.
US Patent US 5,566,786 discloses a cable as suspension means for lifts. A synthetic fiber cable is connected with an elevator car or load-receiving means, with a sheathing, surrounding an outermost cable strand layer, consisting of synthetic material, preferably polyurethane, with the cable strands being twisted or laid up of individual aramide fibers, wherein each individual strand is treated with an impregnating medium for the protection of the fibers and a friction-reducing intermediate sheathing is interposed between the outer most strand layer and the inner strand layer, and in order to obtain an almost circularly shaped strand layer and increase the degree of filling of the strands, any gaps therein are augmented by filler strands.

Summary of the Invention

According to the present invention, there is provided a synthetic fiber rope for use with an elevator, comprising: rope cores; a plurality of strands provided along an outer circumference of the rope cores, each strand being made by means of twisting a plurality of flexible synthetic fibers; and an outer sheath layer which is made of flexible synthetic resin, is formed along an outer circumference of the strands, and has adjacent segments in the longitudinal direction of the fiber rope of predetermined lengths in different colors.
On the basis of a relationship between the colored segments and a sheave around which the main cable is wound, the position of a car in a shaft is assigned to one of the colored segments in the outer sheath layer beforehand.
This realizes a function equal to that of the indices marked on the synthetic fiber rope.
Since the outer sheath layer is made of synthetic resin, the layer can be readily colored during a manufacturing process. Even after an elevator system has been used for a long period of time, there can be prevented difficulty in identifying indices, which would otherwise be caused by wear of the outer sheath layer.
Consequently, there can be appropriately addressed an operation for rescuing passengers in an accidentally-stopped elevator car, thereby speeding the rescue operation.
The outer sheath layer may be made in a color different from that of the strands, thereby facilitating and enabling appropriate determination of the wear state of the outer sheath layer. Because of this, the efficiency of maintenance and inspection of the main cable of the elevator system can be improved.
Moreover, a layer of paint differing in color from the outer sheath layer may be formed on the surfaces of the strands.
Further, a coating layer differing in color from the outer sheath layer may be formed on the surfaces of the strands.
Further, the layer of paint may be embodied as a layer of fluorescent paint.

Brief Descriptions of Drawings

Fig. 1 is a transverse cross-sectional view of a preferable synthetic fiber rope for use with an elevator according to an embodiment; and
Fig. 2 is a perspective view of the synthetic fiber rope shown in FIG. 1.

Embodiments

An embodiment of the present invention will be described by reference to the accompanying drawings. As shown in Figs. 1 and 2, reference numeral 1 designates rope cores provided in the center of a transverse cross section of a synthetic fiber rope. Each of the rope cores is made from a plurality of strands, each strand being made by braiding a plurality of synthetic fibers.
Reference numeral 2 designates a plurality of strands provided along an outer circumference of the rope cores 1, and each of the strands 2 is made by braiding a plurality of flexible synthetic fibers.
Reference numeral 3 designates an outer sheath layer which is made of flexible synthetic resin so as to cover the outer circumference of the strands 2. Reference numeral 4 designates a first segment in the outer sheath layer 3 formed to a predetermined length; 5 designates a second segment formed adjacent to the first segment 4 and painted in a different color from that of the first segment 4; 6 designates a third segment formed adjacent to the second segment 5 and painted in a different color from that of the second segment 5; and 7 designates a fourth segment formed adjacent to the third segment 6 and painted in a different color from that of the third segment 6.
Segments of predetermined lengths which differ in colors from these of other adjacent segments are formed even in other longitudinal locations in the outer sheath layer 3.
The outer sheath layer 3 is formed in a color different from that of the strands 2.
In relation to the synthetic fiber rope for use with an elevator having the foregoing construction, the strands 2 are made of synthetic fibers, and the outer sheath layer 3 is made of flexible synthetic resin. During a manufacturing process, the strands 2 and the outer sheath layer 3 can be readily painted in appropriate colors. On the basis of a relationship between the colored segments and a sheave (not shown) around which the main cable is wound, the position of a car (not shown) in a shaft (not shown) is assigned to one of the colored segments in the outer sheath layer beforehand. This realizes a function equal to that of the indices marked on the synthetic fiber rope.
This structure prevents occurrence of difficulty in identifying indices, which would otherwise be caused by stains when an elevator has been used for a long period of time or a like reason. Consequently, there can be appropriately addressed an operation for rescuing passengers in an accidentally-stopped elevator car, thereby speeding the rescue operation.
Further, the colored segments enable easy determination of the extent of elongation of a synthetic fiber rope due to aging. Thus, the efficiency of maintenance and inspection of the main cable of the elevator system can be improved.
Since the outer sheath layer 3 is formed in a color different from that of the strands 2, a wear state of the outer sheath 3 can be readily and appropriately determined. For this reason, the efficiency of maintenance and inspection of the main cable of the elevator system can be improved.
A coating layer is formed on the surface of each of the strands 2 by means of impregnation of paint. When the outer sheath layer 3 has become worn and has disappeared, the paint of the strands 2 is transferred to the sheave (not shown) around which the synthetic fiber rope is wound. Such a structure enables appropriate determination of wear of the outer sheath layer 3 at the time of periodic inspection of an elevator system, by means of merely observing whether or not the paint of the strands 2 has been transferred to the sheave, without involvement of visual inspection of the entire synthetic fiber rope so as to determine whether or not the strands 2 become exposed in any location of the rope. Thus, maintenance and inspection of the elevator system can be improved. Further, the coating layer to be formed on the surface of the strands 2 is preferably a layer of fluorescent paint. If a layer of fluorescent paint is formed on the surfaces of strands, the paint is easily acknowledged by an inspection worker by means of a fluorescent characteristic. If the paint of the coating layer has been transferred onto a sheave, the paint can be readily detected. Moreover, the fluorescent paint that has been transferred onto the sheave is less prone to disappear. Even if a slight delay has arisen in the time of routine inspection, the paint can be detected readily.

Industrial Applicability

As has been described, a synthetic fiber rope for use with an elevator comprises a plurality of strands provided along an outer circumference of a main cable constituted of the synthetic fiber rope, and an outer sheath layer provided so as to cover each of the strands, wherein adjacent segments of predetermined lengths are formed in different colors in the outer sheath layer. On the basis of a relationship between the colored segments and a sheave around which the main cable is wound, the position of a car in a shaft is assigned to one of the colored segments in the outer sheath layer beforehand. This realizes a function equal to that of the indices marked on the synthetic fiber rope.
This structure prevents difficulty in identifying indices, which would otherwise be caused by stains when an elevator has been used for a long period of time or a like reason. Consequently, there can be appropriately addressed an operation for rescuing passengers in an accidentally-stopped elevator car, thereby speeding the rescue operation. The rope is useful as a synthetic fiber rope for use with an elevator which is wound around a sheave and suspends a vertically-movable member and is suitable for actuation by means of rotation of the sheave, to thereby vertically move the vertically-movable member.
In relation to the synthetic fiber rope for use with an elevator, the outer sheath layer may be made in a color different from that of the strands, thereby facilitating and enabling appropriate determination of the wear state of the outer sheath layer. For this reason, the rope is useful as a synthetic fiber rope for use with an elevator which is wound around a sheave and suspends a vertically-movable member and is suitable for actuation by means of rotation of the sheave, to thereby vertically move the vertically-movable member.

Claims

A synthetic fiber rope for use with an elevator, comprising:
rope cores (1);

a plurality of strands (2) provided along an outer circumference of the rope cores (1), each strand (2) being made by means of twisting a plurality of flexible synthetic fibers; and

an outer sheath layer (3) which is made of flexible synthetic resin and is formed along an outer circumference of the strands (2), characterised in that the outer sheath layer (3) has adjacent segments (4, 5, 6, 7) in the longitudinal direction of the fiber rope of predetermined lengths in different colors.
The synthetic fiber rope according to claim 1, wherein the outer sheath layer (3) is made in a color different from that of the strands (2).
The synthetic fiber rope according to claim 1, wherein a coating layer differing in color from the outer sheath layer (3) is formed on the surfaces of the strands (2).