HK1202513B - A rope of a lifting device, a rope arrangement, an elevator and a condition monitoring method for the rope of a lifting device - Google Patents

Description

Rope for a hoisting device, rope arrangement, elevator and method for monitoring the condition of a rope for a hoisting device

Technical Field

The object of the invention is a rope for a hoisting means as defined in the preamble of claim 1, a rope arrangement as defined in the preamble of claim 11, an elevator as defined in the preamble of claim 12, and a method for condition monitoring of a rope for a hoisting means as defined in the preamble of claim 16.

Background

The elevator car of an elevator is most commonly moved by means of hoisting roping comprising one or more ropes. In order to ensure safety and usability the hoisting roping must be kept in good condition. The hoisting roping is most commonly fixed at its ends to the building and/or to the elevator car and to the counterweight, depending on the suspension ratio and also on the type of roping. With respect to the operation of the elevator, the hoisting roping moves with its ropes as the elevator car moves. The speed of movement of the elevator car and the hoisting ropes is most commonly controlled by means of a traction sheave, and the hoisting ropes are also guided to pass a desired route by means of a diverting pulley. Wear is caused in the hoisting ropes over time, inter alia due to fatigue caused by their guidance and by traction sheave contact and by repeated bending and tensile stresses.

The ropes of the suspension roping of an elevator, including the overspeed governor rope of an elevator, are usually made of metal. Also known in the prior art are elevators in which hoisting roping is used, said hoisting roping comprising ropes having a load-bearing composite part. Such solutions are provided, for example, in publication number WO 20090299. The overspeed governor rope of an elevator is a spiral rope of circular cross-sectional shape, the force-transmitting part of which rope is of a metallic material. A problem in the solutions according to the prior art is that the technical force characteristics relating to its mass cause the mass of the rope to increase more. When an acceleration or deceleration occurs in the elevator car, a corresponding speed change must also occur in the overspeed governor rope. The amount of energy consumed for this depends on the mass of the rope. Yet another problem is creep of the metal rope.

It is known in the prior art that the condition of prior-art ropes of elevators can be evaluated visually. One problem, among others, is the need to individually assess the condition of all the ropes of the elevator. The problem is also caused by the fact that: it is difficult to visually perceive the condition of the coated rope of the elevator.

Efforts have been made to solve the problem of condition monitoring in connection with elevator ropes of composite material construction according to prior art by means of a method in which one load-bearing part of the rope is arranged to be more sensitive to damage in relation to the number of bends than the other load-bearing parts, in which method the condition of the load-bearing part most sensitive to said damage is monitored.

However, there are problems related to the reliability of the method and it is not possible to obtain quantitative data related to the wear of the elevator ropes by means of the method.

Disclosure of Invention

The object of the present invention is in particular to eliminate the drawbacks of the prior art solutions described above. The object of the invention is to improve the condition monitoring of the ropes of the composite material structure of hoisting devices, more particularly passenger elevators and/or freight elevators.

The object of the invention is in particular to achieve one or more of the following advantages:

-realizing the safety rope of an elevator and an elevator with safety roping.

An efficient and reliable condition monitoring method is achieved, by means of which also quantitative data concerning the condition of the rope can be achieved.

An elevator rope, a condition monitoring method for an elevator rope and an elevator are achieved that are advantageous from the point of view of condition monitoring.

A rope of an elevator is achieved, which rope is light in weight with respect to its own weight and has a high tensile strength and tensile rigidity.

A rope of an elevator is achieved, which rope has a high thermal conductivity in combination with a high operating temperature.

A rope for an elevator is achieved which has a simple, belt-like structure and is simple to manufacture.

A rope is achieved which comprises a straight or a number of substantially parallel straight load-bearing parts, in which case the bending properties are advantageous.

An elevator with light-weight roping is achieved.

An elevator and the rope of an elevator are achieved in which the moving and accelerating masses and the shaft load are smaller than before.

An elevator and a rope are achieved in which there are no discontinuities or intermittencies of the rope, whereby the rope of the elevator is quiet and advantageous in terms of vibrations.

A rope is achieved which has less internal wear.

A rope is achieved which has a good fatigue resistance.

An energy efficient elevator is achieved.

An elevator with effective spacing is achieved, the overspeed governor rope of which is light in weight and has a small bending radius.

An elevator is achieved, the mass of the part of the elevator moving with the car being smaller than before.

An elevator is achieved, the creep of the overspeed governor rope of which is small.

An elevator is achieved, the braking of the overspeed governor rope of which can be performed simply and lightly without damaging the fibers of the rope by a large surface area.

An elevator is achieved, the lateral movement of the overspeed governor rope of which is small.

The invention is based on the idea that: in an elevator system, the elevator car, the counterweight, or both, can be safely supported and/or moved by means of a rope of composite material construction according to the invention, the condition monitoring of the aforementioned rope can be arranged according to the invention to use sensors of a length of even hundreds of meters. The rope according to the invention is also suitable for use as an overspeed governor rope and as a compensating rope. The rope according to the invention can be suitably used both in elevators provided with a counterweight and in elevators without a counterweight. The rope and/or rope arrangement according to the invention can also be used in connection with other hoisting devices, for example in roping for cranes. The light weight of the rope of composite material structure is useful, especially in acceleration situations, because the energy required for the speed change of the rope depends on its mass. In addition, the light weight makes handling of the rope easier.

The rope of the hoisting device according to the invention can be said to be characterized by what is disclosed in the characterization part of claim 1. The rope arrangement according to the invention can be said to be what is disclosed in the characterizing part of claim 11. The elevator according to the invention can be said to be characterized by what is disclosed in the characterization part of claim 12. The method for monitoring the condition of a rope for a hoisting device according to the invention is said to be characterized by what is disclosed in the characterization part of claim 16. Other embodiments of the invention are characterized by what is disclosed in the other claims. Some embodiments of the invention are also presented in the description part and drawings of the present application. The inventive content of the application can also be defined differently than in the claims presented below. The inventive content may also consist of several separate inventions, especially if the invention is considered in the light of expressions or implicit sub-tasks or from the point of view of advantages or categories of advantages achieved. In that case, some of the attributes contained in the claims below may be superfluous from the point of view of separate inventive concepts. The features of the various embodiments of the invention can be applied within the scope of the basic idea of the invention in combination with other embodiments.

Preferably, the cross-section of the cord is rectangular or conical in shape, the width of the cord being greater than the thickness.

Preferably, the rope comprises a plurality of load-bearing parts in the longitudinal direction of the rope, which parts are distributed in the rope at a distance from each other in the width direction of the rope, which rope is bendable around a central axis in the width direction of the rope, and the rope comprises at least one load-bearing part extending in the thickness direction of the rope to a first distance from a neutral axis in the width direction of the rope, and at least one load-bearing part extending to a second distance from the central axis in the width direction of the rope, which second distance is greater than said first distance.

Preferably, the load-bearing parts of the ropes are substantially of the same material, preferably of identical material.

Preferably, the load-bearing part described above is a fibre-reinforced composite, preferably a glass fibre-reinforced, more preferably an aramid fibre-reinforced, most preferably a carbon fibre-reinforced composite.

Preferably, the load-bearing part mentioned above is a polymer fibre-reinforced material, such as polybenzoxazole fibre-reinforced, or polyethylene fibre-reinforced, such as UHMWPE fibre-reinforced, or nylon fibre-reinforced composite material. All reinforcements are therefore lighter than wire.

Preferably, the proportion by volume of the reinforcement of each load-bearing part described above is at least 50% of the volume of the reinforcing fibres in the load-bearing part. In this way the longitudinal mechanical properties of the load-bearing part are sufficient.

Preferably, the proportion of reinforcement of each of the above-mentioned load-bearing parts is at least 50% of the weight of the reinforcing fibres in said load-bearing part. In this way the longitudinal mechanical properties of the load-bearing part are sufficient.

Preferably, at least 50% of the surface area of the cross-section of each of the above-mentioned load-bearing parts is reinforcing fibres. In this way the longitudinal mechanical properties of the load-bearing part are sufficient.

Preferably, the aforementioned load-bearing part or load-bearing parts together cover 40%, preferably 50% or more, more preferably 60% or more, more preferably 65% or more of the surface area of the cross-section of the rope. In this way, a large part of the cross-sectional area of the rope is load-bearing.

Preferably, the above-mentioned load-bearing part is a fibre-reinforced hybrid composite material, preferably a glass fibre-reinforced and/or aramid fibre-reinforced and/or carbon fibre-reinforced hybrid composite material. In this way, optimum mechanical properties, such as strength properties, stiffness properties, vibration properties and/or thermo-mechanical properties, can always be selected for the rope as desired.

In one embodiment one, preferably two, most preferably each composite part of the load-bearing composite part of the rope comprises one or more optical fibers, most preferably all bundles or rolls of optical fibers, inside it, which are arranged substantially inside and/or near the surface of said load-bearing part, as seen in the thickness direction of the rope. Thus, good measurement accuracy is achieved.

In one embodiment, the condition monitoring method for the rope is based on measurements, in which the optical fiber acts as an optical Fabry-perot type sensor.

In one embodiment, the condition monitoring method for a rope is based on measurements, wherein a single piece of optical fiber is used as the optical fiber, which comprises a bragg grating, i.e. the fiber bragg grating FBG method is applied in the condition monitoring of said rope.

In one embodiment, the condition monitoring method for the rope is based on measurements, wherein sensors operating on the time of flight TOF principle are used as optical fibers.

In one embodiment, a condition monitoring method for a rope is based on measurements, wherein a sensor based on brillouin spectroscopy is used as an optical fiber.

Preferably, the tensile strength and/or modulus of elasticity of at least some, most preferably all, of the load-bearing portions is adapted to be substantially the same.

Preferably, the surface area of the cross-section of at least some, most preferably all, of the load-bearing portions is substantially the same.

Preferably, the load-bearing parts are visible outside the rope, due to the transparency of the matrix bonding the load-bearing parts to each other.

Preferably the ropes and/or rope arrangements of the hoisting means, more particularly of a passenger elevator and/or a freight elevator, comprise a plurality of ropes, which are arranged to move the elevator car, e.g. by means of a traction sheave. Preferably, at least one of the above-mentioned cords is provided with one or more optical fibers, most preferably with a fiber bundle or fiber reel.

Preferably, the width/thickness ratio of the rope is at least 2 or more, preferably at least 4, or even 5 or more, or even 6 or more, or even 7 or more or even 8 or more. In this way, good force transmission is achieved by a small bending radius. This can preferably be achieved by the fibre-reinforced composite material provided in this patent application, which has a very advantageously large width/thickness ratio due to the rigidity of the structure.

Preferably, the width of each of the aforementioned force transmitting portions is greater than the thickness, preferably such that the width/thickness ratio of each of the aforementioned force transmitting portions is at least 1.3 or more, or even 2 or more, or even 3 or more, or even 4, or even 5 or more. In this way, a wide rope can be simply formed and is thin.

Preferably, the plurality mentioned in the cord arrangement comprises a plurality of cords, wherein each cord is bendable around a widthwise central axis of the cord. Each of the above-mentioned cords comprises at least one or more optical fibers, preferably bundles or rolls of fibers, near the surface of the load-bearing part, inside the load-bearing part and/or embedded in a polymer matrix.

Preferably, the optical fibers and/or fiber bundles comprised in the rope or rope arrangement described above are substantially transparent to the LED light or laser light. Thus, the condition of the load-bearing portion can be monitored by monitoring a change in one of its optical properties.

Preferably, the density of the reinforcing fibers of the rope or rope arrangement is less than 3.5 kg/m, and the tensile strength is 2GPa or more. One advantage is that the fibers are lightweight, but they need not be numerous because they are strong.

Preferably, the load-bearing part of the above-mentioned rope or rope arrangement is a complete elongated rod-like member.

Preferably, the load-bearing part of the above-mentioned rope or rope arrangement is substantially parallel to the longitudinal direction of the rope.

Preferably, the structure of the rope or rope arrangement described above is substantially the same over the entire distance of the rope.

Preferably, the aforementioned reinforcing fibers and one or more optical fibers are in the longitudinal direction of the rope.

Preferably, the individual reinforcing fibers and/or one or more optical fibers and/or fiber bundles are homogeneously distributed in the above-mentioned matrix.

Preferably, the aforementioned reinforcing fibers and/or one or more optical fibers and/or bundles of optical fibers are fibers that are continuous in the longitudinal direction of the rope, which fibers preferably extend the entire length of the rope.

Preferably, the aforementioned reinforcing fibers and/or one or more optical fibers and/or bundles of optical fibers are bonded into the complete load-bearing part by the aforementioned polymer matrix, preferably by arranging the optical fibers between or on the surface of the prepreg glue layers or by laminating the reinforcing fibers and the optical fibers in the material of the polymer matrix at the manufacturing stage.

Preferably, the above-mentioned load-bearing part comprises straight reinforcing fibers substantially parallel to the longitudinal direction of the rope and/or one or more optical fibers and/or fiber bundles, which are bound into a complete part by the polymer matrix.

Preferably, substantially all of the reinforcing fibers and/or one or more optical fibers and/or bundles of fibers of the load-bearing part described above are in the longitudinal direction of the rope.

Preferably, the structure of the load-bearing part extends substantially the same over the entire distance of the rope.

Preferably, the polymer matrix is non-elastomeric.

Preferably, the elastic modulus E of the polymer matrix material is above 1.5GPa, most preferably above 2GPa, even more preferably in the range of 2-10GPa, most preferably all in the range of 2.5-4 GPa.

Preferably, the polymer matrix comprises an epoxy, a polyester, a phenolic or a vinyl ester.

Preferably, more than 45% of the surface area of the cross-section of the load-bearing part is the above mentioned reinforcing fibers, preferably such that 45-85% are the above mentioned reinforcing fibers, more preferably such that 60-75% are the above mentioned reinforcing fibers and optical fibers, most preferably such that approximately 59% of the surface area is reinforcing fibers up to 1% are optical fibers, approximately 40% is matrix.

Preferably, the reinforcing fibers and one or more optical fibers and/or fiber bundles together with the matrix form a complete carrier part in which abrasive movements between the fibers or between the fibers and the matrix substantially do not occur.

Preferably, the width of the load-bearing part is greater than the transverse thickness of the rope.

Preferably, the line comprises a plurality of load bearing parts as described above side by side.

Preferably, the load-bearing portion is surrounded by a polymer layer, which is preferably an elastomer, most preferably a high friction elastomer such as polyurethane.

Preferably, the load-bearing part or parts cover a substantial part of the cross-section of the rope.

Preferably, the carrier part comprises the above-mentioned polymer matrix, reinforcing fibers bonded to one another by the polymer matrix, and one or more optical fibers and/or optical fiber bundles, and possibly also a sizing surrounding the fibers, and possibly also additives incorporated into the polymer matrix.

Preferably, the structure of the rope extends substantially the same over the entire distance of the rope, which rope comprises wide and at least substantially flat, preferably completely flat sides for enabling friction-based force transmission via said wide surfaces.

According to the invention, the elevator, more particularly a passenger and/or freight elevator, comprises an elevator car, a traction sheave, and a power source for rotating the traction sheave. It comprises a rope of one of the types described earlier and/or a rope arrangement of one of the types described earlier. The elevator car is arranged to be moved by means of the aforementioned ropes and/or rope arrangements.

Preferably the ropes and/or rope arrangements are arranged to move the elevator car and the counterweight.

Preferably the elevator comprises a rope pulley, preferably near the top end of the path of movement of the elevator car, on which one or more ropes of the suspension roping, when supported, support the elevator car and the counterweight, preferably in 1:1 suspension or in 2:1 suspension.

According to the invention the elevator comprises means for monitoring the condition of the optical fibres and/or bundles of optical fibres of the rope, which means monitor the condition of preferably only one or more of the optical fibres and/or bundles mentioned above from the load-bearing part of the rope.

Preferably, in the method for monitoring the condition of a rope and/or roping comprising a plurality of optical fibers and/or fiber bundles arranged in some, preferably one, more preferably two, most preferably in a number of load bearing parts, and in the method the condition of the load bearing part containing the optical fibers is monitored.

Preferably, in the method, the condition of all bearer portions is not monitored.

Advantageously, the condition of the load-bearing part, but not those comprising the optical fiber, is not monitored at all or at least in the same way as the condition of the part comprising the optical fiber.

Preferably, in the method, the condition of the rope and/or rope arrangement is monitored by monitoring the condition of the portion comprising one or more optical fibres and/or fibre bundles in one of the following ways:

by measuring the change in the transit time of a light pulse that has occurred in the optical fiber,

by detecting changes in the spectrum and/or phase and/or wavelength of the reflected, deflected or scattered light,

by detecting the amount of light passing through the fiber visually or by means of a photodiode,

by comparing the values measured from different fibers and/or fiber bundles with each other and by observing the deviation between the measured values rather than the absolute values.

In one embodiment, in the method, the condition of the rope and/or roping is monitored by monitoring the condition of one or more optical fibers and/or fiber bundles and if it is detected that the part comprising the optical fibers has broken or its condition has fallen below a certain predetermined level, the need to replace or overhaul one or more ropes is judged and a rope replacement work or a rope repair work is started.

In one embodiment, in the method, the condition of the ropes and/or roping is monitored by monitoring the condition of a number of optical fibres and/or bundles of optical fibres, and if a difference between the monitored fibre conditions is detected, the need to replace or overhaul one or more ropes is judged, and a rope replacement or rope repair operation is started.

Preferably, by the method the condition of the rope and/or roping is monitored by monitoring changes in the characteristics in one or more parts of one or more optical fibres and/or fibre bundles, for example in the propagation of a light pulse, and/or on the basis of changes occurring in the spectrum. In one embodiment, the tension created by the weight of the elevator car/counterweight is transferred from the elevator car/counterweight at least to the traction sheave along at least one of the above-mentioned parts.

In one embodiment, the optical fibers of the rope also function as a long vibration sensor. In the vibration measuring apparatus, a single-mode optical fiber or a multimode optical fiber is used as a sensor and a semiconductor laser is used as a light source. The detection of the vibration is based on the variation of the speckle profile formed by the bright and dark spots occurring at the second end of the optical fiber (in the far end field).

Preferably, the optical cable used for measurement purposes comprises a number of optical fibers required for the measurement and, in addition to these, optical fibers for data transmission.

Drawings

The present invention will now be described primarily in conjunction with the preferred embodiments thereof, and with reference to the accompanying drawings, in which:

1a-1j schematically show one embodiment of each rope according to the invention;

fig. 2 schematically shows an enlarged detail of a cross-section of a rope according to the invention;

fig. 3 presents an embodiment of the elevator according to the invention;

fig. 4 schematically shows a measuring system according to one embodiment of the condition monitoring method for a rope according to the invention.

Detailed Description

Fig. 1a-1j schematically show preferred cross sections of hoisting ropes according to different embodiments of the invention as seen in their longitudinal direction. The rope 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 shown in fig. 1a-1j is belt-shaped, i.e. the rope has a measured thickness t in a first direction at right angles to the longitudinal direction of the rope and a measured width w in a second direction, which is the longitudinal direction of the rope and at right angles to the aforementioned first direction, which width w is substantially larger than the thickness t. The width of the cord is thus substantially greater than said thickness. In addition, the rope preferably, but not necessarily, has at least one, preferably two, wide and substantially flat surfaces, in which case the wide surfaces can effectively be used as force transmission surfaces with friction or positive contact (positive contact), since such wide contact surfaces are achieved. The broad surface need not be completely flat, but instead there may be a groove in it or a protrusion on it, or it may have a curved shape. The structure of the rope continues preferably substantially the same throughout the distance of the rope. If so desired, the cross-section may also be arranged to change intermittently, for example as toothing.

The rope 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 comprises a load-bearing part 11, 21, 31, 41, 51, 61, 71, 81, 91, 101 in a polymer matrix, which is a carbon-fibre-reinforced, aramid-fibre-reinforced and/or glass-fibre-reinforced composite material comprising carbon fibres, aramid fibres and/or glass fibres, most preferably carbon fibres, and one or more optical fibres, more preferably one or more fibre bundles. The reinforcing fibers and optical fibers are longitudinal to the rope, for which reason the rope retains its structure when bent. The individual fibres are thus essentially aligned in the longitudinal direction of the rope, in which case the fibres are aligned with said forces when the rope is pulled. The optical fibre and/or fibre bundle may be one continuous fibre or bundle laminated within the composite structure or near the surface of the composite structure such that the fibre enters the structure interior at the first end of the rope, folds back at the other end of the rope and exits the structure again at the first end of the rope. The fibers and/or fiber bundles may be coiled, i.e. the fiber barrel (fiber can) has one or more bends on the inside or surface of the structure so that however only one fiber and/or fiber bundle is used for the measurement, which may enter and exit from the same or different end of the rope. Also a number of parallel fibres or bundles can be used for the measurement, laminated in a corresponding manner within the composite structure or near its surface.

The rope 10 shown in fig. 1a comprises a load-bearing composite portion 11 of substantially rectangular cross-sectional shape, which is surrounded by a polymer jacket (envelope) 1. In the cross-section of the composite part 11 of the figure, optical fibres and/or fibre bundles 2, which may be coiled identical fibres or different parallel fibres, are seen in three places. Thus, for example, a good measurement accuracy for strain is achieved by the system. Alternatively, the cord may be formed without the polymer jacket 1.

The cord 20 shown in fig. 1b comprises a load-bearing composite portion 21 having a substantially rectangular cross-sectional shape, which is surrounded by a polymer jacket 1. A wedge surface is formed on the surface of the cord 20 by a plurality of wedge-shaped protrusions 22, which are preferably integral parts of the polymer jacket 1. In this figure, an optical fibre and/or fibre bundle 2, preferably comprising at least one sensor fibre, preferably also a reference fibre, is glued essentially on the surface of the composite part in the vicinity of the three wedge-shaped protrusions. The reference fibre may also be mounted inside the envelope so that the strain induced by the structure to be measured is not exerted on it.

The cord 30 shown in fig. 1c comprises two side by side load-bearing composite portions 31, rectangular in their cross-sectional shape, surrounded by a polymer jacket 1. The polymer jacket 1 comprises a protrusion 32 for guiding the cord 30 in the centre of the area between the portions 31 at the midpoint of the broad sides of the cord. There may be more than two composite portions 51 in the rope 50 side by side in this way, as shown in fig. 1 e. In fig. 1c and 1e, an optical fiber and/or fiber bundle 2, preferably comprising a sensor fiber and a reference fiber, are both provided in composite parts and embedded in a polymer jacket between the composite parts. The reference fiber may also be mounted inside the envelope so that the strain caused by the structure to be measured is not exerted on it. The polymeric jacket may also be free of tabs or the tabs may be located at different locations of the polymeric jacket.

The cord 40 shown in fig. 1d comprises a load-bearing composite part 41 having a rectangular cross-sectional shape, which composite part 41 is surrounded by a polymer jacket 1. The edge of the cord comprises a protrusion 42, which is preferably part of the polymer jacket 1. An advantage of the projections 42 is that they protect the edges of the composite material part, for example against fraying. Optical fibers and/or fiber optic bundles 2 are embedded in the protrusion 42 adjacent the surface of the composite portion for monitoring the condition of the composite portion and/or for data transfer. The optical fibers and/or fiber bundles may also be glued to the surface of the polymer jacket.

The rope 60 shown in fig. 1f comprises a plurality of load-bearing composite parts 61 of circular cross-sectional shape, which may also be braided and surrounded by a polymer jacket 1, and in a part of the composite parts 61 optical fibers and/or fiber bundles 2 are arranged, which preferably comprise at least one present sensor fiber.

The rectangular cross-sectional shaped rope 70 shown in fig. 1g comprises a plurality of load-bearing composite portions 71 which are rectangular in their cross-sectional shape and are placed side by side in the width direction of the belt and surrounded by a polymer jacket 1. Near the surface of the composite part 71, and/or between them, is an optical fiber and/or fiber bundle 2 in a polymer jacket in a laminate, which preferably comprises at least one sensor fiber and preferably also a reference fiber.

The cord 80 shown in fig. 1h comprises two load-bearing composite portions 81 side by side, which are rectangular in cross-sectional shape and surrounded by a polymer jacket 1. The polymer jacket 1 comprises grooves 82 for making the cord flexible at the location of the areas between the portions 81 in the broad sides of the cord 80, in which case the cord shapes itself sufficiently, in particular a surface preventing bending. The rope may alternatively be guided by means of grooves. Thus, there may be more than two composite portions 101 in the rope 100 side by side in such a way as shown in fig. 1 j. In the composite part 81, 101 and near the surface of the composite part 81, 101 or between the composite parts are optical fibers and/or fiber bundles 2 embedded in a polymer jacket 1, which preferably comprises at least one sensor fiber and a reference fiber. The reference fiber may also run, for example, within the groove so that the strain caused by the structure to be measured is not exerted on it. The polymer jacket may also be free of grooves, which may be asymmetrically positioned with respect to the axis of symmetry of the cord, or it may be disposed in a different location than that shown in the figure.

The rope 90 shown in fig. 1i comprises a load-bearing composite part 91, the cross-sectional shape of which is rectangular, on both sides of which are wires 92, both the composite part 91 and the wires 92 being surrounded by a polymer jacket 1. The wire 92 may be a rope or strand or braid and it is preferably formed of a shear resistant material such as metal or aramid fiber. The wire may also comprise an optical fiber or fiber bundle 2 associated with the rope or strand or braid, which preferably comprises at least one sensor fiber and a reference fiber. Instead of a wire, only one optical fiber and/or fiber bundle 2 may be at the rope side. Preferably the wires are at the same distance from the surface of the rope as the composite part 91. The metallic protective layer may be of another type, such as a metallic lath or a metallic mesh along the composite portion.

Fig. 2 shows a preferred structure for carrying the composite material parts 11, 21, 31, 41, 51, 61, 71, 81, 91, 101. Part of the cross-section of the surface structure of the load-bearing composite part (as seen in the longitudinal direction of the rope), according to which the reinforcing fibers of the load-bearing part provided elsewhere in this application are preferably in a polymer matrix, is provided within the circle of the figure. The figure shows how the reinforcing fibres F are substantially evenly distributed in the polymer matrix M, surrounding the fibres and fixed to them. Optical fibers and/or fiber bundles O, which function as actual sensor fibers, are arranged in a plurality of reinforcing fibers F. The reinforcing fibers may also consist of unidirectional reinforcing layers, preferably prepreg layers, laminated to each other. The polymer matrix M fills the area between the reinforcing fibers F and the optical fibers O and bonds substantially all of the fibers F, O within the matrix to each other as an integral solid mass. In this case, relative abrasive movement between the fibers F, O and the matrix M is substantially prevented. There is a chemical bond between preferably all the fibers F, O and the matrix M, one advantage of which is the homogeneity of the structure. In order to strengthen the chemical bond, there may be a sizing (not shown) between the fibers F, O and the polymer matrix M, but this is not essential. The polymer matrix M is of the kind described elsewhere in this application and may thus comprise additives as a supplement to the base polymer for adjusting the properties of the matrix. The polymer matrix M is preferably a hard thermoset plastic, such as an epoxy resin or a polyester resin. The fact that the fibres F, O are in the polymer matrix in the load-bearing part means that in the present invention the individual fibres F, O are bonded to each other by means of the polymer matrix M, for example by embedding them in the material of said polymer matrix at the manufacturing stage. The optical fibres and/or bundles of optical fibres may also be arranged between the prepreg unidirectional layers or glued onto the surface in the direction of the layers at the manufacturing stage. In this case, the interstices of the individual fibers F, O, which are bonded to each other by the polymer matrix, comprise the polymer of said matrix. Thus in the present invention, a large number of reinforcing fibers F and optical fibers O, preferably bonded to each other in the longitudinal direction of the cord, are distributed in said polymer matrix.

The reinforcing fibers are preferably substantially uniformly, i.e. homogeneously, distributed in the polymer matrix so that the load-bearing part is as homogeneous as possible when seen in the cross-sectional direction of the rope. In other words, the fibre content in the cross section of the composite material part thus does not vary much. The reinforcing fibers and the optical fibers and the matrix form a complete load-bearing part inside which no relative abrasive movements occur when the rope is bent. The individual fibers of the load-bearing part are mainly surrounded by the polymer matrix, but the contact between the fiber barrels takes place in places, because it is difficult to control the position of the fibers relative to each other while injecting the polymer matrix, on the other hand, a very perfect elimination of any contact between the fibers is not entirely necessary from the functional point of view of the invention. However, if it is desired to reduce any occurrence of them, the individual fibers may be pre-coated so that the polymer size already surrounds the individual fibers before they are bonded to each other. In the present invention, the individual fibers of the load-bearing part may comprise a polymer matrix material surrounding them such that the polymer matrix immediately abuts the fibers, but instead of a thin sizing of the fibers, a primer (primer) arranged on the surface of the fibers at the manufacturing stage to improve chemical adhesion to the matrix material may be in between. The optical fiber may be protected with polyimide.

The individual reinforcing fibers are evenly distributed in the load-bearing part such that the interstices of the individual reinforcing fibers comprise the polymer of the matrix. Preferably, most of the interstices of the individual reinforcing fibers in the load-bearing part are filled with matrix polymer. Most preferably, substantially all of the interstices of the individual reinforcing fibers in the load-bearing part are filled with the polymer of the matrix. The substrate of the load-bearing part is most preferably hard in its material properties. The stiff matrix helps to support the reinforcing fibers, especially when the rope is bent. When bending, tension is exerted on the fibres of the outer surface of the rope and pressure is exerted on the fibres of the inner surface in their longitudinal direction. Under the influence of pressure, the fibers attempt to bend and deform. When a hard material is chosen as the polymer matrix, the wrinkling of the fibre drum is prevented, because the hard material is able to support the fibres and thus prevent them from wrinkling and equalize the stresses inside the rope. Especially in order to reduce the bending radius of the rope, it is therefore advantageous that the matrix material is a polymer which is hard, something which is preferably not an elastomer (e.g. rubber) or other substance which exhibits elasticity or yield. Most preferred materials are epoxy, polyester, phenolics and vinyl esters.

In the method according to the invention for monitoring the condition of a rope and/or roping, said rope 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 and/or roping R comprises a number of load-bearing parts, inside and/or near its surface, and/or in a polymer matrix surrounding it, one or more optical fibers and/or fiber bundles are integrated as sensor fibers and/or as reference fibers, in which method the condition of the sensor fibers is monitored, for example by measuring the transit time of light pulses in the sensor fibers. The ropes and/or roping are according to what is provided elsewhere in the patent application, for example in fig. 1a-1 j. In the method the condition of all or part of the ropes and/or roping is monitored by monitoring the condition of the sensor fibre, and if it is detected that a part of the sensor fibre has been damaged or its condition has decreased below a certain predetermined level, the need for replacement or overhaul of one or more ropes is judged and a rope replacement work or rope repair work is started. In the method, the transit times of the light pulses may also be measured in different ropes, the transit times of the light pulses may be compared with each other, and when the difference between the transit times of the light pulses increases to the above-mentioned predetermined level, the need to replace or overhaul one or more ropes is judged and a rope replacement work or a rope maintenance work is started.

Fig. 3 presents an embodiment of the elevator according to the invention, in which the hoisting roping of the elevator is according to what is presented elsewhere in this patent application, e.g. as defined in the description of any of fig. 1a-1 j. The roping 10, 20, 30, 40, 50, 60, 70, 80, 90100, R is fixed at its first end to the elevator car 4 and at its second end to the counterweight 5. The roping is moved via a traction sheave 3 supported on the building, to which a power source, such as an electric motor (not shown), which rotates the traction sheave, is connected. The rope is preferably of any of the types shown in fig. 1a-1 j. The elevator is preferably a passenger transport elevator and/or a freight transport elevator, which is installed to run in an elevator shaft S in the building.

Fig. 4 presents an embodiment of the condition monitoring method for the ropes or ropings of an elevator according to the invention, wherein the elevator preferably comprises a separate condition monitoring arrangement operating on the transmission time TOF principle, which condition monitoring arrangement comprises a condition monitoring device 7 connected to the sensor fiber 2a and the reference fiber 2b of the rope, which device comprises equipment, such as a computer, including a laser transmitter, a receiver, a timing discriminator, a circuit measuring the time interval, a programmable logic circuit and a processor 6. The condition monitoring arrangement comprises one or more sensors S1, S_N/3Each sensor comprising, for example, a reflector R1, R2, R3, R_N-2，R_N-1，R_NWhere N is the number of reflectors, and a processor 6 which issues an alarm related to excessive wear of the rope when they detect a change in the transit time of the light pulses, for example in the sensor fiber 2 a. Common mode errors, for example caused by temperature changes, can be eliminated by the reference fiber 2 b. A number of sensor fibers 2a and reference fibers 2b may be connected in series with each other, the reflectors R1, R2, R3, R_N-2，R_N-1，R_NIs located in the fiber connector. Based on the transit time of the light pulse, preferably by comparison with a predetermined limit value by means of a processor, the condition monitoring device is arranged to infer the condition of the carrier part in the region between the reflectors. The condition monitoring device may be arranged to initiate an alarm if the transit time of the light pulse does not fall within a range of expected values or is completely different from the measured values of the transit time of the light pulse for the other rope being measured. The transit time of the light pulse changes when a characteristic, such as strain or displacement, which depends on the condition of the load-bearing part of the rope changes. For example, due to the interruption, the transmission time of the light pulse changes, from which it can be inferred that the carrying part is in a bad condition.

The property to be observed may also be, for example, a change in the amount of light passing through the rope. In this case, the light enters the optical fiber from one end by means of a laser transmitter or by means of an LED transmitter, the light being estimated visually by the passage of the rope or by a photodiode at the other end of the fiber. When the amount of light traveling through the rope is significantly reduced, the condition of the rope is estimated to have deteriorated.

In one embodiment of the condition monitoring method for a rope, the optical fibre functions as an optical sensor of the Fabry-perot type. The Fabry-perot interferometer FPI comprises two reflecting surfaces at the ends of the fiber, or two parallel dichroic mirrors with very good reflectivity. When it strikes the mirror, a portion of the light passes through and a portion reflects back. After this mirror, the passing light travels, for example, through air, after which it is reflected back from the second mirror. Some light has traveled a longer distance in a different material, which has caused some change in the characteristics of the light. The strain causes a change, for example, in the light phase. The light of which the characteristic is changed interferes with the original light, and thereafter the change is analyzed. After the light has combined, they end up in the receiver and signal processing means. By this method the strain of the fibres, and thus the condition of the rope, is estimated.

In one embodiment of the condition monitoring method for a rope, an optical fiber is used, which fiber comprises a Bragg grating, so-called fiber Bragg grating, the FBG method being applied in the condition monitoring of a rope. A periodic grating structure is fabricated in a single mode fiber for FBG sensors, which reflects a certain wavelength of light back, corresponding to the grating. When light is conducted into the fibers, light of a wavelength corresponding to the grating is reflected back. When strain is applied to the lattice structure, the refractive index of the fibers changes. The change in refractive index affects the wavelength of the light reflected back. By monitoring the change in wavelength, a change in the strain exerted on the grating can be determined, and thus the condition of the rope. There may be tens or hundreds of grids on the same fiber side.

In one embodiment of a condition monitoring method for a wireline, a distributed sensor fiber based on brillouin spectral measurements is used. A common single mode fiber or a multimode fiber may be used as the sensor. The optical fiber functions as a distributed sensor, which can function as a sensor several hundred meters long, measuring over its length and corresponding to sensors in the form of thousands of dots, if necessary. The backscattering of light occurs continuously as the light propagates through the fiber. This can be exploited by monitoring the intensity (strength) of certain backscattered wavelengths. Brillouin scattering occurs in a heterogeneous spot generated in the fiber at the manufacturing stage. By observing the wavelengths of the primary and scattered light signals, the strain of the fibers, and thus the condition of the rope, is determined.

The temperature effect on the strain measurement can be eliminated, in particular, by using as an aid a reference fiber which is mounted such that the strain caused by the structure to be measured is not exerted on it.

It is obvious to a person skilled in the art that while developing this technology, the basic idea of the invention may be implemented in many different ways. The invention and its embodiments are thus not limited to the examples described above, but they may instead vary within the scope of the claims.

Claims (32)

1. A rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) for a hoisting device,

-the width of the rope is larger than the thickness in the transverse direction of the rope,

-the rope comprises a load-bearing part (11, 21, 31, 41, 51, 61, 71, 81, 91) in the longitudinal direction of the rope, which load-bearing part comprises a carbon-fibre-reinforced, aramid-fibre-reinforced and/or glass-fibre-reinforced composite material in a polymer matrix, and

-the rope comprises one or more optical fibres and/or bundles (2) of optical fibres in combination with the load-bearing part (11, 21, 31, 41, 51, 61, 71, 81, 91), characterized in that,

-the above-mentioned optical fibers and/or fiber bundles (2) comprising several optical fibers, -being laminated inside the carrier part (11, 21, 31, 41, 51, 61, 71, 81, 91) and/or-the above-mentioned optical fibers and/or fiber bundles (2) being glued onto the surface of the carrier part (11, 21, 31, 41, 51, 61, 71, 81, 91) and/or-the above-mentioned optical fibers and/or fiber bundles (2) being embedded or glued into a polymer jacket surrounding the carrier part (11, 21, 31, 41, 51, 61, 71, 81, 91), -the above-mentioned optical fibers and/or fiber bundles (2) comprising a sensor fiber (2a) and a reference fiber (2b) through which common mode errors caused by temperature changes are eliminated.

2. A rope according to claim 1, characterized in that the hoisting means is a passenger and/or freight elevator.

3. A rope according to claim 1, charac teri z ed in that said rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) extends equally over the entire length of said rope, and in that said carbon fibre-reinforced, aramid fibre-reinforced and/or glass fibre-reinforced load-bearing part (11, 21, 31, 41, 51, 61, 71, 81, 91) comprises prepreg reinforcing layers laminated together, said optical fibres and/or bundles of optical fibres (2) being laminated between and/or on the surface of said reinforcing layers.

4. A rope according to claim 1, charac teri z ed in that said carbon fiber-reinforced, aramid fiber-reinforced and/or glass fiber-reinforced load-bearing part (11, 21, 31, 41, 51, 61, 71, 81, 91) comprises unidirectional reinforcing fibers laminated into said polymer matrix, and that said optical fibers and/or bundles (2) of optical fibers are arranged to be mixed into said reinforcing layer.

5. A rope according to claim 1, charac teri z ed in that said load-bearing part (11, 21, 31, 41, 51, 61, 71, 81, 91) comprises said optical fibers and/or fiber bundles (2), which are the length of said load-bearing part, or longer, and which are arranged to run continuously at least once from its first end to its second end in the direction of said load-bearing part.

6. A rope according to claim 5, charac teri z ed in that the optical fibres and/or bundles are arranged to run in succession more than once from its first end to its second end in the direction of said load-bearing part.

7. A rope according to claim 5, charac teri z ed in that the optical fibres and/or bundles are arranged to run successively more than twice from its first end to its second end in the direction of said load-bearing part.

8. Rope according to any one of the preceding claims 1-7, characterized in that the input and reception of light pulses of the aforementioned optical fibers and/or bundles (2) is at the same end of the aforementioned rope or in that the input and reception of light pulses of the aforementioned optical fibers and/or bundles (2) is at the opposite end of the aforementioned rope.

9. A rope according to any one of the preceding claims 8, charac teri z ed in that a single-mode or multimode optical fibre is used as the sensor fibre of the aforementioned optical fibre or fibre bundle (2), the input of said light pulses taking place by means of a laser transmitter, or by means of a light-emitting diode light source.

10. A rope according to any one of the preceding claims 9, charac teri z ed in that the laser transmitters are semiconductor lasers.

11. Rope according to any one of the preceding claims 1-7, 9, 10, charac teri z ed in that the aforementioned optical fibres and/or fibre bundles (2) comprise sensor fibres of the Fabry-perot type.

12. A rope according to any one of the preceding claims 1-7, 9, 10, charac teri z ed in that said optical fibers and/or bundles (2) comprise sensor fibers comprising a bragg grating structure.

13. A rope according to any one of the preceding claims 1-7, 9, 10, charac teri z ed in that said optical fibers and/or fiber bundles (2) comprise sensor fibers, which function as Brilloun distributed fiber sensors.

14. Rope according to any one of the preceding claims 1-7, 9, 10, charac teri z ed in that the aforementioned optical fibres and/or fibre bundles (2) comprise sensor fibres in which the transit time of a light pulse is measured.

15. A rope arrangement (R) of a hoisting device, which rope arrangement comprises a plurality of ropes (10, 20, 30, 40, 50, 60, 70, 80, 90, 100), which are arranged to move an elevator car (4) by means of a traction sheave (3), characterized in that at least one of the aforementioned ropes (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) is according to any of the preceding claims 1-14.

16. Rope arrangement (R) of a hoisting device according to claim 15, characterized in that the hoisting device is a passenger and/or freight elevator.

17. Rope arrangement (R) of a hoisting device according to claim 15, characterized in that all the ropes of the aforementioned ropes (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) are according to any one of the preceding claims 1-10.

18. Elevator, which comprises an elevator car (4), a traction sheave (3), a power source for rotating the traction sheave (3), characterized in that it comprises a rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) according to any of claims 1-14 and/or a rope arrangement (R) according to claim 15, and in that the elevator car (4) is arranged to be moved by means of the aforementioned rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) and/or rope arrangement (R).

19. Elevator according to claim 18, characterized in that the elevator is a passenger elevator and/or a freight elevator.

20. Elevator according to claim 18, characterized in that the rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) and/or rope arrangement (R) is arranged to move the elevator car (4) and counterweight (5).

21. Elevator according to any of claims 18-20, characterized in that the aforementioned rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) is an overspeed governor rope and/or a compensating rope.

22. Elevator according to any of claims 18-20, characterized in that the elevator comprises means for monitoring the condition of the aforementioned optical fibers and/or fiber bundles (2) comprising several optical fibers, which means monitor the strain and/or displacement and/or condition of the aforementioned optical fibers and/or fiber bundles (2) from the load-bearing part (11, 21, 31, 41, 51, 61, 71, 81, 91) of the rope.

23. A method for condition monitoring of a rope for a hoisting device, characterized in that in the method the condition of the rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) and/or the roping (R) is monitored by monitoring the condition of the optical fibres and/or fibre bundles (2), and if it is detected that the strain and/or displacement of the optical fibres and/or fibre bundles (2) has increased and/or that the same condition has decreased within a certain predetermined limit value, the need for replacing or overhauling one or more ropes is judged and a rope replacement or rope repair work is started, said optical fibres and/or fibre bundles (2) comprising a sensor fibre (2a) and a reference fibre (2b), by means of which common mode errors caused by temperature changes are eliminated.

24. Method according to claim 23, characterized in that the hoisting means are passenger elevators and/or freight elevators.

25. Method according to claim 23, characterized in that the rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) is according to any of the preceding claims 1-14 and/or the rope arrangement (R) is according to claim 15.

26. Method according to any of the preceding claims 23-25, characterized in that a single-mode or multimode optical fibre is used as the sensor fibre of the above-mentioned optical fibre or fibre bundle (2), the input of the light pulses taking place by means of a laser transmitter, or by means of a light-emitting diode light source.

27. A method according to claim 26, wherein the laser transmitter is a semiconductor laser.

28. Method according to any of the preceding claims 23-25, characterized in that the aforementioned optical fibre and/or fibre bundle (2) comprises a Fabry-perot-type sensor fibre, by means of which, in the method, the strain and/or displacement of the rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) is measured.

29. Method according to any of the preceding claims 23-25, characterized in that the aforementioned optical fiber and/or fiber bundle (2) comprises a sensor fiber comprising a bragg grating structure by means of which, in the method, the strain and/or displacement of the rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) is measured.

30. Method according to any of the preceding claims 23-25, characterized in that the aforementioned optical fibre and/or fibre bundle (2) comprises a sensor fibre, which functions as a brillouin distributed fibre sensor, by means of which sensor fibre the strain and/or displacement of the rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) is measured in the method.

31. Method according to any of the preceding claims 23-25, characterized in that the aforementioned optical fibre and/or fibre bundle (2) comprises a sensor fibre, in which the transit time of a light pulse is measured, by means of which sensor fibre the strain and/or displacement of the rope (10, 20, 30, 40, 50, 60, 70, 80, 90, 100) is measured in the method.

32. Method according to any of the preceding claims 23-25, characterized in that in the method the transit time and/or strain of the light pulse is measured in several ropes (10, 20, 30, 40, 50, 60, 70, 80, 90, 100), and when the above-mentioned rope measurements differ from each other completely, the need for replacing or overhauling one or more ropes is judged and a rope replacement work or a rope repair work is started.