WO2005108672A1

WO2005108672A1 - Cable and belt for a lift speed limiter and associated pulleys

Info

Publication number: WO2005108672A1
Application number: PCT/ES2004/000331
Authority: WO
Inventors: Iñaki ARANBURU AGIRRE; Miguel Angel Madoz Michaus; Juan Manuel PAGALDAY ERAÑA
Original assignee: Orona, S. Coop.
Priority date: 2004-05-10
Filing date: 2004-07-12
Publication date: 2005-11-17
Also published as: JP2007536186A; EP1748104A1; RU2006143639A; BRPI0418768B1; ES2253981B1; PT1748104E; ES2253981A1; ES2379353T3; EP1748104B1; KR20070047242A; CN1973082A; ATE546583T1; US20070221452A1; MXPA06012983A; BRPI0418768A; CN1973082B

Abstract

The invention relates to a cable and belt which are intended for lift speed limiters and to the associated pulleys. The inventive cable comprises high-strength steel wires which are grouped into strands which together form a core. The core is completely coated with a polymer material which is introduced into the cavities between the aforementioned strands, such as to produce an outer polymer surface having a diameter that is slightly greater than that of the core. According to the invention, the belts combine at least two metal cables comprising high-strength steel wires which are completely coated with a polymer material. The pulleys designed for said cables are semicircular or semicircular and equipped with a notch, having a reduced diameter, low aggressiveness and good adhesion, such as to provide a high coefficient of friction between the coated cable and the pulley, thereby conferring on the cable its high resistance to fatigue caused by bending and wear.

Description

CABLE AND TAPE FOR ASSOCIATED ASCENSOR AND PULLEY SPEED LIMITER

D E S C R I P C I Ó N

OBJECT OF THE INVENTION

The present invention relates to a cable, a belt and its associated pulleys, which are applicable to a speed limiting system for lifting installations whose function is to transmit the effort from the speed limiting system to the mechanical means in charge of stop the elevator with its travelers before any uncontrolled movement.

It is an object of the invention that the cable or tape has a high tensile strength to reduce the diameter of said cable without compromising the reliability of operation of the limiter and therefore of the installation, being able to use voltage transmitting elements (cables or tapes) lighter, cheaper and manageable, and in general limiting systems also of reduced size, weight and cost.

It is also the object of the invention that the cable or belt have a great resistance to fatigue under bending cycles such as those that occur when passing through the pulley (s) included in the limiting system to reduce the diameter of said pulleys and thus reduce the space occupied by the limiter, gaining space occupied by the installation in the hollow and by extension in the building, reduce the weight of all components, as well as ensure that the reliability of the systems is higher by turning the pulley to greater speed. It is another object of the invention that the cable or tape has a friction coefficient with the limiter pulley clearly superior to that of conventional systems to use pulleys with less aggressive throats while maintaining the necessary traction capacity in the pulley, thereby it achieves that the cable or tape is less punished by said pulley, increasing its useful life, being able to become a maintenance free system.

BACKGROUND OF THE INVENTION

The speed-limiting elements usually consist of a pulley attached to a fixed axis through which a cable passes, whose points are attached to the element whose safety is to be protected and which also has a second pulley attached to a second fixed point in the other end of the hole, which is used to tension the connection cable. Thus, the first of the described pulleys rotates at a speed w given by: w = v / R Where v is the linear speed of the cabin or counterweight to be controlled, and R is the radius of the limiter pulley. The safety device trips when w exceeds a preset value.

The reduction of the radius R of the pulley makes the speed of rotation of the safety element higher, which makes the setting of the pulley easier, since with the usual speeds and diameters the setting of these elements, especially in Low speeds are complex, with specific speed-limiting elements usual for lower nominal speeds av = 0.5 m / s. Currently, speed limiters are preferably mounted in two types of configurations:

In a first type of configuration, which has been the most traditionally used, a speed limiter system is located at a fixed point in the installation. The limiting system has a main pulley on which the cable in charge of transmitting the actuation effort circulates, and it can also have deflection pulleys. They also have tension pulleys that guarantee a tension in the system cable. After passing through the whole set of pulleys, the cable is finally fixed to the traveling element whose over speed is to be protected. This voltage will be at least that necessary so that at the time the system is activated, the cable (usually by friction in the throat of the limiting system) is capable of transmitting the necessary effort to the component responsible for stopping the traveling group (usually parachutes whose activation stops and keeps the traveling group to the elevator guides). The cable therefore makes a closed loop that is born and dies in the traveling group, so that the linear movement of the traveling group produces the rotation of the pulleys of the limiting system and the deflection pulleys.

In other configurations, such as those described in EP Patents 1175367 Bl of Thyssen rupp elevator Manufacturing (France), WO 03070615 Al of JUNG, Insook (Korea) and WO 03091142 Al of Mitsubishi Denki Kabushikikaisha (Japan), the limiter is attached in solidarity with the element to be controlled (traveling group) and the cable is arranged in a single length, with a weight on the lower tip which is the one that provides tension to it. In this case also the translation of the element mobile spins the speed limiter system. This same limiting system is capable of activating the parachute element on its own, that is, by means of a turn and a translation that would occur in the limiting element in the event of overspeed, translation and / or rotation movements would occur in the limiting system that would directly activate the parachute element. This configuration allows to obtain an angle of hugging of the cable on the pulley of values between 180 and 300 ° increasing the traction capacity (T1 / T2) of the system. There are other devices that use fixed elements such as the installation guides described in patent No. US645756 by James M. Draper et. to the. To date, traditional cables used in speed-limiting systems must have a minimum diameter d = 6 mm that is determined by regulatory considerations, as well as the D / d ratio greater than or equal to 30, where D is the diameter of the pulley, which determines the minimum value of D = 180 mm, and consequently the overall size of the device.

There are different lifting applications for cables such as those described in the present invention that are described for tensile cables in European Patent EP 1273695, and even for non-round section tensile elements, such as those described in WO 9942589, WO 9943885, WO 0037738 AND WO 0114630. The activation of the braking elements of Emergency (Parachute) requires that the limiter exert a minimum force on said elements, which is 300 N or twice the force necessary to activate the braking elements. This makes it necessary to use aggressive throats that ensure adherence in conventional systems, which is achieved by carving the throats of the pulley of the limiter system with shapes, usually semi-sealed with BETA throat angles between 100 ° and 105 °, and in " V "with notch or" V "without notch with GAMMA throat angles between 35 and 40 °, the latter needing a surface hardening process to reach hardness around 50 HRC or higher. This process is expensive because it requires specific materials, due to its nature and due to the quality control required after applying it. The use of this type of throats means an inevitable degradation of the throats of the pulleys of the limiting systems and of the cable, forcing periodically to replace these components, which is expensive and if it is not done with care it can produce dangerous situations in the installation. Speed limiting systems are subject to Certification and CE marking, which complicates administrative work in case of replacement before the competent notified bodies.

On the other hand, the use of large pulleys causes the limiters to rotate at relatively low speeds, which translates into a slow movement of the elements that have to produce their activation and low kinetic energies, which makes it difficult to tare them especially in centrifugal type limiters.

DESCRIPTION OF THE INVENTION The present invention relates to a cable or ribbon of high-strength steel wires coated with a polymeric material, for example polyurethane, for speed limiters that detect overspeed in lifting installations and transmit the effort necessary to activate the means. emergency braking associated with said lifting facilities. The use of high resistance cables in speed limiters allows the cable diameter to be reduced while maintaining a high level of safety. A conventional system incorporates a cable of diameter d = 6 mm or greater, the metallic cable object of the present invention shows an outer diameter of less than 5 mm and is composed of wires of resistance greater than 2,000 N / mm ² .

The threads can be grouped in turn into cords, which are grouped around a central cord consisting of threads or a high-strength textile or synthetic material such as Kevlar.

The cable configurations can be multiple presenting some greater flexibility than others, and some better use of the cross section than others, but in any case the present invention can be carried out with any of them. In the case of tapes, the present invention contemplates that they have at least two metal cables comprising high-strength steel wires greater than 2000 N / mm ² grouped in cords that form a metal core with a diameter between 0.01 and 2 mm and that are completely covered by a material polymeric It is envisioned that the outer surface of polymeric material of the tape can be a flat surface or a corrugated surface. By using a cable or tape as described above, the safety system pulley can have a reduced diameter. The reduction of the diameter of the pulley of the safety system makes all of it small in size, managing to occupy less space in the hole and also in the building. The reduction in size also makes all components have a lower weight and lower price. A traditional system with metallic cable of nominal diameter d = 6 mm. It has a primitive pulley diameter D = 180 mm. or higher. The present invention has a correct operation with acceptable safety levels or higher than said traditional systems with primitive pulley diameters smaller than or equal to 150 mm in the case of a circular section cable, and primitive diameters smaller than 100 mm in the case of tapes of any kind. kind.

On the other hand, high-strength steel cables allow a lower D / d ratio than usual while also maintaining an acceptable level of safety, which further contributes to the reduction of the pulley's primitive diameter D. In the current state From the technique we can see that the diameter of the pulley is subject to a minimum ratio D / d = 30. The present invention works an assembly formed by cable (or tape) and pulley, with the cable (or tape) provided with a coating of polymeric material. Thanks to this polymeric cover, the coefficient of friction between the materials of cable (or tape) and pulley is much higher than the traditional systems being able to use flat surfaces for the belts and pulleys with semicircular throats for round cable obtaining internal pressures in the cable clearly lower than those of a traditional system. This allows the parameter D / d to be lowered to values below 30, achieving safety levels equal to or greater than conventional systems with ratios between 20 and 30. In addition, using this type of cables or tapes, the lubricant remains inside and does not disperse by the installation with the passage of time and the course of the cycles of the cable on the pulley contributing to better lubricate the inner wires and cords increasing the fatigue resistance of the cable + limiter system. The polymeric cover prevents the metallic outer cords from rubbing against the throat of the pulley avoiding any abrasion and wear of the outer threads thanks to the intermediate layer of elastic material increasing the life of the cable and the pulley to levels that in practice involve a system free of mantenimient.

In the present invention the use of round cable entails the use of a flat, convex or concave surface pulley. The said round cable can be used with different throat geometries, but the fact of being a cable covered with a polymeric material gives it a high coefficient of friction with the throat of the pulley of the speed limiting element to which it is associated, which It means that especially low aggressive throats can be used with the cable, such as semicircular or semicircular rounded. The use of this type of throats causes the life of the cable to be prolonged, since the pressure between cable and pulley is distributed more evenly than with other geometries, and there are no areas of pressure concentrations that can damage the cable afterwards. of a number reduced cycles This makes the expected life of the cable much higher, and allows reducing or even eliminating the cost of maintenance activities. This is in contrast to conventional limiting systems, which have semi-sealed and "V" throats in their pulleys, similar to those used in the traction pulley throats and therefore will suffer wear, and inspection and maintenance work is necessary to guarantee traction capacity of the limiting system and therefore its replacement before excessive levels of wear. The present limiting system, thanks to the design and the materials used, avoids any possible wear of the throat of the pulley of the limiting system, guaranteeing an effective life much greater than conventional systems and minimizing maintenance work, even being able to become free of mantenimient. The pulleys of the limiting element used for a cable may be of metallic material or not, with a semicircular or semicircular design with a notch with a BETA throat angle = 0 ^or and an arc of hugging the cable on the pulley ALFA = 25-50 °. In the case of the belt, the pulleys can be flat, concave or convex.

Thus, the diameter of the metal core of the cable is acceptable at values less than or equal to 5 mm, preferably between d = 2 and 4 mm and the primitive diameter of the pulley of the limiting element is acceptable at values less than or equal to 150 mm, preferably between D = 75 and D = 100 mm.

In the case of flat belts, these have a minimum of two internal metal cables with a diameter between d = 0.01 and 2 mm, and a primitive pulley diameter less than or equal to 100 mm.

In a possible alternative embodiment, it is contemplated that the pulley can be formed of metallic material and has a synthetic material coating on its throat and that the metallic cable lacks any coating.

DESCRIPTION OF THE DRAWINGS

To complement the description that is being made and in order to help a better understanding of the characteristics of the invention, according to a preferred example of practical implementation thereof, a set of drawings is attached as an integral part of said description. where illustrative and non-limiting, the following has been represented: Figure 1.- Shows a section of a type of cable.

Figure 2.- Represents another possible section of cable, in which the central cord has been replaced by a central cord of textile material or high strength material, such as Kevlar or another.

Figure 3. - Represents the cable shown in Figure 1 as it passes through two pulleys with different types of throats, in this case semicircular or semicircular grooves with notch.

Figures 4a to 4c- Shows different possible cable configurations. Figures 4d to 4e.- They show different possible tape settings.

Figure 5.- Represents possible configurations of the speed limiter system in which the cable loop is born and dies in the parachute element located in the chassis of the traveling group, although other configurations are possible without the main characteristics of the system being affected. . The speed limiting element is at a fixed point in the installation.

Figure 6.- Represents possible configurations of the speed limiter system in which the cable loop is born and dies in the parachute element located in the chassis of the traveling group, although other configurations are possible without the main characteristics of the system being affected. . In this case, the limiting element travels in solidarity with the traveling group.

Figure 7.- Represents possible configurations of the cable tension element although other configurations are possible without the main characteristics of the system being affected.

Figure 8.- Represents a speed limiting system in which the speed limiting element travels in solidarity with the traveling group but unlike the systems mentioned above, the effort transmitted to the parachute element is made by the same limiting element directly. The cable in this case has the function of rotating the pulley of the limiting element to detect in this way the linear speed at which the elevator travels, generate the signal in the event of an overspeed event and provide the necessary force to the limiting element to activate the element parachute Figure 9.- Represents the scheme of forces that they come into play at the time of action of the limiting system.

Figure 10.- Represents another possibility of the second type of limiting system.

PREFERRED EMBODIMENT OF THE INVENTION

Figure 1 shows a cable of metallic wires covered by a layer of polymeric material. The cable comprises a set of metallic wires (1), usually of steel, which are grouped according to certain geometric configurations of section that are then rotated to form a propeller, a cord (3) being constructed. The threads (1) that make up a cord (3) can be the same, as shown in Figure 1, or different. It is common for threads to be grouped concentrically forming layers. The different cords (3) are grouped in turn following a grouping scheme parallel to that described in the previous paragraph, that is, having a certain shape in a section and then turning to form a helix of cords just like a cord shape using a propeller of threads.

Figure 1 shows the strands of threads distributed around a central strand of threads, while in Figure 2 the central metallic strand has been replaced by a central strand (4) of textile or synthetic material of high resistance like the Kevlar or another.

The metal core of the cable formed by the grouping of cords (3) is surrounded by a coating of polymeric material (2), for example polyurethane, which has a circular outer section with an approximate diameter but somewhat larger than the larger diameter of the metal core and therefore completely covers it without significantly increasing the diameter of the core.

Figure 3 represents the cable shown in Figure 1 as it passes through the throats (5, 5 ') of different metal pulleys (2, 2') belonging to a speed limiter of those used in lifting devices. These pulleys can have different throat geometries (5, 5 '), although given the characteristics of the cable object of the invention it is preferable to use them in less aggressive throats such as semicircular throats (5) or semicircular grooves with notch (5') -

In figure 4c, a configuration can be seen in which the diameter of the central cord of the metal part of the cable is larger than the outer cords. This fact guarantees that the polymeric material penetrates between the spaces generated between the outer cords increasing the integrity of the system, the physical union between the metallic part and the polymeric material of the roof.

A comparison is then made between the characteristic parameters related to cable pulley assemblies used in conventional speed limiters with those corresponding to cable pulley assemblies object of the present invention.

The throats commonly used in the conventional speed limiter element are semicircular type with notch with BETA throat angles between 100 ° and 105 °, "V" throats with or without treatment of surface hardening with a GAMMA throat angle between 35 and 40 °.

In a conventional system with semi-sealed throat pulley with a BETA throat angle = 105 ° and a primitive diameter of 200 mm, it causes a specific pressure in the cable with a value between 3.5 and 7 N / mm ² depending on the tension coming from the tensioner pulley. With this configuration, friction coefficient values "f" of value between 0.4 and 0.5 are reached

(considering a coefficient of friction between the cable and the cast iron throat of μ = 0.2) achieving a tensile capacity of T1 / T2 values between 3.5 and 4. In a conventional system with throat pulley in

"V" of 40 ° not hardened and with an angle notch BETA = 105 ° and a primitive diameter of 200 mm, causes a specific pressure in the cable of a value between 4 and 8.5 N / mm ² depending on the tension coming of the tension pulley and the wear of the pulley throat. With this configuration, friction coefficient values "f" of a value between 0.5 and 0.6 are reached (considering a friction coefficient between the cable and the cast iron throat of μ = 0.2), achieving a tensile capacity of T1 / T2 values between 6 and 6.5.

In a conventional system with a "V" throat with a hardened GAMMA angle = 40 ° and a primitive diameter of 200 mm, it causes a specific pressure in the cable of a value between 3.5 and 6.5 N / mm ² depending on the tension coming from the tension pulley. With this configuration, friction coefficient values "f" of a value between 0.5 and 0.6 are reached (considering a friction coefficient between the cable and the cast iron throat of μ = 0.2), achieving a tensile capacity of T1 / T2 of values between 6 and 6.5.

The present invention using flat belts with metal cables inside has specific pressures on said inner cables of a value between 3 and 5 times lower, under the same conditions of use as the practical cases described above to achieve a tensile capacity similar to the achieved in these examples. Preferably, the belt will have a minimum of two internal metal cables with a diameter of values between d = 0.01 and 2 mm, and the pulley of the limiting element would have a smooth, concave or convex surface with a primitive diameter of values smaller than or equal to 100 mm

The present invention using metallic cables with wires of a resistance greater than 2,000 N / mm ² , and covered with a polymer material, such as polyurethane, has a coefficient of friction higher than traditional systems reaching values greater than μ = 0.4 . Experimental trials have given superior results μ = 0.5. This gives the system a tensile capacity T1 / T2 of a value greater than 8, it being possible to reduce the tension on the cable and therefore decrease the specific pressure on the cable, increasing the effective life of the cable.

A limiting mechanism according to this invention that has a pulley of a semicircular groove material with an angle of winding of the cables on the pulley ALFA = 30 ° and a primitive diameter of the pulley of 200 mm causes a specific pressure in the metallic part of a cable of diameter d = 2 mm, of a value between 1.2 and 1.5 N / mm ² depending on the tension coming from the tension pulley, which in this If the case would be lower than that normally used in conventional systems, this value is clearly lower than those achieved in conventional systems, this fact together with the benefits of being a covered cable would guarantee an effective life of the maintenance-free limiting system.

A limiting mechanism according to this invention that has a pulley of a semicircular groove casting material with an ALFA angle = 30 ° and a primitive diameter of 80 mm causes a specific pressure on the metal part of a cable of d = 2 mm, of a value between 3 and 4 N / mm ² depending on the tension coming from the tension pulley, which in this case would be lower than that usually used in conventional systems. This value is similar or lower than those obtained in traditional systems, this fact together with the benefits of being a covered cable would guarantee an effective life of the system similar or superior to a conventional limiting system.

A limiting system with a configuration like the one shown in Figure 6, in which the limiting system travels with the traveling assembly, but the cable is static with a fixed mooring point at the top and a weight at the bottom, with semicircular throat of an angle ALFA = 30 ° of a casting material and a primitive diameter of 80 mm, it causes a specific pressure on the metal part of a cable of d = 2 mm, of a value between 1 and 3 N / mm ² depending on the tension coming from the tension pulley, which in this case would be lower than the one normally used in conventional systems and even lower than the configurations described above. This value is lower than those obtained in traditional systems together with the benefits of being a covered cable would guarantee an effective system life superior to a conventional limiting system.

In figures 5 and 6 a metallic cable of a limiting system consisting of wires of resistance greater than 2,000 N / mm ^{2 appears} and whose outer diameter is less than or equal to 5 mm and is not covered with any material. This cable passes through the pulley throat of the limiting element that is metallic with a synthetic material cover, such as polyurethane or resins, with a design that increases the friction coefficient between cable and pulley.

As can be seen in Figure 9, the present invention requires a lower cable tension than conventional systems that usually need a voltage between G = 50 kg and 100 kg for configurations such as those shown in Figure 5 and between G = 25 kg and 50 kg for configurations such as those shown in Figure 6.

Looking at Figure 9, for the type of loop configuration, we get: Fl + GR + G / 2-T2 = 0

Considering experimental data pointing to Tl / T2 = 8, we need a tension in the cable of values between 10 and 12 kg, depending on the installation path. The weight of a cable or tape object of the present invention is lower than conventional cables and is between 0.04 and 0.1 kg / m. This fact makes the effects of inertia to move the mass of the cable in the acceleration and deceleration phases of the elevator smaller. Looking at Figure 9, for the type of configuration in which there is only one cable length, we get:

F1 + GR + G-T2 = 0 Considering experimental data pointing to

Tl / T2 = 10 (higher than the previous case because it is possible to increase the angle of hugging of the cable on the pulley of the limiting element), we need a tension in the cable of values between 5 and 8 kg, depending on the installation path . This tension is clearly lower than conventional systems, contributing to minimize the effects of inertia and reducing the specific pressure on the cable when passing through the pulleys. Accordingly, the present invention means in practice a virtually maintenance-free system.

The use of high-strength steel in the cables also contributes to extend the life of the cables, since their behavior to mechanical fatigue and wear improves, contributing to the effect described above.

Claims

1.- Cable for elevator speed limiter characterized in that it comprises high-strength steel wires (1) greater than 2000 N / mm ² grouped in cords (3) between which in turn they form a core with a diameter less than or equal to 5 mm which is completely covered by a polymeric material (2) that is introduced into the holes defined between cords (3) obtaining a polymeric outer surface with a diameter slightly larger than the diameter of the core.

2. Cable for speed limiter according to claim 1 characterized in that the diameter of the core is between 2 and 4 mm.

3. - Cable for speed limiter according to claims 1 characterized in that the core incorporates a central cord (4) of textile material.

4. - Cable for speed limiter according to claim 1 characterized in that the core incorporates a central cord (4) of composite material.

5.- Tape for speed limiter characterized in that it has at least two metallic cables comprising steel wires (1) of high resistance greater than 2000 N / mm ² grouped in cords (3) that form corresponding metal cores of diameter between 0.01mm and 2mm and they are completely covered by a polymeric material (2).

6. - Belt for speed limiter according to claim 5 characterized in that the outer surface of polymeric material of the belt consists of A flat surface.

7.- Belt for speed limiter according to claim 5 characterized in that the outer surface of polymeric material of the belt consists of a corrugated surface.

8. - Pulley for elevator speed limiter used with the cable described in claims 1 to 4 characterized in that it has a semi-circular design throat of high level of adhesion with BETA throat angle = 0 ° and an arc of cable hugging over The ALFA pulley between 25 and 50 °, as well as has a primitive diameter of 150 mm or less.

9. Pulley for elevator speed limiter according to claim 8 characterized in that the throat has a notch in its semicircular design.

10. Pulley for elevator speed limiter according to claim 8 characterized in that its primitive diameter is less than 100 mm.

11. Pulley for elevator speed limiter used with the belt described in claims 5 to 7 characterized in that its primitive diameter is less than or equal to 100 mm.

12.- Set consisting of cable and pulley for speed limiter characterized in that the pulley that has a coating layer of synthetic material in its throat and has a primitive diameter less than or equal to 150 mm, and because the cable comprises threads of high strength steel greater than 2000 N / mm ² grouped in cords between which in turn form a core of diameter less than or equal to 5 mm.