Classifications

• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B1/00—Constructional features of ropes or cables
  • D07B1/14—Ropes or cables with incorporated auxiliary elements, e.g. for marking, extending throughout the length of the rope or cable
  • D07B1/145—Ropes or cables with incorporated auxiliary elements, e.g. for marking, extending throughout the length of the rope or cable comprising elements for indicating or detecting the rope or cable status
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B1/00—Constructional features of ropes or cables
  • D07B1/14—Ropes or cables with incorporated auxiliary elements, e.g. for marking, extending throughout the length of the rope or cable
  • D07B1/147—Ropes or cables with incorporated auxiliary elements, e.g. for marking, extending throughout the length of the rope or cable comprising electric conductors or elements for information transfer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
  • B66B7/00—Other common features of elevators
  • B66B7/06—Arrangements of ropes or cables
  • B66B7/062—Belts
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B1/00—Constructional features of ropes or cables
  • D07B1/02—Ropes built-up from fibrous or filamentary material, e.g. of vegetable origin, of animal origin, regenerated cellulose, plastics
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B1/00—Constructional features of ropes or cables
  • D07B1/22—Flat or flat-sided ropes; Sets of ropes consisting of a series of parallel ropes
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2201/00—Ropes or cables
  • D07B2201/10—Rope or cable structures
  • D07B2201/1012—Rope or cable structures characterised by their internal structure
  • D07B2201/1014—Rope or cable structures characterised by their internal structure characterised by being laid or braided from several sub-ropes or sub-cables, e.g. hawsers
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2201/00—Ropes or cables
  • D07B2201/10—Rope or cable structures
  • D07B2201/1012—Rope or cable structures characterised by their internal structure
  • D07B2201/1016—Rope or cable structures characterised by their internal structure characterised by the use of different strands
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2201/00—Ropes or cables
  • D07B2201/20—Rope or cable components
  • D07B2201/2083—Jackets or coverings
  • D07B2201/2087—Jackets or coverings being of the coated type
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2201/00—Ropes or cables
  • D07B2201/20—Rope or cable components
  • D07B2201/2095—Auxiliary components, e.g. electric conductors or light guides
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2501/00—Application field
  • D07B2501/20—Application field related to ropes or cables

Definitions

• the invention relates to a belt with a plurality of synthetic fiber strands running at a distance and which are embedded in a belt casing.
• Such belts are particularly suitable for use as suspension means or propellants in an elevator installation.
• Running ropes are an important, highly stressed machine element in conveyor technology, especially in elevators, in crane construction and in mining.
• the stress on driven ropes, such as those used in elevator construction, is particularly complex.
• the cabin frame of a cabin guided in an elevator shaft and a counterweight are connected to one another by means of several steel strand cables.
• the ropes run over a traction sheave which is driven by a drive motor.
• the drive torque is applied to the rope section resting on the traction sheave via the wrap angle under frictional engagement.
• the ropes experience tensile, bending, compressive and torsional stresses. Depending on the situation, the resulting tensions have a negative impact on the rope condition. Due to the usually round cross-section of a steel strand rope, the rope can twist around the sheaves and is thus subjected to bending in the most varied of directions.
• Ropes made of aramid fibers have the same cross-section and the same load-bearing capacity compared to conventional steel ropes and only a quarter to a fifth of the specific rope weight. In contrast to steel, however, the aramid fiber has a much lower transverse strength in relation to the longitudinal load capacity due to the rectification of the molecular chains.
• Belts are mainly used by the automotive industry, for example as V-belts, or by the machine industry. Depending on
• Such a degree of stress is strengthened by such steel belts. These are usually endless belts. Monitoring an endless belt is relatively complex and is not used in the automotive sector for cost reasons. The automotive industry has therefore taken the path of enduring the belts used to ensure that a belt is replaced before it runs the risk of failure. Such a lifetime limitation is only suitable for large quantities, since the necessary preliminary examinations can be carried out here and for belts that are easy to replace.
• a toothed belt is a form-fitting, slip-free transmission medium that rotates synchronously with a drive pulley, for example.
• the load capacity of the teeth of the toothed belt and the number of teeth in engagement determine the transmission capacity.
• a lifespan limitation such as that specified by the automotive industry, is less suitable for a belt that is to be used as a carrying belt or propellant for an elevator.
• the aim of the invention is to provide a belt whose condition can be monitored.
• FIG. 1 shows a schematic view of an elevator installation with a car connected to a counterweight by means of a carrying strap according to the invention
• Figure 2A is a side view of a traction sheave with a portion of a belt according to the invention.
• FIG. 2B a cross-sectional view of a carrying strap, according to the invention.
• FIG. 3B an enlarged section of a cross-sectional view of a further carrying belt, according to the invention.
• Figure 5 is a cross-sectional view of a V-ribbed belt according to the invention.
• Figure 6 is a perspective view of a toothed belt according to the invention.
• a cabin guided in a shaft 1 hangs on a load-bearing belt 3 (support belt) according to the invention, which preferably comprises fiber bundles made of aramid fibers and which runs over a drive pulley 5 connected to a drive motor 4.
• a load-bearing belt 3 support belt
• the other end of the carrying belt 3 is fastened in the same way to a counterweight 7, which is also guided in the shaft 1.
• the arrangement shown is a so-called 1: 1 suspension, which is characterized in that the carrying strap 3 according to the invention only in one Direction is curved, since it only rotates around a single traction sheave 5 without being deflected over other sheaves, as would be the case, for example, with a 2: 1 suspension.
• the relatively low weight of carrying straps with plastic strands offers the advantage that the usual compensating belts can be partially or completely dispensed with in elevator systems.
• a compensating belt can also be provided despite the use of belts with light plastic strands.
• Such a compensating belt is then connected in a similar manner with its first end to the lower end of the cabin 2, from where the compensating belt leads to the counterweight 7, for example, via deflection rollers placed on the shaft floor 10.
• a monitoring system should be provided to increase the security of systems using belts. Studies have shown that monitoring the belt jacket does not provide reliable results. Cracks or fatigue in the strands, which can give the belt its longitudinal strength, may go unnoticed when monitoring the belt sheath alone and lead to a sudden failure of a belt.
• Direct monitoring of the strands therefore seems to be more suitable.
• the problem with such direct monitoring is that the bending expansions occurring in the belt when rotating around a traction sheave are relative are small.
• the belt thickness is usually chosen to be a relatively low value with regard to typical applications in elevator systems, compared, for example, with the thickness of a corresponding suspension cable with a round cross section suitable for the same application.
• a strand running in the belt experiences a much smaller bending stretch when circulating around a traction sheave under load than a strand in a correspondingly designed rope under the same load.
• a strap 13 according to the invention for use in an elevator installation is shown in FIGS. 2A to 2C.
• the belt 13 comprises at least two strands 12 with twisted synthetic fiber yarns that are used to absorb the force Are designed in the longitudinal direction.
• the strands 12 run parallel to one another and are arranged at a distance X from one another.
• the strands 12 are embedded in a common belt casing 15.
• At least one of the strands 12 comprises an electrically conductive indicator yarn 14, which is twisted together with the synthetic fiber yarns of the strand 12 and contains fibers (filaments) made of an electrically conductive material, for example made of carbon, hard metals such as tungsten carbide, boron or electrically conductive plastics.
• the indicator indicator yarn 14 is arranged outside the center of the strand 12, as can be seen in FIG. 2C.
• the elongation at break ( ⁇ u ⁇ t , m d ) of the indicator yarn 14 must be less than the elongation at break ( ⁇ u ⁇ t (support) of the individual synthetic fiber threads of the strand 12.
• the breaking elongation ⁇ u ⁇ t, ind un ⁇ 3 the elongation at break ⁇ u ⁇ t, ⁇ rag are material sizes.
• the indicator thread 14 should the indicator thread 14 to be contactable to an electrical monitoring of the integrity of the indicator - Allow yarn 14.
• the position of the indicator thread 24 within the strand 21 is selected such that the filaments of the indicator thread 24 tire or break earlier than a synthetic fiber strand of the strand 21.
• the indicator thread 24 lies on the outer circumference of the strand 21, specifically on the side of the belt 23 which is subjected to the greatest bending stress, as shown in FIG Hatching shown. This ensures that the indicator thread 24 is always subjected to a bending load that is at least as great as the greatest bending load of a synthetic fiber yarn of the strand 21.
• the synthetic fiber yarns are schematically indicated in FIG. 3A as circles with a white circumference. In the case of an arrangement according to FIG. 3A, it is sufficient to specify that the elongation at break ⁇ u ⁇ t , in d of the indicator yarn 24, is smaller than the elongation at break ⁇ u ⁇ t 25 embedded.
• FIG. 3B Another belt 33 according to the invention is shown in FIG. 3B.
• the indicator yarn 34 is located inside the strand 31 on one side from the strand center, which is in the direction of the side of the belt 33 which is subjected to the greatest bending stress, as shown in FIG. 3B with the hatching.
• the five hatched synthetic fiber strands experience a bending load that is greater than or equal to the bending load experienced by the indicator yarn 34.
• Strands 31 are embedded in a belt jacket 35.
• the elongation at break ⁇ u ⁇ t , md of the indicator thread 34 must be smaller by a factor A than the elongation at break ⁇ u ⁇ t , ⁇ rag of the individual synthetic fiber yarns of the strand 31, the factor A depending inter alia on the position of the indicator yarn 34 within the strand 31.
• the following condition typically applies to A: 0.2 ⁇ A ⁇ 0.9 and preferably 0.3 ⁇ A ⁇ 0.85.
• the material of the indicator yarns and the material of the synthetic fiber yarns of the strand must be selected such that the elongation at break ⁇ u ⁇ , i n d of the indicator yarns is less than the elongation at break ⁇ u ⁇ , ⁇ rag of the individual synthetic fiber yarns of the strand;
• the indicator thread must be twisted together with the synthetic fiber threads of the strand; the indicator yarn thus forms an intimate connection with the surrounding synthetic fiber yarns and is always subjected to a bending stress that is comparable to the bending stress of the surrounding synthetic fiber strands.
• the indicator yarn thus runs in a spiral along the longitudinal direction of the belt. If the indicator yarn is not on the outer circumference of the fiber bundle, the following additional condition applies:
• R Trag radial distance of the outermost synthetic fiber yarn, measured from the center of the strand (see Fig. 2C)
• the elongation at break ⁇ u ⁇ t , ⁇ n d for the indicator yarn as a function of the (characterized by Rm) position of the indicator yarn inside the strand must be selected so that the filaments of the Indicator yarns break earlier when the belt is loaded than the synthetic fiber yarns surrounding the indicator yarn of the corresponding strand.
• the factor 0.88 in the inequality is an empirical value, which is determined in such a way that the behavior of the indicator yarn can be concluded with sufficient certainty
• Breakage behavior of the synthetic fiber yarns is only valid if the indicator yarn is not in the center of the strand and the effect of the bending strains is therefore dominant for the breaking behavior of the indicator yarn. If the indicator yarn is located in the center or in the vicinity of the center of the strand, the breaking behavior of the indicator yarn is determined less by the bending elongations of the belt than by the tensile load. In the latter case, there are only conditions for the indicator yarn when the belt is loaded, that of loading a yarn in a straight line belt that is under tension or in a straight rope that is only under tension. In this limit case there is sufficient sensitivity of the indicator yarn if the inequality
• the limit value 0.88 is determined empirically to enable reliable conclusions to be drawn about damage to the synthetic fiber yarns.
• aramid synthetic fiber yarns can be used.
• Aramid has a high alternating bending strength and a high specific elongation at break ⁇ u ⁇ t / load .
• the strands of the belt can have opposite directions of rotation.
• carbon fibers have proven to be particularly suitable as filaments for the indicator yarn because they are brittle (ie small elongation at break ⁇ u ⁇ t , in) as aramid and because they are electrically conductive and can also be produced inexpensively.
• the belt jacket comprises a plastic material.
• plastic materials are particularly suitable as belt straps: rubber, neoprene rubber, polyurethane, polyolefin, polyvinyl chloride or polyamide.
• the belt casing can have a dumbbell-shaped, cylindrical, oval, concave, rectangular or wedge-shaped cross-sectional shape.
• FIG. 4 Another embodiment of the invention is shown in FIG. 4 as a schematic cross section.
• the belt 43 comprises a total of four strands 41 running parallel.
• Each strand 41 comprises a plurality of synthetic fiber yarns and one indicator yarn 44 each, which are twisted together.
• the indicator yarns 44 run in a helical manner along the longitudinal direction of the belt 43 in each strand 41.
• the indicator yarns 44 are from approximately 12 o'clock, 1 o'clock, 9 o'clock and 4 o'clock viewed from left to right. If you cut the same belt 43 at a different location, a different picture would result as to the position of the indicator yarns 44.
• the invention can be applied to all belts that have synthetic fiber strands for reinforcement.
• Examples are: flat belts, poly-V belts, V-ribbed belts 53 (as shown for example in FIG. 5), or (trapezoidal) toothed belts 63 (as shown for example in FIG. 6).
• a V-ribbed belt 53 according to the invention as shown in FIG. 5, has a large number of parallel strands 51 which are embedded in a belt casing 55.
• a trapezoidal toothed belt 63 according to the invention, as shown in FIG. 6, has a whole number of strands 61 running in parallel, which are embedded in a belt casing 65.
• a synthetic fiber strand can have several indicator yarns.
• the belt has a plurality of parallel strands.
• a first strand comprises a first indicator yarn, which has a first elongation at break ⁇ u ⁇ t , ini.
• a second strand comprises a second indicator yarn, which has a second elongation at break u ⁇ t , ind2.
• the first carbon fiber responds first because this first carbon fiber is more sensitive.
• a predetermined reaction can be triggered in this case For example, a service call can be made or elevator operation can be restricted If the second carbon fiber fails, for example, elevator operation can be stopped entirely.
• strands can also each contain an indicator yarn with the same elongation at break ⁇ u ⁇ t , ⁇ n and the increase in the number of failed strands serves as a trigger criterion for a suitable reaction.
• an indicator circuit can be used which uses measurement technology to determine whether the properties of a carbon fiber have changed or whether a carbon fiber has been interrupted. You can go to
• the carbon fibers of two fiber bundles are conductively connected to one another at one end of the belt.
• the indicator circuit can, for example, one or more comparators and one or more analog / digital Have converters that establish a connection to the usually digital elevator control.
• the invention enables for the first time a reliable and early detection of fatigue and breaks in the fiber bundles, which give a belt the load-bearing capacity. Such a belt can be replaced in good time.

Landscapes

• Lift-Guide Devices, And Elevator Ropes And Cables (AREA)
• Ropes Or Cables (AREA)
• Devices For Conveying Motion By Means Of Endless Flexible Members (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
• Slot Machines And Peripheral Devices (AREA)
• Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
• General Details Of Gearings (AREA)
• Control Of Conveyors (AREA)
• Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
• Purses, Travelling Bags, Baskets, Or Suitcases (AREA)
• Cable Accessories (AREA)
• Packages (AREA)
• Emergency Lowering Means (AREA)

Priority Applications (1)

Applications Claiming Priority (4)

Publications (2)

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Family Applications (1)

Country Status (19)

Families Citing this family (28)

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• 2003
  • 2003-09-27 MY MYPI20033692A patent/MY134592A/en unknown
  • 2003-10-10 BR BRPI0315360-6B1A patent/BR0315360B1/pt not_active IP Right Cessation
  • 2003-10-10 DK DK03808834T patent/DK1554428T3/da active
  • 2003-10-10 JP JP2004544581A patent/JP2006508004A/ja active Pending
  • 2003-10-10 ES ES03808834T patent/ES2285258T3/es not_active Expired - Lifetime
  • 2003-10-10 AU AU2003264823A patent/AU2003264823B2/en not_active Ceased
  • 2003-10-10 EP EP03808834A patent/EP1554428B1/fr not_active Expired - Lifetime
  • 2003-10-10 PT PT03808834T patent/PT1554428E/pt unknown
  • 2003-10-10 AT AT03808834T patent/ATE357554T1/de active
  • 2003-10-10 KR KR1020057006662A patent/KR101128313B1/ko not_active IP Right Cessation
  • 2003-10-10 WO PCT/IB2003/004482 patent/WO2004035913A1/fr active IP Right Grant
  • 2003-10-10 MX MXPA05004030A patent/MXPA05004030A/es active IP Right Grant
  • 2003-10-10 CN CN200380101388A patent/CN100580176C/zh not_active Expired - Fee Related
  • 2003-10-10 NZ NZ539247A patent/NZ539247A/en not_active IP Right Cessation
  • 2003-10-10 CA CA2500437A patent/CA2500437C/fr not_active Expired - Fee Related
  • 2003-10-10 DE DE50306867T patent/DE50306867D1/de not_active Expired - Lifetime
• 2005
  • 2005-04-15 US US11/106,759 patent/US7326139B2/en active Active
  • 2005-05-13 NO NO20052371A patent/NO325262B1/no not_active IP Right Cessation
• 2006
  • 2006-01-18 HK HK06100799A patent/HK1080914A1/xx not_active IP Right Cessation

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