This application claims priority to European Patent Application No. EP14198544.0 filed on Dec. 17, 2014, the entire contents of which are incorporated herein by reference.
The invention relates to storing and installing of one or more elevator ropes. The rope is, in particular, a rope for an elevator meant for transporting passengers and/or goods. The rope may be a suspension rope for suspending the elevator car, for instance.
Storing of a rope may be needed in various stages of its lifetime. The storing is conventionally implemented by forming a rope reel of the rope so that it can be stored and/or transported as a compact unit. In the field of elevators, storing is usually needed for transporting the rope to the site, and further to the specific installation location where the rope can be unwound and installed in the elevator.
Ropes are typically irreversibly flexible such that after bending the rope into a curve, it does not reverse back to its original form by itself. These kinds of ropes usually comprise load bearing members made of twisted wires or equivalents. This kind of rope is easy to wind around a drum where it can be stored until a later unwinding. Also such ropes exist, which are rod-like and have a straight form when in rest state. This type of rope is presented in patent publication WO2009090299 A1. This type of ropes are relatively rigid, but elastically bendable, and the rope self-reverses back to a straight form from bent form in rest state, i.e. after all bending directed to it ceases. A known way to store this kind of ropes has been to form a rope reel from the rope by winding it around a drum and subsequently tying the rope end against the outer rim of the rope reel so that the rope reel cannot unwind.
The known methods described above have caused difficulties in later unwinding process. In particular, after releasing the rope end, the rope end has been difficult to control. This has been the case particularly with ropes that are elastically bendable and tending to reverse towards straight form after bending. It has been found out that the bending tension is prone to cause difficulties in unwinding of the rope the more rigid the elastically bendable ropes are. The rope tends to straighten as an effect of said bending tension and may easily escape from the hands of the person preparing the unwinding operation. Avoiding this type of events has necessitated auxiliary means or personnel for controlling the rope end once it has been freed from the reel.
The object of the invention is to introduce an improved rope storage unit and an improved method for installing of an elevator rope. An object is, more particularly, to introduce a rope storage unit wherein rope can be stored and wherefrom it can be subsequently unwound without damaging it, all this in a simple and efficient way. Further, an object is to introduce a method for installing of an elevator rope, which is simple to carry out and does not jeopardize condition of the ropes. The object is particularly to introduce a rope storage unit and a method well suitable for a rope, which is elastically bendable and thereby difficult to handle. With the invention, inter alia, one or more of the previously described drawbacks of known solutions and problems discussed later in the description of the invention, can be alleviated. Advantageous embodiments are presented, inter alia, which are well suitable for a rope having sensitive surface material.
It is brought forward a new rope storage unit, comprising a rope reel, formed by a rope wound in a spiral form and having a central axis, and delimiting a central space inside the rope reel, the rope having an end protruding from the inner rim of the rope reel; and a support body provided with an inner space inside which the rope reel is positioned, the support body comprising a side face plate, which side face plate delimits the inner space in axial direction of the rope reel and comprises an opening extending through it; and a guide collar for guiding the rope end away from the central space without contacting the side face plate, which guide collar is mounted on the side plate and borders the opening thereof, the guide collar delimiting a guide opening that leads away from the central space of the rope reel. Hereby, it is provided that the rope is unwindable by moving rope away from the rope reel via said central space and through the opening of the guide collar such that it slides against the surface of the collar. With this configuration, the rope can be stored in a controlled and efficient fashion as well as subsequently unwinded both in a controlled and gentle fashion without touching the side plate. The rope storage unit defined is well suitable for a rope which is elastically bendable and thereby difficult to handle during unwinding process. The gentleness of the guidance of the rope during its unwinding process can be ensured, because the material and shape of the guide collar can be optimized for the purpose of rope guidance independently of the material and shape of the side plate.
In a preferred embodiment, the side plate and the guide collar are made of different materials. Thereby, the material properties of the surface guiding the rope are not limited to be the same as those of the side plate.
In a preferred embodiment, the side plate is made of wood-based plate material, most preferably of fiberboard or plywood. Wood is a cheap and ecological choice of material, but without the collar its edges could in time get splintered or sharpen so that the rope sliding against it would be damaged.
In a preferred embodiment, the guide collar is made of polymer material, such as plastic or rubber. Said plastic is preferably Polyethylene or Polytetrafluoroethylene (PTFE).
In a preferred embodiment, the guide opening is circular. Then, the internal edge of the guide collar is circular and serves as a circular guide edge for the rope, any point of which circular internal edge (along its circumference) can guide the rope. Preferably, the circular guide opening is positioned coaxially with the rope reel.
In a preferred embodiment, the guide collar is flexible. More specifically, the guide collar is flexible such that it can flex under the pressure of the rope resting against it. Thereby, contact between the rope and the guide collar is made very gentle, because the guide collar can adapt to changes of pressure exerted on it by the rope. Thus, peaks of contact pressure between the rope and the guide collar can be smoothened, which reduces likelihood of excessive friction between those two.
Preferably, the guide collar has a flexible lip forming the internal edge of the guide collar and delimiting said guide opening.
In a preferred embodiment, the guide collar, in particular the flexible lip thereof, is flexible in axial direction of the rope reel. Then, the lip can flex such that the tip thereof moves outwards from the central space.
In a preferred embodiment, the guide collar is a flange, which is substantially flat in axial direction of the rope reel.
In a preferred embodiment, the rope is belt-shaped, and the rope is wound in said spiral form by bending it around an axis extending in width-direction of the rope. Thus, the rope settles easily in the spiral form and formation of twist can be avoided.
In a preferred embodiment, the rope is under substantial bending tension in said spiral form.
In a preferred embodiment, the rope is a rod having a straight form when in rest state and elastically bendable away from the straight form, the rope being under substantial bending tension in said spiral form.
In a preferred embodiment, the outer rim of the rope reel radially compresses against structures surrounding it radially as an effect of said bending tension. Said structures surrounding the rope reel are arranged to delimit the radius of the rope reel from expanding, and thereby to block the rope of the reel from straightening.
In a preferred embodiment, the rope is wound in a spiral form with several rope rounds, including at least an outermost rope round having an outer rim radially compressing against said structures surrounding the rope reel radially as an effect of said bending tension, as well as several inner rope rounds each having an outer rim radially compressing, as an effect of said bending tension, against the inner rim of the rope round next to it in radial direction.
In a preferred embodiment, the support body comprises one or more support members delimiting said inner space and surrounding radially said rope reel.
In a preferred embodiment, said rope comprises one or more load bearing members embedded in a polymer coating forming the surface of the rope. The collar is in this case advantageous for protecting the coating from damages. The coating may be made of elastomer, such as polyurethane.
In a preferred embodiment, the opening of the collar is smaller than the central space as measured in radial direction of the rope reel. When the opening is large, the rope can be guided through it with only minor amount of twist. The large size of the opening also alleviates wear and other friction-related problems as the frictional contact is distributed along a vaster area. For ropes suitable for elevator use, it is preferable that the diameter of the opening is at least 30 cm. Most preferably, the diameter of the opening is in the range from 30 to 100 cm.
In a preferred embodiment, said structures surrounding the rope reel radially are in supporting contact with the outer rim of the rope reel along at least majority of the rim of the rope reel.
In a preferred embodiment, the support body comprises a support shaft via which the rope storage unit can be rotatably mounted.
In a preferred embodiment, the rope is wound in a spiral form with several rope rounds, including at least a radially outermost rope round, and a radially innermost rope round, the rope being unwindable round by round starting from the innermost rope round.
In a preferred embodiment, the rope is wound in a spiral form with several rope rounds, intermediate rope rounds between the innermost and outermost rope rounds, the intermediate rounds radially compressing against the next outer round as an effect of said bending tension.
It is also brought forward a new method for installing an elevator rope, comprising the steps of providing a rope storage unit as described anywhere above; and unwinding the rope from the rope storage unit; and connecting the rope to one or more movable elevator units, said units including at least an elevator car and preferably also a counterweight.
In a preferred embodiment, the rope is wound in a spiral form with several rope rounds, including at least an radially outermost rope round, and a radially innermost rope round, and in said unwinding the rope is unwound round by round starting from the innermost rope round.
In a preferred embodiment, said unwinding comprises moving rope away from the rope reel via said central space and through the opening of the guide collar such that it slides against the surface of the collar.
In a preferred embodiment, said unwinding comprises rotating the support body.
In a preferred embodiment said rope comprises one or more load bearing members made of composite material comprising reinforcing fibers embedded in polymer matrix. This kind of structure facilitates good load supporting properties, but also requires a great force to bend the rope into spiral form, which causes a great bending tension. Thereby, the storing solution as disclosed is especially advantageous with this rope. Said reinforcing fibers are preferably carbon fibers. These fibers facilitate rope lightness and tensile stiffness, thereby making the rope well suitable for elevator use. In this case especially, a great force to bend the rope into spiral form is required. Thereby, the disclosed solution alleviating challenges in storing and installation is especially advantageous with this rope.
In a preferred embodiment the rope reel is formed by the rope wound in a two-dimensional spiral form.
In a preferred embodiment that the rope reel is formed by the rope wound in a three-dimensional spiral form.
In a preferred embodiment each of said load bearing member(s) has width larger than thickness thereof as measured in width-direction of the rope.
In a preferred embodiment, said rope comprises one or more load bearing members extending parallel to the longitudinal direction of the rope unbroken throughout the length of the rope, which one or more load bearing members is/are made of composite material comprising reinforcing fibers in polymer matrix, said reinforcing fibers preferably being carbon fibers. Said reinforcing fibers are preferably carbon fibers due to their excellent properties in elevator use, but alternatively some also other fibers could be used, such as glass fibers. With carbon fibers, the tendency to straighten is particularly strong, whereby in this context the measures for alleviating the problems of straightening of rope during installation are particularly advantageous. It is preferable that also said reinforcing fibers are parallel with the length direction of the rope. The straight structure facilitates further the longitudinal stiffness of the rope, but increases bending rigidity, whereby a great force to bend the rope into spiral form is required. Thereby, the disclosed solution alleviating challenges in storing and installation is especially advantageous with this kind of rope.
In a preferred embodiment, the reinforcing fibers of each load bearing member are distributed in the polymer matrix of the load bearing member in question and bound together by it. The reinforcing fibers of each load bearing member are then preferably substantially evenly distributed in the polymer matrix of the load bearing member in question. Furthermore, preferably, over 50% of the cross-sectional square area of the load bearing member consists of said reinforcing fibers. Thereby, a high tensile stiffness can be facilitated. Preferably, the load bearing members cover together over proportion 50% of the cross-section of the rope.
In a preferred embodiment, the module of elasticity E of the polymer matrix is over 2 GPa, most preferably over 2.5 GPa, yet more preferably in the range 2.5-10 GPa, most preferably of all in the range 2.5-3.5 GPa. In this way a structure is achieved wherein the matrix essentially supports the reinforcing fibers, in particular from buckling. One advantage, among others, is a longer service life. With this kind of material of the load bearing members, the tendency to straighten is particularly strong, whereby in this context the measures for alleviating the problems of straightening of rope during storing and installation are particularly advantageous.
In a preferred embodiment the load bearing member(s) of the rope cover(s) majority, preferably 70% or over, more preferably 75% or over, most preferably 80% or over, most preferably 85% or over, of the width of the cross-section of the rope. In this way at least majority of the width of the rope will be effectively utilized and the rope can be formed to be light and thin in the bending direction for reducing the bending tension.
The rope storage unit is preferably a movable storage unit so that the rope can be transported within the rope storage unit to an installation site of an elevator, for instance. Preferably the rope storage unit is of a size and weight transportable with a fork lift.
The elevator described anywhere above is preferably an elevator for transporting passengers and/or goods. For this purpose, it comprises a car arranged to serve two or more landings. The car preferably is arranged to respond to calls from landing(s) and/or destination commands from inside the car so as to serve persons on the landing(s) and/or inside the elevator car.
In the following, the present invention will be described in more detail by way of example and with reference to the attached drawings, in which
The foregoing aspects, features and advantages of the invention will be apparent from the drawings and the detailed description related thereto.
The guide opening 21 defined by the internal edge of the guide collar 20 is preferably circular, as made visible in the preferred embodiment of
The material of the collar 20 is preferably such that the rope 3,3′,3″,3′″ can easily slide against the collar 20 without wear caused on either of them. For this end, polymer material, such as plastic or rubber is particularly suitable choice for the material of the collar 20. However, for making the contact between the rope 3,3′,3″,3′″ and the collar 20 even more gentle, it is preferable that the friction between the collar 20 and the 3,3′,3″,3′″ is designed to be low. Thereby, risks of rope damage can be further reduced. Low friction additionally reduces resistance caused by the collar 20, which is also advantageous, because thereby the unwinding is fluent and unvolatile. Low friction is particularly advantageous for achieving fluent and unvolatile unwinding when the rope 3,3′,3″,3′″ has a high-friction surface coating, such as a coating made of elastomer. This is because with high-friction coating the rope 3,3′,3″,3′″ could grip the collar 20 such that it momentarily stops, which would cause pulsation and disturb the unwinding. The low friction can be provided by choosing the material of the collar to be low-friction material. Then, plastic is particularly suitable choice for the material of the collar 20.
Low friction adequate for most cases can be provided by Polyethylene. The friction can minimalized with Polytetrafluoroethylene (PTFE), also known as Teflon™. There are of course numerous other known plastics commercially available that can be used as an alternative to the ones mentioned.
The rope is preferably a belt-like rope. Thereby, the rope 3,3′,3″,3′″ has width substantially larger than thickness thereof in transverse direction of the rope 3,3′,3″,3′″. Then, the rope 3,3′,3″,3′″ is wound in said spiral form by bending it around an axis extending in width-direction of the rope 3,3′,3″,3′″. Thus, the rope 3,3′,3″,3′″ settles easily in the spiral form. Due to the belt-like construction, the rope also resists bending towards axial direction of the rope reel 2,9, whereby it maintains well its spiral reel configuration and is not prone to unwind accidentally. When the belt is wound in the defined way, formation of twist within the rope reel or during unwinding can also be easily avoided, which is essential for a belt-like rope.
In general, it is preferable that the rope is under bending tension when wound in the spiral form. In this case, the defined configuration is particularly preferable because the rope can be unwound starting from the innermost rope rounds. The rope 3,3′,3″,3′″ can be unwound so that each round of the rope 3,3′,3″,3′″ still unwound and remaining on the rope reel 2,9 stays tensioned against the next outer round, the outermost round staying tensioned against said support member(s) 6, 6′. Thus, the bending tension cannot cause the rope end E to break away such that the unwinding starts to self-progress in an uncontrolled manner. As will be later explained, it is preferable that the rope 3,3′,3″,3′″ is, more specifically, a rod having a straight form when in rest state and elastically bendable away from the straight form, the rope 3,3′,3″,3′″ being under substantial bending tension in said spiral form. In rest state no external force is exerted on the rope 3,3′,3″,3′″, whereby the rope 3,3′,3″,3′″ as specified returns back to its original form after being bent owing to tension produced in the rope 3,3′,3″,3′″ in said bending.
In
The rope reel 2,9 is in the illustrated embodiments formed by the rope 3,3′,3″,3′″ wound in a two-dimensional spiral form, so substantially all the rope rounds are on the same plane. This is advantageous as in this way such tension in the rope reel, which tries to twist the rope in a manner difficult to control, can be minimized. Alternatively, the rope reel 2,9 can be formed by the rope 3,3′,3″,3′″ wound in a three-dimensional spiral form whereby substantially all the rope rounds are not on a same plane and the rope rounds pass in a slight angle relative to radial plane of the rope reel back and forth in axial direction as it is commonly known in the field of winding rope reels or corresponding reels.
Preferred alternatives for the cross section of the rope 3,3′,3″,3′″ are presented in
As for the material, the rope 3,3′,3″,3′″ is furthermore preferably such that the load bearing members 8, 8′, 8″, 8′″ thereof are made of composite material comprising reinforcing fibers f in polymer matrix m. This kind of rope when wound in spiral form is normally under substantial bending tension. Accordingly, handling the end E of the rope is challenging. Thereby, with the rope storage unit 1,1′ challenges appearing with this kind of ropes can be alleviated particularly efficiently.
Preferably, the reinforcing fibers f are carbon fibers. Thus a light rope with high tensile stiffness can be obtained, which makes it well suitable for elevator use. Said load bearing member(s) 8, 8′, 8″, 8′″ is/are parallel with the length direction of the rope. Said load bearing member(s) 8, 8′, 8″, 8′″ as well as the reinforcing fibers f are preferably parallel with the length direction of the rope so the tensile stiffness can be maximized. The rope produced by this kind of structure is indeed stiff under longitudinal tension, but as a side effect, it is also rigid under bending. In particular, it is a rod having a straight form when in rest state, and it is elastically bendable away from the straight form. Owing to the elasticity of the bending, the rope self-reverses back to straight form from bent form after the external forces are released. Due to the rigidity and elasticity of the behavior in bending, handling the end E of the rope of this type is particularly challenging. Thus, improvements provided by the rope storage unit 1,1′ are of particular importance.
It is preferable that each of said load bearing member(s) 8, 8′, 8″, 8′″ has width w,w′,w″,w′″ larger than thickness t,t′,t″,t′″ thereof as measured in width-direction of the rope 3,3′,3″,3′″, as illustrated. In this way a large cross-sectional area for the load bearing member/parts 3,3′,3″,3′″ is achieved, without weakening the bending capacity around an axis extending in the width direction of the rope 3,3′,3″,3′″. A small number of wide load bearing members comprised in the rope leads to efficient utilization of the width of the rope, thus making it possible to keep the rope width of the rope in advantageous limits.
Each rope 3, 3′ as illustrated in
The load bearing members 8′,8″,8″ of each rope presented in
As mentioned, the rope 3,3′,3″,3″′ is belt-shaped, particularly having two wide sides opposite each other. The width/thickness ratio of the rope is preferably at least at least 4, more preferably at least 5 or more, even more preferably at least 6. In this way a large cross-sectional area for the rope is achieved, the bending capacity around the width-directional axis being good also with rigid materials of the load bearing member. Thereby, the rope 3,3′,3″,3′″ suits well to be positioned in the rope support body 4 in bent form, as well as be used for suspending an elevator car.
The rope 3,3′,3″,3′″ is furthermore such that the aforementioned load bearing member 8 or the plurality of load bearing members 8′, 8″, 8′″ comprised in the rope 3,3′,3″,3′″ together cover majority, preferably 70% or over, more preferably 75% or over, most preferably 80% or over, most preferably 85% or over, of the width of the cross-section of the rope 3,3′,3″,3′″ for essentially the whole length of the rope 3,3′,3″,3′″. Thus the supporting capacity of the rope with respect to its total lateral dimensions is good, and the rope 3,3′,3″,3′″ does not need to be formed to be thick. This can be simply implemented with the composite as specified elsewhere in the application and this is particularly advantageous from the standpoint of, among other things, service life and bending rigidity in elevator use. The width of the rope 3,3′,3″,3′″ is thus also minimized by utilizing their width efficiently with wide load bearing member and using composite material. Individual belt-like ropes and the bundle they form can in this way be formed compact.
The inner structure of the load bearing member 8, 8′,8″,8′″ is more specifically as illustrated in
If, however, it is desired to reduce their random occurrence, the individual reinforcing fibers f can be pre-coated such that a polymer coating is around them already before the binding of individual reinforcing fibers to each other. In the invention the individual reinforcing fibers of the load bearing member can comprise material of the polymer matrix around them such that the polymer matrix m is immediately against the reinforcing fiber but alternatively a thin coating, e.g. a primer arranged on the surface of the reinforcing fiber in the manufacturing phase to improve chemical adhesion to the matrix m material, can be in between. Individual reinforcing fibers are distributed evenly in the load bearing member 8, 8′,8″,8′″ such that the gaps of individual reinforcing fibers f are filled with the polymer of the matrix m. The matrix m of the load bearing member 8, 8′,8″,8′″ is most preferably hard in its material properties.
A hard matrix m helps to support the reinforcing fibers f, especially when the rope bends, preventing buckling of the reinforcing fibers f of the bent rope, because the hard material supports the fibers f. To reduce the buckling and to facilitate a small bending radius of the rope, among other things, it is therefore preferred that the polymer matrix m is hard, and therefore preferably something other than an elastomer (an example of an elastomer: rubber) or something else that behaves very elastically or gives way. However, it is not necessary that the polymer matrix is of non-elastomer, e.g. if the downsides of this kind of material are deemed acceptable or irrelevant for the intended use. The most preferred materials for the matrix m are epoxy resin, polyester, phenolic plastic or vinyl ester. The polymer matrix m is preferably so hard that its module of elasticity (E) is over 2 GPa, most preferably over 2.5 GPa. In this case the module of elasticity (E) is preferably in the range 2.5-10 GPa, most preferably in the range 2.5-3.5 GPa. Preferably over 50% of the surface area of the cross-section of the load bearing member is of the aforementioned reinforcing fiber, preferably such that 50%-80% is of the aforementioned reinforcing fiber, more preferably such that 55%-70% is of the aforementioned reinforcing fiber, and essentially all the remaining surface area is of polymer matrix m. Most preferably such that approx. 60% of the surface area is of reinforcing fiber and approx. 40% is of matrix m material (preferably epoxy). In this way a good longitudinal strength of the rope is achieved.
As elsewhere explained, the rope 3,3′,3″,3′″ is wound in a spiral form with several rope rounds, including at least an radially outermost rope round, and a radially innermost rope round, and in said unwinding the rope is unwound round by round starting from the innermost rope round. As elsewhere explained, the rope reel 2,9 contained in the rope storage unit 1,1′ delimits a central space C inside the rope reel 2,9, the rope 3,3′,3″,3′″ having an end E protruding from the inner rim of the rope reel 2,9. As shown in
The guidance of the rope away from the central space is fluent, despite changes in diameter of the reel 2,9, when the opening 21 is smaller than the central space C as measured in radial direction of the reel 2,9, as shown in
The belt-like ropes as illustrated, have smooth surfaces. However, the ropes could be formed to have a contoured outer surface such as polyvee shapes or teeth. Even though the embodiments are most advantageous with belt-like ropes, many of the advantages would be achieved with ropes having a round cross section as well.
In this application, the term load bearing member refers to the part that is elongated in the length direction of the rope extending unbroken throughout the length of the rope. The part is able to bear without breaking a significant part of the tensile load exerted on the rope in question in the length direction of the rope. The tensile load can be transmitted inside the load bearing member all the way from its one end to the other.
As described above said reinforcing fibers f are carbon fibers. However, alternatively also other reinforcing fibers can be used. Especially, glass fibers are found to be suitable for elevator use, their advantage being that they are cheap and have good availability although a mediocre tensile stiffness and weight.
The rope storage unit and the method presented in the application is especially advantageous when the rope is a composite rope as presented. However, many of the advantages are achieved also with other kinds of ropes.
The feature that the rope is a rod having a straight form when in rest state and elastically bendable away from the straight form means that a 1.0 meter length of the straight rope 3,3′,3″,3′″ straightens back, when released after a bending from straight form to a curved form, in which bending the rope 3,3′,3″,3′″ is bent along its complete length to a curved form with a radius within the range of 0.3-0.5 meter. Thereby, the feature can be tested for example by bending the rope in this way
It is to be understood that the above description and the accompanying Figures are only intended to teach the best way known to the inventors to make and use the invention. It will be apparent to a person skilled in the art that the inventive concept can be implemented in various ways. The above-described embodiments of the invention may thus be modified or varied, without departing from the invention, as appreciated by those skilled in the art in light of the above teachings. It is therefore to be understood that the invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.
Number | Date | Country | Kind |
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14198544.0 | Dec 2014 | EP | regional |