Patent Application
20210130131
This application claims priority to European Patent Application No. 19206410.3 filed on Oct. 31, 2019, the entire contents of which are incorporated herein by reference.
The present invention relates to a method for roping an elevator as defined in the preamble of claim 1.
New rope materials and new suspension techniques have enabled new technical solutions and construction concepts in elevator design. That has brought a need to develop new working methods for assembling modern elevators. Roping an elevator is no longer a simple task since the amount of parallel ropes, rope types and suspension techniques affect the roping process. Often, the difficulty of roping an elevator is to achieve an equal tightness to all the parallel hoisting ropes. The hoisting ropes tend to stretch or elongate when they are newly loaded, and this can cause different tightness on the ropes. Additionally, the high friction of e.g. polyurethane (PU) ropes makes trimming the tightness during the assembly difficult because the PU ropes do not slip on the machinery traction sheave or rope pulleys. Therefore, planning the roping process accurately benefits in less labour, time, accidents, unnecessary work, rope jamming and rope damages.
Development of elevators has led to more complex suspension techniques. The 2:1 suspension demands twice as long ropes as 1:1 suspension, which makes the roping a more complex task. This can lead to problems when installing the hoisting ropes. To add friction between the ropes and the machinery traction sheave the ropes can be coated with friction adding material, such as polyurethane, later PU.
One way of installing the hoisting ropes is to lift rope reels to the upper part of the elevator shaft by means of a suitable lifting device, after which the ropes are lowered to the bottom part of the shaft. The problem with such a solution is first of all to lift the heavy rope reels to the upper part of the high elevator shaft. Another problem is that the lowering of long and heavy ropes is difficult to control because the lower the ropes are, the more their weight affects the rope-lowering machinery. A failure while lowering the ropes can lead the ropes to fall down at high speeds, which can cause hazards and/or break the structures.
In a conventional roping method free rope loops are lowered in the shaft onto top of the counterweight and the ropes are placed into the counterweight's diverting pulley grooves and after that the ropes are tightened and fixed to their terminals.
Disadvantages of the above-mentioned solution are inter alia that the rope loop may twist or get stuck behind some sharp object, e.g. rail brackets. PU coated ropes can easily be damaged in these kinds of cases and the elevator has to be roped again. This means significant additional working time and expensive material loss. Another disadvantage is that in the conventional method the parallel hoisting ropes can be left in uneven tightness and it does not take the rope elongation into account when the hoisting ropes are newly loaded.
It is an object of the present invention to eliminate the aforementioned drawbacks and to provide a simple, safe, effective and inexpensive method for installing elevator hoisting ropes, which method is particularly well suited for elevators with low to medium hoisting heights. The process of the method is characterized by what is set forth in the characterizing part of claim 1. Other embodiments of the invention are characterized by what is stated in other patent claims.
A further object is to even out the tension of the hoisting ropes by keeping the bunch of ropes equally tight all the time. Newly installed ropes tend to elongate under load when they travel in pulley grooves. The present method for roping an elevator exploits the mass of the counterweight during the installation to stretch the hoisting ropes to their full length. This will result improved quality in roping.
Inventive embodiments are also disclosed in the specification of this application. The inventive content of the application may also be defined otherwise than as set forth in the claims below. The inventive content may also be formed by several separate inventions, especially if the invention is considered in the light of its expressions or implicit subtasks, or in terms of the benefits or groups of benefits achieved. In this case, some of the attributes contained in the patent claims below may be redundant for individual inventive ideas. Similarly, the various details presented in connection with each of the embodiments of the invention may also be used in other embodiments. In addition, it can be noted that at least some of the sub claims can be considered to be inventive as such, at least in appropriate situations.
A method for roping an elevator where the roping starts at the bottom part of the elevator shaft where the first ends of the hoisting ropes are taken from reels from the roof of the elevator car and lead through diverting pulleys, preferably under the car and pulled back up with the help of an installation means, such as, a rope or ropes, to the car roof so that the hoisting ropes make a loop, preferably under the car. The elevator car is then hoisted to the upper part of the shaft where the first ends of the hoisting ropes are routed through the machinery traction sheave and the counterweight diverting pulleys, which counterweight has also been hoisted to the upper part of the shaft. Then the first rope ends are fixed to the counterweight side rope terminals. After that the counterweight is lowered to the bottom part of the shaft and during descent the hoisting ropes are unwound from the reels through the whole roping system with the help of the mass of the counterweight. When the counterweight reaches the stopper means in the pit the rope length is essentially correct. Then the second ends of the ropes are fixed to the car side rope terminals and tightened to the correct tension. This roping method ensures equal tightness of all the hoisting ropes.
The roping method according to the invention benefits in less labour, time, accidents, unnecessary work, rope jamming and rope damages because it keeps the bunch of ropes equally tight all the time. The hoisting ropes are unwound directly from the reels into the roping system and no hanging loops or rope ends are established because the hoisting ropes are unwound from the reels corresponding to the controlled rope lowering process. This prevents jamming behind snag points and thus any coating damages or other damages. This also helps to get the ropes equally tight. So, this means significant working time reduction and improved quality.
An advantage of the method according to the invention is that the installation of the ropes is much faster than with the methods known in the art. One additional benefit is that the installation is not physically demanding. A further advantage is that the method is simple and inexpensive.
The invention will now be described in more detail with reference to the accompanying drawings, in which:
Preferably, the elevator car pulleys 10 are placed at the bottom part of the elevator car 2 and the counterweight pulleys 11 are placed at the top part of the counterweight 3.
At the bottom part of the elevator shaft 1, the first end of the hoisting rope 4 is lowered from the reels 4a at the top of the car 2 on the side of the car side rope terminal 6 to the pit of the shaft 1. The installation means 12 is lowered from the other side of the car from the elevator 2 roof to the pit. Then the hoisting rope 4 is routed through the car pulleys 10. With the help of the installation means 12 the hoisting rope 4 is then pulled up to the elevator car 2 roof and fastened there to some fastening member, which is a part of the car 2 or attached to the car 2, for example the roof balustrade.
For the sake of clarity, only one hoisting rope 4 is mentioned here. However, the elevator can comprise also more than one hoisting ropes 4 and when one hoisting rope is mentioned all the hoisting ropes are meant. Similarly, when only one reel 4a is mentioned it means that there can be more than one parallel reels 4a, one for each hoisting rope 4.
In this phase of the method the elevator car 2 is hoisted to the upper part of the elevator shaft 1 with the help of the auxiliary hoist 8 and its rope 9, which auxiliary hoist 8 is placed above the elevator car 2. After hoisting the elevator car 2 it is parked and secured at the upper part of the elevator shaft 1 with safety members, parking chains and/or corresponding securing means, which are not shown in the figure. Also, the counterweight 3 has been hoisted up to the upper part of the elevator shaft 1 with the help of preferably the same auxiliary hoist 8 and its rope 9. When hoisting the counterweight 3 with the auxiliary hoist 8 the rope 9 is routed over the auxiliary diverting pulley 13, which is suitably fitted above the counterweight 3.
At the upper part of the elevator shaft 1 the first end of the hoisting rope 4 is uncoupled from the fastening member, to which it was fastened at the bottom part of the elevator shaft 1. Then the hoisting rope 4 is routed over the machinery traction sheave 5 and under the counterweight pulleys 11. Then the first end of the hoisting rope 4 is fixed to the counterweight side rope terminal 7 at the counterweight side of the shaft.
In the next phase or the final phase of the method the counterweight 3 is lowered towards the pit until it reaches the pre-set stopper means in the bottom part of the elevator shaft 1. The stopper means is not shown in the figures. During the lowering of the counterweight 3, the hoisting ropes 4 are unwound from the reels 4a through the whole roping system and the mass of the counterweight 3 stretches the hoisting ropes 4 to their full length. The stopper means is placed in the pit at such a height that after the lowering when the counterweight 3 is stopped by the stopper means the hoisting ropes 4 have at the same time been elongated to their normal length of use. Thus, when the counterweight 3 reaches the stopper means the rope length is at the same time essentially correct. The second ends of the hoisting ropes 4 are fixed to the car side rope terminal 6 and tightened to the correct and wanted tension. The counterweight 3 is lowered with the help of the auxiliary hoist 8.
It is obvious to the person skilled in the art that the invention is not restricted to the examples described above but that it may be varied within the scope of the claims presented below. Thus, for instance the method can comprise also different phases than those described above.
It is also obvious to the person skilled in the art that the method according to the invention can be used also in different kind of elevators than the elevator described above.
It is also obvious to the person skilled in the art that the diverting pulleys in the elevator car can be at the top part of the elevator car and the diverting pulleys in the counterweight can be at the lower part of the counterweight.
It is also obvious to the person skilled in the art that there can be more than one installation means or some other method can be used to lift the hoisting ropes to the car roof than using an installation means, such as a rope or ropes.
It is also obvious to the person skilled in the art that the counterweight is not necessarily in its final weight in the installation phase. For example, just part of the weight is installed in the installation phase and the rest is added later.
It is also obvious to the person skilled in the art that the auxiliary hoist can also be placed on top of the counterweight instead of on top of the elevator car. In this case, the auxiliary diverting pulley is placed on top of the elevator car. In this way the auxiliary diverting pulley is used to align the auxiliary hoisting rope to a correct line with the object to be hoisted.
| Number | Date | Country | Kind |
|---|---|---|---|
| 19206410.3 | Oct 2019 | EP | regional |
