Suspension arrangement and guide shoe arrangement for an elevator

A suspension arrangement and guide shoe arrangement of an elevator, which arrangement comprises at least an elevator car and at least two compensating weights, which are for their part connected to support the elevator car by the aid of at least two suspension members, such as by the aid of ropes or belts, and also by the aid of diverting pulleys, and a hoisting machine provided with at least one traction sheave or corresponding, as well as at least two traction members, such as belts, ropes or chains, separate from the suspension members, which traction members are configured to transmit the rotational movement of the traction sheave into movement of the elevator car and of the compensating weights. There are at least four guide rails of the elevator car and they are fitted into an elevator hoistway symmetrically to each other in relation to the elevator car.

The object of the invention is a suspension arrangement and guide shoe arrangement for an elevator.

In the suspension arrangement and guide shoe arrangement according to the invention the hoisting machine of the elevator is in the bottom part of the elevator hoistway and the suspension and traction of the elevator car are separated from each other. In this case the suspension members of the elevator car, such as the suspension ropes or suspension belts, and the traction members of the elevator car are separate from each other. This type of solution is well suited to buildings of different heights and even to elevators intended for extremely tall buildings, in which one problem is that when the location of the hoisting machine of the elevator is above, installation of the hoisting machine and peripheral structures of the elevator is awkward, expensive and even dangerous. The arrangement according to the invention is also suited to new elevators in low-rise buildings that previously had no elevator. In addition, the solution according to the invention is well suited to the modernization of old elevators.

Elevator solutions wherein the hoisting machine of the elevator is disposed on the base of the elevator hoistway, or close to the bottom part of the elevator hoistway, are known in the art. When the hoisting machine is disposed thus, the suspension ropes of the elevator cannot generally function simultaneously as the means intended for moving the elevator car, but instead separate traction ropes, traction belts or some other traction members are needed for moving the elevator car. One such prior-art solution is presented in international patent publication no. WO03/043927 A2, in which, inter alia, FIGS. 8 and 9 present suspension solutions wherein the hoisting machine of an elevator is disposed in the bottom part of the hoistway and the suspension ropes and traction ropes of the elevator car are different ropes. The elevator car and the counterweight are supported by the aid of a diverting pulley above, over which the suspension ropes fixed to the elevator car and to the counterweight pass around. Correspondingly, the moving of the elevator car is implemented with a separate toothed belt, which passes around the traction sheave of a hoisting machine below and is fixed from below between the elevator car and the counterweight. A problem in this solution is at least that the suspension of the elevator car is not in balance in relation to the center point of the elevator car. In this case additional stresses are exerted on the guide rails, support members and other hoistway structures, owing to which they must e.g. be dimensioned to be unnecessarily large. Additional stresses are produced e.g. when the load of the elevator car is not evenly distributed inside the elevator car. Another problem is that the solution is difficult to alter in relation to the layout, because one large counterweight takes so much hoistway space that flexible layouts cannot easily be used.

The aim of the present invention is to eliminate the aforementioned drawbacks and to achieve an inexpensive and easy-to-implement suspension arrangement and guide shoe arrangement, which combines the advantages of a hoisting machine disposed in the bottom part of the elevator hoistway and of flexible layout design, and which enables a type of new layout for an elevator with traction from below, by the aid of which layout the balance, producibility and space efficiency of the elevator can be improved. Another aim is to achieve a suspension arrangement and guide shoe arrangement of an elevator, which owing to its better balancing enables lighter and cheaper hoistway structures that have a longer life.

Some inventive embodiments are also discussed in the descriptive section of the present application. The inventive content of the application can also be defined differently than in the claims presented below. The inventive content may also consist of several separate inventions, especially if the invention is considered in the light of expressions or implicit sub-tasks or from the point of view of advantages or categories of advantages achieved. In this case, some of the attributes contained in the claims below may be superfluous from the point of view of separate inventive concepts. Likewise the different details presented in connection with each embodiment can also be applied in other embodiments. In addition it can be stated that at least some of the subordinate claims can, in at least some situations, be deemed to be inventive in their own right.

One advantage, among others, of the solution according to the invention is that by means of it symmetrical suspension, traction and also guidance of the vertical movement of the elevator car and compensating weights are made possible in an elevator in which the suspension ropes are separated from the traction members. In this case it is easy to keep the elevator car in balance all the time, in which case additional stresses are not exerted on the hoistway structures. The invention enables the use of two or more compensating weights, which can be smaller in size than one large counterweight or compensating weight. An advantage of small compensating weights is also that the solution according to the invention is space-efficient in both the width direction and the depth direction of the elevator hoistway. Yet another advantage is that by means of the arrangement according to the invention the rope arrangements and layouts of elevators can be diversified, which enables easier layout design. Another advantage is that owing to the smaller stresses the hoistway structures can be lighter and cheaper than in prior-art solutions. Another advantage is also that disposal of the traction members on both sides of the motor shaft of the hoisting machine balances the forces on the shaft better than in prior-art solutions. Another advantage is that all the diverting pulleys in the bottom part of the elevator hoistway can be disposed on almost the same plane in the vertical direction, in which case the machine structure is very shallow.

Another advantage is also the modularized machine structure. In this case from the viewpoint of production, three modules can be created, of which the motor module is always placed in the center of the hoistway, and extension modules provided with diverting pulleys are suitably disposed on both sides of it according to the size of the hoistway, and the extension modules are fixed into their position e.g. on the bottom ends of the guide rails. Another advantage is that when the traction is on the width center line of the hoistway, the bottom safety space can be made to fit in front of the motor module opposite the motor in the depth direction of the hoistway. One advantage is also that the guide rail forces are divided between four guide rails, instead of two, in which case smaller and cheaper guide rails can be used. Yet another advantage is that the whole solution is, owing to its symmetry, easily convertible to suit different hoistway sizes, in which case finding solutions viable for production is easier.

One inventive aspect in connection with the invention is guiding the elevator car and the compensating weight—or counterweight—on shared guide rails. In other words, the tracks of the elevator car and compensating weight/counterweight are determined with guide rails, at least one guide rail, preferably more, of which is common to both the elevator car and to the compensating weight/counterweight. In this way material savings and savings in installation work are achieved.

One advantageous manifestation of the invention is that the counterweight and/or elevator car is fixed to a traction member and/or to a suspension member at two fixing points that are between the guide shoes corresponding to the guide rails. The symmetrical placement of a fixing point between the guide rails results in smaller guide shoe forces.

To enable the arrangement according to the invention, the elevator arrangement comprises at least an elevator car1configured to move up and down in an elevator hoistway and at least one or more compensating weights3a,3b, which are for their part connected to support the elevator car by the aid of suspension members4a,4b, such as belts or ropes, and also by the aid of e.g. diverting pulleys5a,5bmounted on bearings in the top part of the elevator hoistway. In addition, the arrangement according to the invention comprises a hoisting machine9, provided with at least one traction sheave8or corresponding and disposed in the bottom part of the elevator hoistway, and at least two or more traction members14a,14b, such as ropes or belts, that are fully separate from the suspension members4a,4b, which traction members are configured to transmit the rotational movement of the traction sheave8into linear movement of the elevator car1and of the compensating weights3a,3b. Characteristic to the solution according to the invention, and common to all the different embodiments of the invention, is that each compensating weight3a,3b, or in some cases more than two compensating weights, is connected, by the aid of its own traction member14a,14bprovided with e.g. essentially spring tensioning or constant-force tensioning, to most preferably one and the same hoisting machine9.

FIG. 1presents a simplified and diagrammatic side view of one elevator arrangement applicable to the solution according to the invention. The elevator arrangement according toFIG. 1comprises two compensating weights3aand3bfunctioning as counterweights and disposed symmetrically on different sides of the elevator car1, both of which compensating weights are connected by means of suspension members4aand4bto a car sling2fitted around the elevator car1. One suspension member4a,4bcan be e.g. just an individual rope, belt or chain, or it can be composed of a number of parallel members, e.g. hoisting ropes. The suspension members4a,4bare e.g. steel wire ropes or belts and they are fixed at their first ends to the top part of the compensating weights3aand3b, from where they are led upwards to pass around the top of the diverting pulleys5aand5bfitted in the top part of the elevator hoistway, from where onwards down to the fixing means6aand6bon the top part of the car sling2, to which fixing means the suspension members4a,4bare fixed at their second ends.

A motor module7is fitted in the bottom part of the elevator hoistway, which motor module comprises at least a hoisting machine9arranged to move the elevator car1and provided with a traction sheave8, as well as two diverting pulleys10aand10b. The arrangement also comprises two extension modules11aand11b, which are fitted at the edges of the elevator hoistway on opposite sides of the motor module7to each other. Both extension modules comprise at least two diverting pulleys, which are arranged to guide the traction members14aand14b.

The first traction member14ais fixed at its first end to the bottom part of the first compensating weight3a, from where it is led down to pass around the bottom of the first diverting pulley12aof the first extension module11a, from where onwards under the first diverting pulley10aof the motor module7, after which over the traction sheave8. From the traction sheave8the first traction member14ais led to pass around the bottom of the second diverting pulley10bof the motor module7, from where onwards under the second diverting pulley13bof the second extension module11b, after passing around the bottom of which diverting pulley13bthe traction member14ais led up to the car sling2, to the bottom part of which the first traction member14ais fixed e.g. via a fixing means provided with e.g. spring tensioning or constant-force tensioning.

The second traction member14bis, for its part, fixed at its first end to the bottom part of the second compensating weight3b, from where it is led down to pass around the bottom of the first diverting pulley12bof the second extension module11b, from where onwards over the second diverting pulley10bof the motor module7, after which under the traction sheave8. From the traction sheave8the second traction member14bis led to pass around the top of the first diverting pulley13aof the motor module7, from where onwards under the second diverting pulley13aof the first extension module11a, after passing around the bottom of which diverting pulley13athe traction member14bis led up to the car sling2, to the bottom part of which the second traction member14bis fixed e.g. via a fixing means provided with e.g. spring tensioning or constant-force tensioning.

In the situation according toFIG. 1, the traction sheave8rotates in the direction of the arrows drawn above and below the traction sheave, in which case the elevator car1moves downwards and the compensating weights3aand3bmove upwards.

FIG. 2presents a simplified and diagrammatic top view of an elevator arrangement according toFIG. 1. The elevator car1is fitted inside the car sling2. Essentially vertical guide rails17are fixed by the aid of clamps16to the side walls of the elevator hoistway15, guided by which guide rails the elevator car1is arranged to travel up and own in the hoistway15. On both sides of the elevator car1are two guide rails17that are essentially similar to each other and are fitted symmetrically with respect to each other and to the elevator car1. In this case the guide rails17are disposed symmetrically as viewed from above in relation both to the depth center line1aof the elevator car running through the center point of the elevator car1and to the width center line1bof the elevator car running through the center point of the elevator car1.

Compensating weights3a,3bare fitted between the guide rails17on both sides of the elevator car1, at least one compensating weight each side of the elevator car1, which compensating weights3a,3bare configured to travel in the hoistway15resting on the first outer surfaces, which are opposite each other, of the guide rails17. InFIG. 2the compensating weights3a,3bare, however, for the sake of clarity presented as slightly detached from the aforementioned outer surfaces, which are opposite to each other, of the guide rails17. Correspondingly the elevator car1is configured to rest, by the aid of roller guide shoes18fixed to the car sling2, on the second outer surfaces of the guide rails17, which surfaces point away from each other.

The suspension members4a,4bof the elevator car1are arranged to be fixed at their first ends to the top parts of the compensating weights3a,3band at their second ends to the fixing means6a,6bon the car sling2. The fixing points of the suspension members4a,4bare marked in the figure with the number19. As is seen fromFIG. 2, the suspension and the guidance of the vertical movement of the elevator car1is implemented symmetrically with respect to the center lines1aand1b, in which case no additional stresses or strains are exerted e.g. on the guide rails17and other hoistway structures.

FIG. 3presents a simplified and diagrammatic top view of the top part of the elevator hoistway15. Diverting pulleys5aand5bare fitted in the top part of the elevator hoistway15on opposite sides of the elevator car1in the lateral direction. In this embodiment on the first side of the elevator car1above the elevator car1and on the side of the travel profile of the elevator car1are two first diverting pulleys5asymmetrically on different sides of the depth center line1aof the elevator car. Correspondingly, on the second side of the elevator car1above the elevator car1and on the side of the travel profile of the elevator car1are two second diverting pulleys5bsymmetrically on different sides of the depth center line1aof the elevator car1. In addition the diverting pulleys5aand5bare disposed symmetrically to each other in relation to the width center line1bof the elevator car1. The suspension members4a,4bof the elevator car1are led over the diverting pulleys5a,5bfrom the compensating weights3a,3bto the elevator car1, as is already described in the descriptive part ofFIG. 1.

FIG. 4presents an oblique view from the side and top of a suspension arrangement of the compensating weights of the elevator arrangement presented above.FIG. 4presents only the first compensating weight3a, because the second compensating weight3bis suspended in the same way. In the situation according toFIG. 1, the elevator car1is in its bottom position and the compensating weights3aand3bare in their top position near the diverting pulleys5aand5b. The first suspension members4a, which are thus at least two belts, ropes or two pluralities of parallel ropes, leaving from the compensating weight3aeach pass around the top of their own diverting pulley5aand then descend to their fixing points19on the elevator car1. The suspension members4bon the second side of the elevator car1are suspended in a corresponding manner.

FIG. 5presents a simplified and diagrammatic top view of the bottom part of the elevator hoistway15. For the sake of clarity, inFIG. 5the diverting pulleys in the bottom part of the hoistway are not presented, and the traction members14aand14bare presented as cross-sections. The traction members14aand14bare preferably e.g. toothed belts, which are configured to travel a part of the distance parallel with each other and symmetrically to each other on both sides of the depth center line1aof the elevator car1. In the arrangement according toFIG. 5the traction member14ais disposed on a first side of the depth center line1aof the elevator car1and the traction member14bis disposed on a second side of the depth center line1aof the elevator car1. In addition, the horizontal distances of the traction members14aand14bare symmetrically disposed from the width center line1bof the elevator car1.

The toothed contact surface of the traction sheave8is so wide that both the traction members14a,14bfit side-by-side onto the contact surface of the traction sheave8without interfering with each other. In this way one and the same hoisting machine9and also one and the same traction sheave8give to both the traction members14a,14ba force producing linear movement of the elevator car1and of the compensating weights3a,3b.

FIG. 6presents a simplified, magnified and diagrammatic top view of the guide rail structures and guide shoe structures of an elevator arrangement according toFIG. 1, the structure and operation of which have been described already in conjunction withFIG. 2. For the sake of clarity, inFIG. 6the clamps16are presented slightly detached from the side wall of the elevator hoistway15, although in reality they are attached to the side wall. The guide rail17of the elevator car1is in its cross-section essentially a U-shaped beam, which opens towards the elevator car1. In this case it has been possible to fit the fixing means6a,6bof the suspension members4a,4bon the car sling2, and the fixing points19of the suspension members4a,4bin them, inside the web of the guide rail17, in which case it has been possible to utilize the space in the width direction of the elevator hoistway15better. The compensating weights3aand3bdisposed between the guide rails17are configured to travel in the hoistway15resting on the first outer surfaces, which are opposite each other, of the web of the guide rails17. For the sake of clarity, the compensating weight3ais presented inFIG. 6slightly detached from the aforementioned outer surface of the guide rails17. Correspondingly the elevator car1is configured to rest, by the aid of roller guide shoes18fixed to the car sling2, on the second outer surfaces of the guide rails17, which surfaces point away from each other.

Flanges, turned outwards from the web of the guide rail at a right angle with respect to the web of the guide rail17, are additionally on the guide rail17on the side of the elevator car1, of which the flanges17athat point towards each other are configured as a fixing surface for an enclosure board20, with which the compensating weight3a,3bis enclosed in its own enclosure. Good enclosing reduces the noise disturbance when, inter alia, the elevator car1and the compensating weights3a,3bmeet each other in the elevator hoistway.

It is further characteristic to the arrangement according to the invention that the positioning point of the diverting pulleys5a,5bdisposed in the top clearance of the elevator hoistway15is configured such that the elevator car1can rise past the diverting pulleys5a,5bin the top end of the elevator hoistway15right to the top end of the elevator hoistway15. In this way the most space-efficient layout solution possible is also achieved in the top end of the elevator hoistway15.

It is obvious to the person skilled in the art that the invention is not limited solely to the examples described above, but that it may be varied within the scope of the claims presented below. Thus, for example, the suspension solutions can also be different to what is presented above.

It is further obvious to the person skilled in the art that the location of the hoisting machine can be elsewhere than what is presented above. The hoisting machine can be on the base of the elevator hoistway, or close to the base, but also on some side of the elevator hoistway and also in the top part of the elevator hoistway.

It is also obvious to the person skilled in the art that the number of compensating weights can also be greater than two. There can be e.g. three, four, six, eight, ten or even more compensating weights disposed in a different manner.