HK1081936B - Elevator without counterweight and method for forming an elevator without counterweight - Google Patents

Description

Elevator without counterweight and forming method thereof

Technical Field

The invention relates to an elevator without counterweight and to a method of forming an elevator.

Background

One of the objectives in elevator development work is to achieve efficient and economical utilization of building space. In recent years, this development work has produced, among other things, a wide variety of elevator solutions without machine room. Good examples of elevators without machine room are disclosed in specifications EP0631967(a1) and EP 0631968. The elevators described in these specifications are fairly efficient in respect of space utilization as they have made it possible to eliminate the space required for the elevator machine room without the need to enlarge the elevator shaft. In the elevators disclosed in these specifications the machine is compact at least in one direction, but in other directions it may have much larger dimensions than a normal elevator machine.

In these basically good elevator solutions, the space required for the hoisting means limits the freedom of choice of elevator arrangement solutions. Space is required for the various arrangements required for the passage of the hoisting ropes. It is difficult to reduce the space required for the elevator car itself on its track and likewise the space required for the counterweight, at least at a reasonable cost and without impairing elevator performance and operational quality. In a traction sheave elevator without machine room, it is often difficult to mount the hoisting machine in the elevator shaft, especially in a solution with machine above, since the hoisting machine is a large object with a considerable weight. Especially in the case of larger loads, speeds and/or hoisting heights, the size and weight of the machine are problems related to the installation, even though the required size and weight of the machine have in practice limited the sphere of application of the concept of elevator without machine room or at least prevented the introduction of said concept in larger elevators. The space available in the elevator shaft in the modernization of the elevator often limits the scope of application of the concept of elevator without machine room. In many cases, especially when the hydraulic elevator has to be modernized or replaced, the concept of using a roped elevator without machine room is not practical due to insufficient space in the shaft, especially in cases where there is no counterweight in the solution of the hydraulic elevator to be modernized/replaced. A disadvantage of elevators provided with a counterweight is the cost of the counterweight and the space required in the shaft. Roller elevators, which are currently rarely used, have the drawbacks of: the hoisting device is heavy and complex, requiring large power/torque. Elevator solutions without counterweight are rare in the prior art and no suitable solution is known. Previously, it has not been technically or economically reasonable to make elevators without counterweight. One such solution is disclosed in specification WO 9806655. A recent elevator solution without counterweight is a feasible solution. In prior-art elevator solutions without counterweight the tensioning of the hoisting rope is implemented using a weight or spring, which is not an attractive solution for accomplishing the tensioning of the hoisting rope. Another problem with elevator solutions without counterweight when very long ropes are used, e.g. due to a large hoisting height or large rope length required for a high suspension ratio, is the compensation of the elongation of the ropes and the fact that the friction between the traction sheave and the hoisting ropes is insufficient for the operation of the elevator due to rope elongation. In hydraulic elevators, especially in hydraulic elevators with a lifting force exerted from below, the shaft efficiency, in other words the ratio of the shaft cross-sectional area occupied by the elevator car to the total cross-sectional area of the elevator shaft, is rather high. This is a significant factor in the traditional choice of hydraulic elevators as elevator solutions for a building. Hydraulic elevators, on the other hand, have a number of disadvantages related to their hoisting equipment and oil consumption. Hydraulic elevators consume a lot of energy, oil may leak from the elevator installation is an environmental risk, the required regular oil changes constitute a high cost, and even in well-installed elevators an unpleasant smell is generated as small amounts of oil escape into the elevator shaft or machine room and from there further into other parts of the building and into the environment etc. Due to the shaft efficiency of hydraulic elevators, retrofitting the elevator with another type of elevator instead of the one that avoids the drawbacks of hydraulic elevators, while necessarily involving the use of a smaller elevator car, is not an attractive solution for the owner of the elevator. In addition, the small machine space of the hydraulic elevator, which may be located far from the elevator shaft, makes it difficult to change the elevator type.

There are a large number of traction sheave elevators installed and already in use. Such traction sheave elevators were built at their time according to the user's needs as thought at that time and the intended use of the building in question. Since then, in many cases, the needs of the users and the use of the building have changed, and old traction sheave elevators may have proven to be insufficient in car size or other aspects. For example, older and relatively small elevators are necessarily unsuitable for transporting trolleys or wheelchairs. On the other hand, in older buildings that have been moved from home use to office or other use, the smaller elevators installed at the corresponding times are no longer sufficient in capacity. As is known, enlarging such a traction sheave elevator is practically impossible because the elevator car and the counterweight already take up the cross-sectional area of the elevator shaft without a rational way of enlarging the elevator car.

Disclosure of Invention

The object of the invention is generally to achieve at least one of the following objectives. In one aspect the object of the invention is to develop the elevator without machine room further so that it is possible to achieve more efficient space utilization in the building and elevator shaft than before. This means that the elevator must be designed such that it can be installed in a fairly narrow elevator shaft if necessary. One objective is to achieve an elevator in which the hoisting ropes have a good grip/contact on the traction sheave. Another objective is to achieve an elevator solution without counterweight without compromising the properties of the elevator. A further object is to eliminate the undesirable effects of rope elongation. One object of the invention is to create a method for replacing or modernizing a hydraulic elevator with/as a rope-driven elevator without reducing or at least without significantly reducing the size of the elevator car. It is an object of the invention to enable a rope-driven elevator to be modernized into an elevator with a significantly larger elevator car or to be replaced with an elevator with a larger elevator car than before.

The object of the invention should be achieved without compromising the possibility of changing the basic elevator arrangement.

According to one aspect of the invention an elevator without counterweight is provided, in which the elevator car is suspended by means of hoisting ropes consisting of a single rope or several parallel ropes, said elevator having a traction sheave which moves the elevator car by means of the hoisting ropes, characterized in that: the elevator has rope portions of hoisting ropes going upwards and downwards from the elevator car, and the rope portions going upwards from the elevator car are under a first rope tension, which is greater than a second rope tension, which is the rope tension of the rope portions going downwards from the elevator car, wherein the ratio of the rope tensions across the traction sheave is constant, and said elevator construction is used to replace an elevator installed in the elevator shaft or is constructed by making various modifications in this existing elevator.

Preferably, the existing elevator is a hydraulic lift elevator.

Preferably the existing elevator is a traction sheave elevator.

Preferably, the elevator car of the elevator has a floor area larger than that of existing elevators.

Preferably, the elevator has a compensating device.

Preferably, the compensation means is a lever, a set of tension pulleys or a compensation pulley.

Preferably the elevator has a compensating device and the compensating device comprises one or more diverting pulleys.

Preferably the continuous contact angle between the traction sheave and the hoisting ropes is at least 180 °.

Preferably, the hoisting ropes used are those having a mass of more than 2000N/mm₂The strength of (2) is high.

Preferably the hoisting ropes have a diameter smaller than 8 mm.

Preferably the diameter of the hoisting ropes is between 3-5 mm.

Preferably, the weight of the lifting device is much less than the load.

Preferably, the traction sheave is coated with polyurethane or rubber.

Preferably, the traction sheave, at least in the area of the rope grooves, is made of metal.

Preferably, the metal is cast iron.

Preferably, the traction sheave has concave rope grooves.

Preferably the D/D ratio of the diverting pulleys below the elevator car is below 40.

According to another aspect of the invention a method is provided for forming an elevator without counterweight instead of or by making various modifications in an existing elevator installed in an elevator shaft or equivalent, characterized in that: a hoisting function arrangement to replace the hoisting function of an existing elevator is installed, comprising a set of hoisting ropes, which set of hoisting ropes comprises one rope or a plurality of parallel ropes; and an apparatus for the elevator for driving the hoisting ropes, and the elevator car of the elevator to be formed is connected to the hoisting ropes in such a way that the elevator has rope portions going upwards and downwards from the elevator car, so thatAnd the elevator roping arrangement is provided with a compensating system for maintaining a substantially constant ratio (T) between the rope forces acting in the upward and downward direction₁/T₂)。

Preferably, the alternative lift function is mounted at the location of a hydraulic lift function.

Preferably the alternative hoisting function is mounted at a traction sheave operated hoisting function comprising a counterweight.

Preferably, the alternative lift function device is installed to replace a lift function device implemented using a drum or a screw.

Preferably the equipment comprised in the hoisting function device of the existing elevator is removed from the elevator shaft or equivalent.

Preferably a replacement elevator car of larger size than the existing elevator car is formed in the elevator shaft.

Embodiments of the invention are also discussed in the description part of the present application, and the content of the application can be determined in a different manner than in the claims. The inventive content may also consist of several separate inventions, especially if the invention is examined in the light of expressions or implicit sub-tasks or from the point of view of advantages or categories of advantages achieved. Thus, some of the attributes contained in the technical solutions may be superfluous from the point of view of separate inventive concepts. E.g. the equipment comprising the main parts of the elevator to be installed in place of the existing elevator, or the equipment designed for modernizing the hoisting system of the existing elevator, the equipment comprising the machine, ropes and diverting pulleys needed for the hoisting function and the auxiliary devices for installing them, and possibly also the elevator car and guide rails, are all an invention together with instructions for replacing and improving an elevator at least in respect of the hoisting function in order to make it consistent with this application.

By applying the invention, one or more of the following advantages may be obtained, among others.

Owing to a small traction sheave, an elevator and/or elevator machine of fairly compact dimensions is obtained;

good traction sheave grip, in particular by using double wrap roping, while the low weight of the components results in a significant reduction in the weight of the elevator car;

the compact machine size and the thin and substantially round ropes allow the elevator machine to be placed relatively freely in the shaft. The elevator solution of the invention can thus be implemented in a fairly wide variety of ways in both the case of elevators with machine above and in the case of elevators with machine below;

the elevator car can advantageously be placed between the elevator car and a shaft wall;

all or at least part of the weight of the elevator car is taken up by the elevator guide rails;

the application of the invention makes it possible to make effective use of the cross-sectional area of the shaft. Thus, for example, a hydraulic elevator can be modernized into a rope-driven elevator or replaced in the same shaft with a rope-driven elevator without reducing the size of the elevator car, or an old traction sheave elevator can be replaced or modernized into a larger elevator;

the light and thin ropes are easy to handle, allowing considerably faster installation;

for example, in elevators for nominal loads below 1000kg, the thin and strong steel ropes of the invention have a diameter of the order of only 3-5mm, although thinner and thicker ropes may also be used;

with a rope diameter of about 6mm or 8mm, a fairly large and fast elevator according to the invention can be obtained;

it is possible to use ropes, either coated or uncoated;

the use of a smaller traction sheave makes it possible to use a smaller elevator drive motor, which means a reduction in drive motor acquisition/manufacturing costs;

the invention can be used in gearless and geared elevator motor solutions;

although the invention is primarily intended for use in elevators without machine room, it can also be used in elevators with machine room;

in the invention, by increasing the contact angle between the hoisting ropes and the traction sheave, a better grip and a better contact between them is obtained;

the size and weight of the elevator car can be reduced due to the improved grip;

the space saving potential of the elevator of the invention is greatly increased, since the space required for the counterweight is at least partly reduced;

energy saving and at the same time cost saving results due to the lighter and smaller elevator systems;

the arrangement of the machine in the shaft can be chosen relatively freely, since the space required for the counterweight and counterweight guide rails for roping can be used for other purposes;

by mounting at least the elevator hoisting machine, the traction sheave and a pulley functioning as a diverting pulley in a complete unit, which unit is fitted as part of the elevator of the invention, considerable savings in installation time and costs will be achieved.

In the elevator solution of the invention it is possible to arrange all the ropes in the shaft on one side of the elevator car; for example, in the case of a rucksack solution, the ropes can be arranged to run behind the elevator car in the space between the elevator car and the rear wall of the elevator shaft;

the invention makes it easy to implement also in landscape-type elevator solutions;

since the elevator solution of the invention does not necessarily comprise a counterweight, it is possible to implement an elevator solution with elevator doors on several walls of the elevator car, in the extreme case even on all walls of the elevator car. In this case, the elevator car guide rails of the elevator are arranged at the corners of the elevator car;

the elevator solution of the invention can be implemented with several different machine solutions;

the suspension of the elevator car can be implemented using almost any suitable suspension ratio;

compensating rope elongations by means of a compensating system according to the invention is an inexpensive and simple practical method;

with the rope elongation compensating solution of the invention it is possible to obtain a force T acting on the traction sheave₁/T₂A constant ratio therebetween;

force T acting on the traction sheave₁/T₂The ratio therebetween is independent of the load;

by using the rope elongation compensating system of the invention, unnecessary stresses on the machine and the rope can be avoided;

by using the rope elongation compensating system of the invention, the force T₁/T₂The relationship between can be optimized to obtain the desired value;

the solution of the invention for compensating rope elongations is a safe solution making it possible to guarantee friction/contact between the traction sheave and the hoisting ropes in all situations;

furthermore, the rope elongation compensation solution of the invention makes it unnecessary to tension the hoisting ropes with more than necessary load to ensure friction between the traction sheave and the hoisting ropes, so that the service life of the hoisting ropes is increased and their vulnerability is reduced;

when compensating rope elongations with the arrangement according to the invention for compensating rope elongations with compensating pulleys having different diameters, it will be possible with this solution to compensate even large rope elongations depending on the diameters of the pulleys used;

by using the rope elongation compensating solution according to the invention, in which the compensating device used is a differential gear, even large rope elongations can be compensated, especially in situations where the hoisting height is high.

The main area of application of the invention is elevators designed for transporting people and/or freight. The general range of application of the invention is in elevators whose speed range is about 1.0m/s or below but may also be somewhat higher. An elevator with a traveling speed of 0.6m/s, for example, is easy to implement according to the invention.

In both passenger and freight elevators, many of the advantages achieved by means of the invention are profoundly shown even in elevators for only 2-4 persons and have been clearly shown in elevators for 6-8 persons (500-.

According to the invention, when an elevator, such as a hydraulic elevator or a traction sheave elevator, is to be renewed or replaced, the existing elevator is partially or completely removed to form a new elevator, in which the elevator car is suspended on a set of continuous hoisting ropes comprising rope portions going upwards from the elevator car and downwards from the elevator car. The new elevator to be installed is a traction sheave elevator, preferably made completely without counterweight. The original hoisting function is always no longer used and preferably also removed in practice, which means that e.g. in the case of a hydraulic elevator the hydraulic cylinder and the hydraulic machine are removed from the elevator or in the case of a traction sheave elevator the original hoisting ropes, hoisting equipment and counterweight are removed. The same elevator car, or an enlarged or new elevator car, is suspended on a new set of hoisting ropes, which can be installed at the same time as the original hoisting function is being cancelled or as a separate installation. A hydraulic elevator or a corresponding hydraulic elevator lifted from below can easily be converted into a roped elevator without having to reduce the size of the elevator car. When a so-called rope-type hydraulic elevator has to be replaced or renewed, the invention makes it possible to use a somewhat larger elevator car, because, instead of a hydraulic cylinder placed at one side of the elevator car, only one space for the hoisting ropes is needed. The invention already allows the use of a significantly larger elevator car when the traction sheave elevator has to be renewed or replaced, because the part of the shaft width required by the counterweight and the counterweight guide rails, laterally or towards the rear wall, becomes available for accommodating the larger elevator car. Thus, for example, an elevator for 6 persons can be replaced by an elevator for 8 persons, or an elevator for 8 persons can be replaced by an elevator for 10 persons. The invention is also suitable for use in connection with larger elevators, although the most suitable application area is elevators normally used in domestic and office buildings, i.e. elevators designed for a nominal load of about 1000kg or less. The modernization or "total replacement" of an elevator according to the invention is implemented by replacing or modernizing an elevator installed in an elevator shaft or equivalent, e.g. in a space which is partly open at one side of the building but which defines the place of replacement of the elevator. Generally, modernization primarily means modernization of the hoisting function and secondarily an increase in the size of the elevator car. The updated motivation may include one or two of the above-mentioned reasons or some other reason. When an elevator has to be replaced, the elevator car and the hoisting function are generally replaced. Deep modernization of an elevator system or near complete replacement of an old elevator system is in many cases mutually exchangeable due to various economic factors.

In the elevator of the invention, normal elevator hoisting ropes, such as the commonly used steel wire ropes, are available. In elevators, it is possible to use ropes made of artificial material and ropes in which the load-bearing part is made of artificial fibre material, such as so-called "aramid" ropes ", which have been proposed in recent years for use in elevators. Available solutions also include steelReinforced flat ropes, especially because they allow a small deflection radius. Particularly suitable in the elevator of the invention are elevator hoisting ropes twisted from e.g. round and strong wires. With round wires, the rope can be twisted in many ways using wires of different or equal thickness. In the rope used in the present invention, the average wire thickness is about 0.4 mm. Suitable ropes made of strong wires are wires in which the average thickness is below 0.3mm or even below 0.2 mm. For example, thin-wire and strong 4mm ropes can be twisted from the wires in a relatively economical manner, so that the average wire thickness in the finished rope is in the range of 0.15-0.25mm, while the finest wire can have a thickness as small as only about 0.1 mm. Thin rope wires can easily be made very strong. In the present invention, a material having a thickness of greater than about 2000N/mm may be used²The strength of (3). A suitable strength range for the cord wire is 2300 plus 2700N/mm². In principle, it is possible to use a catalyst having a viscosity of up to about 3000N/mm²Or even higher strength rope wires.

The elevator of the invention, in which the elevator car is suspended by means of hoisting ropes consisting of a single rope or a number of parallel ropes, and which elevator has a traction sheave that moves the elevator car by means of the hoisting ropes, has rope portions of the hoisting ropes going upwards and downwards from the elevator car, and the rope portions going upwards from the elevator car are at a first rope tension (T)₁) The tension is then greater than a second rope tension (T) which is the rope tension of the rope portions travelling downwards from the elevator car₂). In addition, the elevator comprises a compensating system for maintaining the ratio (T) between the first rope tension and the second rope tension₁/T₂) Is substantially constant.

In the method according to the invention for manufacturing an elevator, the elevator car is connected to elevator ropes for hoisting the elevator car, which ropes consist of a single rope or a number of parallel ropes and comprise rope portions going upwards and downwards from the elevator car, and the elevator ropes are provided with a compensating systemSystem for maintaining the ratio (T) between the rope forces acting in upward and downward directions₁/T₂) Is substantially constant.

The grip between the traction sheave and the hoisting ropes can be increased by increasing the contact angle with the sheave acting together as a diverting pulley. In this way the elevator car can be made lighter and its size can be reduced, thereby increasing the space saving potential of the elevator. By using one or more diverting pulleys a contact angle between the traction sheave and the hoisting ropes of more than 180 is achieved. The requirements arising from friction need to compensate the elongation of the ropes to ensure that there is a sufficient grip between the hoisting ropes and the traction sheave for the operation and safety of the elevator. On the other hand it is of crucial importance in respect of elevator operation and safety that the rope portion below the elevator car should be kept sufficiently tight in an elevator solution without counterweight. This is not necessarily achieved using a spring or a simple lever, for example.

Drawings

The invention will be described in detail hereinafter with the aid of a few examples of its embodiments and with reference to the accompanying drawings, in which

Fig. 1 is a diagrammatic view illustrating a traction sheave elevator without counterweight according to the invention;

fig. 2 presents a diagrammatic illustration of another traction sheave elevator without counterweight according to the invention;

fig. 3 presents a diagrammatic view of a third traction sheave elevator without counterweight according to the invention;

fig. 4 presents a diagrammatic illustration of a fourth traction sheave elevator without counterweight according to the invention;

fig. 5 presents a diagrammatic view of another traction sheave elevator without counterweight according to the invention;

fig. 6 presents a diagrammatic illustration of another traction sheave elevator without counterweight according to the invention;

fig. 7 presents a diagrammatic illustration of another traction sheave elevator without counterweight according to the invention;

fig. 8 presents a diagrammatic view of another traction sheave elevator without counterweight according to the invention;

fig. 9 presents a diagrammatic view of another traction sheave elevator without counterweight according to the invention;

fig. 10 presents solutions in which the existing elevator arrangement has been replaced by a solution according to the invention.

Detailed Description

Fig. 1 presents a diagrammatic illustration of the structure of an elevator according to the invention. The elevator is preferably an elevator without machine room and has a drive machine 4 placed in the elevator shaft. The elevator presented in the figure is a traction sheave elevator without counterweight and with machine above. The passage of the elevator hoisting ropes 3 is as follows: one end of the rope is immovably fixed to a fixing point 16 fastened to a lever 15 of the elevator car 1, which fixing point is located at a distance a from a pivot 17 connecting the lever to the elevator car 1. In fig. 1 the lever 15 thus pivots on the elevator car 1 at the fixing point 17. From the fixing point 16 the hoisting ropes 3 go upwards to a diverting pulley 14 placed in the upper part of the elevator shaft above the elevator car 1, from which diverting pulley the ropes 3 go further downwards to a diverting pulley 13 on the elevator car, and from which diverting pulley 13 the ropes go again upwards to a diverting pulley 12 fitted in the upper part of the shaft above the elevator car. From diverting pulley 12 the ropes go further downwards to a diverting pulley 11 mounted on the elevator car. Having passed around this diverting pulley the ropes go again upwards to a diverting pulley 10 fitted in the upper part of the shaft and having passed around this pulley they go again downwards to a diverting pulley 9 fitted on the elevator car. Having passed around this diverting pulley 9 the hoisting ropes 3 go further upwards only in "tangential contact" with the ropes past the diverting pulley 7 and then to the traction sheave 5 of the drive machine 4 placed in the upper part of the elevator shaft. This means that the ropes 3 going from the traction sheave 5 to the elevator car 1 pass the rope grooves of diverting pulley 7, and the deflection of the ropes 3 caused by diverting pulley 7 is small, or it can be said that the ropes 3 coming from the traction sheave 5 only touch the diverting pulley 7 "tangentially". This "tangential contact" serves as a solution to damp the vibrations of the walking ropes and can also be used in other roping solutions. The ropes are passed around the traction sheave 5 of the hoisting device 4 along the rope grooves of the traction sheave 5. From the traction sheave 5 the ropes 3 go further downwards to diverting pulley 7, pass around the pulley 7 along the rope grooves of the diverting pulley 7 and return upwards to the traction sheave 5, on which traction sheave 5 the ropes 3 pass the traction sheave along the rope grooves of the traction sheave. From the traction sheave 5 the hoisting ropes 3 go further downwards in tangential contact with diverting pulley 7 past the elevator car 1 moving along the guide rails 2 to a diverting pulley 8 placed in the lower part of the elevator shaft, passing around it along the rope grooves above it. From diverting pulley 8 in the lower part of the elevator shaft the ropes go upwards to diverting pulley 18 on the elevator car, from which the ropes go further downwards to diverting pulley 19 in the lower part of the elevator shaft and further upwards to diverting pulley 20 on the elevator car, from where the ropes 3 go further downwards to diverting pulley 21 in the lower part of the elevator shaft, from where they go further to diverting pulley 22 on the elevator car, from where the ropes 3 go further to diverting pulley 23 in the lower part of the elevator shaft. From diverting pulley 23 the ropes 3 go further to a lever 15 which is pivotally fixed to the elevator car 1 at point 17, to which lever 15 one end of the ropes 3 is immovably fixed at point 24 at a distance b from the pivot 17, in which case the hoisting means and the diverting pulleys are preferably all placed on the same side of the elevator car in the situation shown in fig. 1. This solution is particularly advantageous in the case of rucksack-type elevators, in which case the above-mentioned components are arranged behind the elevator car in the space between the elevator car and the rear wall of the shaft. The hoisting machine and diverting pulleys can also be disposed in the elevator shaft in other suitable ways. The roping arrangement between the traction sheave 5 and the diverting pulley 7 is called Double wrap roping (Double wrap roping), in which the hoisting ropes are wrapped two and/or more times around the traction sheave. In this way, the contact angle may be increased by two and/or more steps. For instance in the embodiment shown in fig. 1 a contact angle of 180 +180, i.e. 360, is achieved between the traction sheave 5 and the hoisting ropes 3. The double wrap roping presented in the figure can also be arranged in another way, e.g. by placing the diverting pulley 7 on the side of the traction sheave 5, in which case a contact angle of 180 +90, i.e. 270, can be achieved as the hoisting ropes are passed twice around the traction sheave, or by placing the traction sheave in another suitable position. A preferred solution is to arrange the traction sheave 5 and the diverting pulley 7 so that the diverting pulley 7 will also function as a guide for the hoisting ropes 3 and as a damping pulley. Another good solution is to make a complete unit comprising the elevator drive machine with the traction sheave and one or more diverting pulleys with bearings at the correct working angle in relation to the traction sheave. The working angle is determined by the roping conditions used between the traction sheave and the diverting pulley/diverting pulleys, which determine the way in which the mutual position and angle between the traction sheave and the diverting pulley/diverting pulleys in relation to each other are fitted in the unit. This unit can be mounted in place as a unified unit in the same way as the drive machine. In a preferred case the drive machine 4 can e.g. be fixed to an elevator car guide rail, and the diverting pulleys 7, 10, 12, 14 in the upper part of the shaft are mounted on beams in the upper part of the shaft, which are fastened to the elevator car guide rails 2. The diverting pulleys 9, 11, 13, 18, 20, 22 on the elevator car are preferably mounted on beams placed in the upper and lower part of the elevator car, but they can also be fixed to the elevator car in other ways, e.g. by mounting all diverting pulleys on the same beam. The diverting pulleys 8, 19, 21, 23 in the lower part of the shaft are preferably mounted on the shaft floor. In fig. 1 the traction sheave engages the rope portion between diverting pulleys 8 and 9, which is a preferred solution according to the invention. In the preferred solution according to the invention the elevator car 1 is connected to the hoisting ropes 3 by means of at least one diverting pulley from which the hoisting ropes go upwards on both sides of the diverting pulley edge and at least one diverting pulley from which the hoisting ropes go downwards on both sides of the diverting pulley edge, and in which elevator the traction sheave 5 engages a part of the hoisting ropes 3 between these diverting pulleys. The roping between the traction sheave 5 and the diverting pulley 7 can also be implemented in other ways instead of double wrap roping, such as e.g. by using single wrap roping in which case diverting pulley 7 would not necessarily be needed, ESW (extended single wrap) roping, XW (X wrap) roping or some other suitable solution.

The drive machine 4 placed in the elevator shaft is preferably of flat construction, in other words the machine has a small thickness compared to its width and/or height, or at least the machine is slim enough to be accommodated between the elevator car and a wall of the elevator shaft. The machine can also be placed in different ways, e.g. by arranging the slim machine partly or completely between an imaginary extension of the elevator car and a shaft wall. In the elevator of the invention it is possible to use almost any type and design of drive machine 4 that can be fitted into the space used for it. For example, it is possible to use geared or gearless machines. The machine may have compact and/or flat dimensions. In the suspension solution according to the invention the rope speed is often higher compared to the elevator speed, so it is possible to use an uncomplicated machine as the basic machine solution. The elevator shaft is preferably provided with equipment required for the supply of power to the motor driving the traction sheave 5 and equipment required for elevator control, both of which can be placed in a common instrument panel 6 or mounted separately from each other or integrated partly or wholly with the drive machine 4. A preferred solution is a gearless machine comprising a permanent magnet motor. The drive machine may be fixed to a wall of the elevator shaft, the ceiling, a guide rail or some other structure, such as a beam or frame. Another possibility is to mount the machine on the bottom of the elevator shaft in the case of an elevator with machine below. Fig. 1 presents a preferred suspension solution, in which the suspension ratio of the diverting pulleys above the elevator car and below the elevator car is in both cases the same 7: 1. To make this ratio more visible in practice it means the ratio of the distance traveled by the hoisting rope to the distance traveled by the elevator car. The suspension arrangement of the elevator car 1 is implemented by means of diverting pulleys 14, 13, 12, 11, 10, 9, and the suspension arrangement below the elevator car 1 is implemented by means of diverting pulleys 23, 22, 21, 20, 19, 18, 8. Other suspension schemes may also be used to implement the present invention. The elevator of the invention can also be embodied in a solution comprising a machine room or the machine can be mounted movable together with the elevator. In the invention the diverting pulleys connected to the elevator car can preferably be mounted on the same beam. This beam can be fitted on top of the elevator car, on the side of the elevator car or below the elevator car, on the elevator car frame or at some other suitable place in the elevator car structure. The diverting pulleys may also be fitted separately in each case in suitable places on the elevator car and in the shaft. The diverting pulleys arranged in the shaft above the elevator car, preferably not in the upper part of the shaft, and/or the diverting pulleys arranged in the shaft below the elevator car, preferably in the lower part of the elevator shaft, may e.g. be fitted on a common anchorage, such as a beam.

The function of the lever 15 hinged on the elevator car at point 17 in fig. 1 is to eliminate rope elongations occurring in the hoisting ropes 3. On the other hand, maintaining a sufficient tension in the lower rope portion, which refers to the part of the hoisting ropes below the elevator car, is essential for the operation and safety of the elevator. By means of the lever arrangement 15 according to the invention, the tensioning of the hoisting rope and the compensation of the rope elongation can be achieved without the use of springs or weights as in the prior art. By means of the lever arrangement 15 according to the invention, it is also possible to achieve rope tensioning in such a way that rope forces T acting in different directions on the traction sheave 5₁And T₂The ratio between can be kept at a desired constant value, which can be, for example, 2, and with regard to the rope force, we can also call the rope tension. This constant ratio can be determined byVary the distances a and b because of T₁/T₂B/a, the lever 15 is hinged on the elevator car when odd suspension ratios are used in the suspension of the elevator car, and the lever 15 is hinged on the elevator shaft when even suspension ratios are used.

Fig. 2 presents a diagrammatic illustration of the structure of an elevator according to the invention. The elevator is preferably an elevator without machine room and the drive machine 204 is placed in the elevator shaft. The elevator shown in the figure is a traction sheave elevator with machine above and without counterweight, and the elevator car 201 moves along guide rails 2. The passage of the hoisting ropes 203 in fig. 2 is similar to that in fig. 1, but in fig. 2 is distinguished in that the lever 215 is immovably hinged on the wall of the elevator shaft at point 217. Since the lever 215 is hinged on the elevator shaft, preferably on the wall of the elevator shaft, not on the elevator car, which is a situation with an even suspension ratio both in the rope portion above the elevator car 1 and in the rope portion below it. The suspension above the elevator car comprises a hoisting machine 204 and diverting pulleys 209, 210, 211, 212, 213, 214. The suspension below the elevator car comprises diverting pulleys 208, 218, 219, 229, 221, 222, 223. One end of the hoisting rope is fastened to the lever 215 at a point 216, which is a distance a from the pivot 217, and the other end of the hoisting rope is fastened to the lever 215 at a point 224, which is a distance b from the pivot 217. The suspension ratio of the elevator car is 6: 1 in both the rope portion above the elevator car and the rope portion below the elevator car.

The rope length of the hoisting ropes used in elevators without counterweight is large because of the high suspension ratio. For example, in an elevator without counterweight, which is suspended with a suspension ratio of 10: 1, the same suspension ratio of 10: 1 is used both above and below the elevator car, and which elevator has a hoisting height of 25m, the rope length of the hoisting ropes is about 270 m. In this case the rope length varies up to about 50cm due to variations in rope stress and/or temperature. The need for compensating rope elongations is therefore also relatively strong. For the operation and safety of the elevator it is essential that the ropes below the elevator car are kept under a sufficient tension. This is not always possible by using a spring or a simple lever.

Fig. 3 presents a diagrammatic illustration of the structure of an elevator according to the invention. The elevator is preferably an elevator without machine room and the drive machine 304 is placed in the elevator shaft. The elevator shown in the figure is a traction sheave elevator with machine above and without counterweight, the elevator car 301 moving along guide rails 302, in fig. 3 the lever solution used in fig. 1 and 2 has been replaced by a double pulley-like member, preferably two pulleys 313 and 315, connected to each other at point 314, at which point the two tensioning pulleys are fixed to the elevator car 301. In a double pulley-like structure the pulley 315 engaging the hoisting rope portion below the elevator car has a larger diameter than the pulley 313 engaging the hoisting rope portion above the elevator car, and the diameter ratio between the diameters of the two tensioning pulleys 313 and 315 determines the magnitude of the tensioning force acting on the hoisting rope and thus the hoisting rope elongation compensating force. In this solution the use of tensioning pulleys offers the advantage that the construction can compensate even very large rope elongations. By varying the diameter of the tensioning pulleys it is possible to influence the magnitude of the rope elongation to be compensated and the rope force T acting on the traction sheave₁And T₂And this ratio can be made constant by this arrangement. The length of the ropes used in elevators is large due to the large suspension ratio or the large hoisting height. For the operation and safety of the elevator it is crucial that the hoisting rope portion below the elevator car maintains a sufficient tension and that the rope elongation to be compensated is large. This often cannot be achieved with a spring or a simple lever. In the case of odd suspension ratios both above and below the elevator car, the tension pulleys are immovably fitted in connection with the elevator car, and in the case of even suspension ratios the tension pulleys are immovably fitted in the elevator shaft or in other corresponding places not fixedly fitted to the elevator car. This solution can be implemented using the tensioning pulleys shown in figures 3 and 4, but using pulley-like membersThe number may vary, for example, it is possible to use only one pulley and to position the points where the hoisting ropes are fixed in a different diameter. It is also possible to use e.g. more than two tension pulleys so that the diameter ratio between the pulleys is changed by changing only the diameter of the tension pulleys.

In fig. 3, the hoisting ropes run as follows: the hoisting ropes are fixed at one end to a tensioning pulley 313, which is immovably attached to a pulley 315. The set of sheaves 313, 315 is mounted to the elevator car at point 314. From the pulley 313 the hoisting ropes 303 go upwards and meet a diverting pulley 312 placed above the elevator car in the elevator shaft, preferably in the upper part of the elevator shaft, passing along rope grooves provided in the diverting pulley 312. These rope grooves may or may not be coated with a friction-increasing material, such as polyurethane or some other suitable material, for example. From pulley 312 the ropes go further downwards to a diverting pulley 311 on the elevator car and, having passed around this pulley, the ropes go further upwards to a diverting pulley 310 fitted in the upper part of the shaft. Having passed around this diverting pulley 310 the ropes go downwards again to a diverting pulley 309 mounted on the elevator car, and the hoisting ropes go after passing around this pulley further upwards to a diverting pulley 307 preferably fitted near the hoisting machine 304. Between diverting pulley 307 and traction sheave 304 the figure shows an X-wrap roping in which the hoisting ropes run crosswise to the rope portion going upwards from diverting pulley 307 to traction sheave 305 and to the rope portion returning from traction sheave 305 to diverting pulley 307. The pulleys 313, 312, 311, 310, 309 together with the hoisting means form the suspension above the elevator car with the same suspension ratio as in the suspension below the elevator car, which suspension ratio is 5: 1 in fig. 3. From diverting pulley 307 the ropes go further to a diverting pulley 308 fitted in place preferably on some elevator car guide rail 302 in the lower part of the elevator shaft or on the shaft floor or in some other appropriate place, the hoisting ropes 303 go further upwards to a diverting pulley 316 fitted in place on the elevator car, after passing around diverting pulley 316 the hoisting ropes 303 go further downwards to a diverting pulley 317 fitted in place in the lower part of the elevator shaft, pass around this pulley and return to a diverting pulley 318 fitted in place on the elevator car. Having passed around diverting pulley 318 the hoisting ropes 303 go further downwards to a diverting pulley 319 fitted in place in the lower part of the elevator shaft, pass around it and then go further upwards to a tensioning pulley 315 fitted in place on the elevator car and fitted immovably to tensioning pulley 313.

Fig. 4 presents a diagrammatic illustration of the structure of an elevator according to the invention. The elevator is preferably an elevator without machine room and the drive machine 404 is placed in the elevator shaft. The elevator shown in the figure is a traction sheave elevator with machine above without counterweight, the elevator car 401 moving along guide rails 402. The passage of the hoisting ropes 403 in fig. 4 corresponds to that in fig. 3 with the difference that in fig. 4 the tensioning pulleys 413,415 are fitted in place in the elevator shaft, preferably on the bottom of the elevator shaft. Since the tensioning pulleys 413,415 are fitted in place in the elevator shaft and not connected to the elevator car, which is a case with even suspension ratios both in the rope portion above and in the rope portion below the elevator car 1. In fig. 4, the suspension ratio is 4: 1. The end of the hoisting ropes 403 below the elevator car 401 is secured to the tensioning pulley 415 having the larger diameter, and the end of the hoisting ropes above the elevator car is secured to the tensioning pulley 413 having the smaller diameter. The tension pulleys 413,415 are fitted immovably together and fixed to the elevator shaft via mounting elements 420. The suspension above the elevator car comprises hoisting means and diverting pulleys 412, 411, 410, 409, 407. The suspension above the elevator car comprises diverting pulleys 408, 416, 417, 418, 419. As shown in fig. 4, a set of tensioning pulleys (415, 413) serving as a compensating system may also advantageously be mounted in place at the bottom of the shaft, preferably a diverting pulley 419 fixed to the floor of the shaft, and in the upper part of the shaft, preferably a diverting pulley 412 fixed to the ceiling of the shaft. In which case the number of diverting pulleys required is one less in the embodiment shown in fig. 4. Thus, in this advantageous case, the installation work of the elevator is also relatively easy and relatively fast.

Fig. 5 presents a diagrammatic illustration of the structure of an elevator according to the invention. The elevator is preferably oneIn an elevator without machine room, a drive machine 504 is placed in the elevator shaft. The elevator shown in the figure is without counterweight and with a traction sheave or elevator with machine above, the elevator car 501 moving along guide rails 502. In elevators with a large hoisting height, the elongation of the hoisting rope involves a need to compensate for the rope elongation, which must be reliably achieved within certain permitted limit values. With a set of rope force compensating pulleys 524 according to the invention, as shown in fig. 5, a large displacement is obtained for compensating rope elongations, which allows to compensate larger rope elongations, which often cannot be achieved with simple lever or spring solutions. The compensating pulley according to the invention shown in fig. 5 is arranged to act on the rope force T acting on the traction sheave₁And T₂A constant ratio T is formed between₁/T₂. In the case shown in FIG. 5, the ratio T₁/T₂Equal to 2/1.

The passage of the hoisting ropes in fig. 5 is as follows. One end of the hoisting ropes 503 is fixed to a diverting pulley 525 that has been fitted to hang on the rope portion coming down from diverting pulley 514. Diverting pulleys 514 and 525 together constitute a rope force compensating system 524, which in the case of fig. 5 is a set of compensating pulleys. From diverting pulley 514 the travel of the hoisting ropes constitutes, as described in connection with the previous figures, a suspension arrangement above the elevator car between diverting pulleys 512,510, 507 fitted in place in the upper part of the elevator shaft and diverting pulleys 513,511, 509 fitted in place on the elevator car. Between the hoisting device 504 and the traction sheave 505, DW suspension is used, which is described in detail in connection with fig. 1. The roping between the diverting pulley 507 and the traction sheave can also be implemented using other suitable roping solutions, such as e.g. SW, XW or ESW suspension. From the traction sheave the hoisting ropes go further via diverting pulley 507 to a diverting pulley 508 placed in place in the lower part of the elevator shaft. Having passed around diverting pulley 508 the hoisting ropes run between diverting pulleys 518,520, 522 fitted in place in the lower part of the shaft and diverting pulleys 519,521, 523 fitted on the elevator car 501 in the manner described in connection with the preceding figures. From diverting pulley 523 the hoisting ropes 503 go further to a diverting pulley 525 comprised in the rope force compensating pulley system 514 and fastened to one end of the hoisting ropes. Having passed around diverting pulley 525 along its rope grooves, and then to an anchorage 526 at the other end of the rope in the elevator shaft or on some other appropriate place. The suspension ratio of the elevator car above and below the elevator car is 6: 1.

In the embodiment shown in fig. 5, the rope force compensating pulley system 524 compensates rope elongations by means of diverting pulley 525. This diverting pulley 525 moves over a distance I compensating the elongation of the hoisting rope 503. The compensating distance I is equal to half the rope elongation of the hoisting rope. In addition, this arrangement results in a constant tension across the traction sheave 505, the ratio T between the rope forces₁/T₂Is 2/1. The rope force compensating pulley system can also be implemented in other ways than that described in the example, for example by using more complex suspension arrangements for the rope force compensating pulleys, for example by using different suspension ratios between the diverting pulleys in the compensating pulley system.

Fig. 6 presents another embodiment using a compensating device for compensating rope elongations. In fig. 6 the passage of the ropes and the suspension ratio in the rope portions above and below the elevator car are the same as in fig. 5 described above. The hoisting ropes 603 run in the manner presented in fig. 5 between diverting pulleys 609,611, 613 mounted on the elevator car and diverting pulleys 610,612, 614 in the upper part of the elevator shaft and traction pulley 605, and the ropes go further from traction pulley 605 to the lower part of the elevator shaft to traction pulley 608 and, after passing around this pulley, run further between diverting pulleys 618,620, 622 mounted on the elevator car and 619,621, 623 mounted in the lower part of the elevator shaft, as described in connection with fig. 5. The suspension ratio of the elevator car in the rope portions above and below the elevator car is 6: 1. The elevator presented in fig. 6 differs from the situation presented in fig. 5 in the compensating device 624. Fig. 6 shows a different roping arrangement according to the invention in connection with a set of compensating sheaves 624 of the compensating device. In a set of compensating sheavesOne end 609 of the ropes 603 is immovably fitted to the elevator shaft from where the hoisting ropes go to a traction sheave 625, pass around it and go further to a diverting pulley 614, possibly fitted in place in the upper part of the elevator shaft, from where they go further to a traction sheave 605 in the manner described above. Diverting pulley 625 is fixedly fitted in conjunction with another diverting pulley 626. The two diverting pulleys 626,625 may be placed on the same shaft or they may be connected to each other by a rod or in some other suitable way. The part of the hoisting ropes 603 below the elevator car reaches, after passing around diverting pulley 623, diverting pulley 626 of the compensating device 624, which is connected to diverting pulley 625 in the manner described above. Having passed around diverting pulley 626, the hoisting ropes 603 go further to a diverting pulley 627 immovably fitted in place in the vertical and forming part of the compensating system 624. After passing around diverting pulley 627 the hoisting ropes 603 go further to an anchorage 628, to which the other ends of the hoisting ropes are immovably fixed. This anchorage 628 is on diverting pulley 625 or fixedly connected to it. With this step rope arrangement in the compensating device 624, a rope force T is obtained₁And T₂Constant ratio of T to T₁/T₂3/2. With this roping arrangement it is possible to implement SW roping on the traction sheave, in other words the diverting pulley 507 shown in fig. 5 is not completely necessary. SW can be used on the traction sheave because the illustrated roping arrangement in the compensating device 624 minimizes the required friction on the traction sheave and allows for a smaller rope force T₁And T₂. However, the diverting pulley 507 presented in fig. 5 can be used if desired, e.g. to provide tangential contact with the hoisting ropes as described in connection with the previous figures. In the compensating device 624 the roping and the number of diverting pulleys can also be varied in ways other than those described in connection with fig. 6. Via the cloth-rope suspension ratio, T, in the compensating device 624₁/T₂The ratio can be kept at a desired constant magnitude. In fig. 6, the compensation of rope elongations is implemented by means of diverting pulley 625 and diverting pulley 626 fixedly fitted to it. The shorter the rope elongation compensating distance in the compensating device, the larger the suspension ratio therein.

Figure 7 shows an embodiment of the invention in which the suspension ratio of the roping solution is 1: 1. In the elevator presented in fig. 7, the compensation of rope elongation is implemented using a lever 715, which lever 715 functions as a rope force compensating device and is immovably hinged to the elevator car 701. The rope forces are compensated to achieve the rope force T in the manner described in connection with figure 1₁And T₂Constant ratio therebetween, thus obtaining T₁/T₂Ratio of T₁/T₂B/a, regardless of the magnitude of the load. The example of embodiment of the elevator of the invention presented in fig. 7 can be implemented using e.g. the usual ropes with a diameter of 8mm in an elevator for a nominal load of 4 persons, i.e. about 700 kg. In this elevator, T₁/T₂The ratio is 1.5/1 and it uses a traction sheave with a diameter of 320mm and usually recessed rope grooves, the weight of the elevator car being 700 kg. In this case the force T lifting the elevator car upwards₁Is 1.5 times the force T acting downwards on the elevator car in order to lift the weight of the elevator car and its load₂Is the force required to lift the weight and load of the elevator car. This example is not ideal as it results in unnecessarily high rope tensions relative to the load. By increasing the suspension ratio it is possible to reduce this rope tension. The elevator of the invention can be equipped with a geared machine and can be designed e.g. according to fig. 7 with a 1: 1 roping.

Fig. 8 presents an elevator according to the invention, in which a suspension ratio of 2: 1 is used in the hoisting rope portions 803 above and below the elevator car 801 and a DW roping is used between the traction sheave 805 and the diverting pulley 807. Rope elongation compensation and rope force invariance are implemented using a rope elongation compensating device as in fig. 5, which results in a rope force ratio T₁/T₂2/1 and the compensation distance traveled by diverting pulley 825 is equal to half the magnitude of the rope elongation.

Fig. 9 presents an inventive method for compensating rope elongation and retentionOne embodiment of a constant rope force ratio. In fig. 9 the passage of the hoisting ropes is as described above in connection with fig. 6, wherein the suspension ratio of the elevator car above and below the elevator car is 6: 1. The passage of the hoisting ropes in fig. 9 differs from fig. 6 in that the ropes go downwards from diverting pulley 914 to diverting pulley 924 and in respect of the compensating system. Furthermore one end of the hoisting ropes 903 is immovably fixed to the elevator shaft at point 923, after which the ropes go to diverting pulley 922. In this figure the compensation of rope elongation is achieved by fastening diverting pulley 908 to the other end of the hoisting ropes 903 at point 926. The elongation of the hoisting ropes is compensated by allowing diverting pulley 908 to move upwards or downwards a distance equal to half the rope elongation, thereby compensating the rope elongation. In the system shown in fig. 9, compensating rope elongations and maintaining a constant rope force ratio, which is T, is implemented according to the same principle as shown in fig. 5₁/T₂And diverting pulley 908 moves a compensating distance equal to half the magnitude of the rope elongation. The compensating system presented in fig. 9 can be implemented by fastening the other end of the hoisting ropes to the diverting pulley in question by means of any diverting pulley 908,919, 921 in the lower part of the elevator shaft, as described above in connection with diverting pulley 908.

When the elevator car is suspended with a small suspension ratio, such as 1: 1, 1: 2, 1: 3 or 1: 4, diverting pulleys of larger diameter and hoisting ropes of larger thickness can be used. Smaller diverting pulleys can be used if desired below the elevator car because the tension in the hoisting ropes is lower than in the part above the elevator car, allowing smaller bending radii of the hoisting ropes to be used. In elevators with a small space below the elevator car, it is preferable to use diverting pulleys of small diameter in the rope portion below the elevator car. Since, by using the rope force compensating system of the invention, a constant tension in the hoisting rope portion below the elevator car can be achieved, according to the ratio T₁/T₂And less than the tension in the rope portion above the elevator car, which makes it possible to reduce the diverting pulleys in the rope portion below the elevator carWithout significantly affecting the service life of the hoisting ropes. For example the ratio between the diameter D of the diverting pulley and the diameter D of the rope used may be D/D < 40, and preferably this ratio may be just 25.. 30, while the ratio between the diameters of the hoisting rope portions above the elevator car and the diverting pulleys is 40. The use of diverting pulleys of smaller diameter allows the space below the elevator car to be reduced to a small size, possibly preferably only 200 mm.

A preferred embodiment of the elevator of the invention is an elevator without machine room and with machine above, in which the drive machine has a coated traction sheave, and which elevator has thin hoisting ropes of a substantially round cross-section. In which elevator the contact angle between the hoisting ropes and the traction sheave is greater than 180. The elevator comprises a unit with a mounting base on which a drive machine is fitted, as well as a traction sheave and a diverting pulley fitted at a correct angle relative to the traction sheave. The unit is fixed to the guide rails of the elevator. The elevator is made without counterweight with a suspension ratio of 9: 1 so that the roping suspension ratio above the elevator car and below the elevator car are both 9: 1 and the ropes of the elevator run in the space between one of the elevator car walls and the elevator shaft wall. The solution for compensating rope elongations of the elevator ropes comprises a set of compensating sheaves, which are set at a force T₁And T₂Form a constant ratio T₁/T₂2: 1. With the compensating sheave system used, the required compensating distance is equal to half the magnitude of the rope elongation.

Another preferred embodiment of the elevator of the invention is an elevator without counterweight, in which the suspension ratio above the elevator car is 10: 1 below. In this embodiment, the usual elevator hoisting ropes, preferably ropes of 8mm diameter, are used, and the traction sheave is made of cast iron at least in the area of the rope grooves. The traction sheave has concave rope grooves and a diverting pulley is used to adjust the contact angle of the rope on the traction sheave to 180 or more. When using normal 8-mm ropes, the traction sheave diameter is preferably 340 mm. Each one ofThe diverting pulleys are larger pulleys having a diameter of 320, 330, 340mm or even larger when using normal 8-mm hoisting ropes. The rope forces remain unchanged so that the ratio T between them₁/T₂Is 3/2.

Fig. 10a and 10b show another example situation in which a roped elevator with counterweight shown in fig. 10a has been replaced or modernized into a roped elevator without counterweight according to the invention shown in fig. 10 b. The elevator presented in fig. 10a is a roped elevator with counterweight 1003, in which elevator the counterweight and counterweight guide rails, as can be seen from the door opening 1006, are placed behind the elevator car 1001 moving along the guide rails 1002 in the space between the elevator car 1001 and the shaft wall 1005 in the elevator shaft 1007. Fig. 10b shows how the space required for the counterweight 1003 and its guide rails 1004 is eliminated in the elevator shaft and, when necessary, the space thus freed up can be used for the elevator car 1001. This provides a possibility to install a larger elevator car in the same shaft. In the case of a conventional passenger elevator as shown in fig. 10b, it is possible to obtain an additional elevator car depth of e.g. about 20-25cm or even more when the elevator shown in fig. 10a is replaced or modernized into an elevator without counterweight as shown in fig. 10 b.

Fig. 10c and 10d show another example situation in which a roped elevator with counterweight shown in fig. 10c has been replaced or modernized into a roped elevator without counterweight according to the invention shown in fig. 10 d. In the roped elevator with counterweight presented in fig. 10c, the counterweight 1003 and its guide rails 1004, as seen from the door opening 1006, are placed on one side of the elevator car 1001. Fig. 10d presents how, according to the invention, the elevator in fig. 10c is replaced by or modernized into a roped elevator without counterweight according to the invention. The space vacated in the elevator shaft 1007 by removing the counterweight 1003 and its guide rails 1004 can be used for the elevator car 1001 so that the width of the elevator car 1001 is increased. In the case of a conventional passenger elevator as shown in fig. 10d, it is possible to obtain an additional elevator car width of e.g. about 10-20cm or even more when the elevator shown in fig. 10c is replaced or modernized into an elevator as shown in fig. 10 d.

Fig. 10e and 10f show a third example situation in which a side-lift hydraulic elevator as shown in fig. 10e has been replaced or modernized into an elevator without counterweight according to the invention as shown in fig. 10 f. The hydraulic elevator in fig. 10e comprises a hydraulic cylinder 1009 belonging to the hydraulic lifting device, a diverting pulley 1008 comprised in the hoisting rope system and its possible guide rails, as seen from the door opening 1006, all placed on one side on the elevator car 1001. In the situation shown in fig. 10e the elevator car 1001 is lifted from one side on the elevator car along the guide rails 1002, but the hoisting function can also be implemented in some other way. The hydraulic lifting function to be replaced or renewed can also consist of a system which exerts a lifting force from below the elevator car. Fig. 10f presents schematically how, according to the invention, the elevator in fig. 10e is replaced by or modernized into a roped elevator without counterweight according to the invention. The space vacated in the elevator shaft 1007 by removing the hydraulic lifting appliance and possibly the counterweight can be used for the elevator car 1001 so that the width of the elevator car 1001 is increased. In the case of a conventional passenger elevator as shown in fig. 10f, it is possible to obtain an additional elevator car width of e.g. about 5-15cm or even more when the elevator shown in fig. 10e is replaced or modernized into an elevator without counterweight as shown in fig. 10 f.

It is obvious to the person skilled in the art that different embodiments of the invention are not limited to the examples described above, but that they may be varied within the scope of the invention. For example, although some additional advantages may be achieved by using a number of rope passages, the number of times the hoisting ropes are passed between the upper part of the elevator shaft and the elevator car and between the elevator car and the diverting pulleys below it is not a decisive question as regards the basic advantages of the invention. Normally it is implemented so that the ropes go to the elevator car as many times from above as from below, so that the suspension ratios of the diverting pulleys going upwards and the diverting pulleys going downwards are the same. It is also obvious that the hoisting ropes do not necessarily need to pass under the elevator car. In accordance with the examples described above, the skilled person can vary the embodiment of the invention and the traction sheave and rope sheave, instead of being coated metal sheaves, may also be uncoated metal sheaves or uncoated sheaves made of some other material suited to the purpose.

It is further obvious to the person skilled in the art that the traction sheave and rope pulleys of metal or some other suitable material used in the invention, which function as diverting pulleys and are coated with a non-metallic material at least in the area of their rope grooves, may have a coating made of e.g. rubber, polyurethane or some other material suited to the purpose.

It is also obvious to the person skilled in the art that the elevator car and the machine unit can be arranged in the cross-section of the elevator shaft in a manner differing from the lay-out described in the examples. Such a different lay-out is e.g. a lay-out in which the machine is located behind the elevator car as seen from the shaft door and the ropes are passed under the elevator car in a diagonal direction with respect to the bottom of the elevator car. When the suspension of the elevator car on the ropes is constituted by other types of suspension lay-ups in a symmetrical relationship with respect to the centre of mass of the elevator, it can be advantageous to let the ropes pass under the elevator car in a diagonal or otherwise oblique direction with respect to the shape of the bottom.

It is further obvious to the person skilled in the art that the equipment needed for the supply of power to the motor and the equipment needed for elevator control can be placed elsewhere than in connection with the machine unit, e.g. in a separate instrument panel, or the equipment needed for control can be implemented as a separate unit, which can be placed in a different place in the elevator shaft and/or in other parts of the building. It is also obvious to the skilled person that an elevator using the invention can be equipped in a different way than in the examples described above. It is further obvious to the skilled person that the elevator of the invention can be implemented using almost any type of flexible hoisting means as hoisting ropes, e.g. flexible rope of one or more strands, flat belt, cogged belt or some other type of belt suited to the purpose. It is also obvious to the skilled person that the replacement or modernization of a drum elevator, a spiral-driven elevator or an elevator with a hoisting function based on almost any other technology can also be accomplished according to the invention with a traction sheave elevator without counterweight according to the invention.

It is also obvious to the skilled person that instead of using ropes with filler, the invention can be implemented using ropes without filler, which are either lubricated or unlubricated. Furthermore, it is also obvious to the person skilled in the art that the rope can be twisted in many different ways.

It is also obvious to the person skilled in the art that the elevator of the invention can be implemented using different roping arrangements between the traction sheave and the diverting pulley/diverting pulleys to increase the contact angle a to be larger than those described as examples. It is for instance possible to arrange the diverting pulley/diverting pulleys, the traction sheave and the hoisting ropes in some other way than in the roping arrangements described in the examples. It is also obvious to the skilled person that in the elevator of the invention the elevator can also be provided with a counterweight, in which case the counterweight has e.g. a weight below the weight of the elevator car and is suspended by a separate roping arrangement.

Due to the resistance of the rope pulleys used as diverting pulleys and due to the friction between the ropes and the pulleys and possible losses occurring in the compensating system, the ratio between the rope tensions may deviate somewhat from the nominal ratio of the compensating system. Even a deviation of 5% will not cause any significant disadvantages, since the elevator must in any case have some inherent robustness.

Claims (23)

1. Elevator without counterweight, in which the elevator car is suspended by means of hoisting ropes consisting of a single rope or several parallel ropes, said elevator having a traction sheave which moves the elevator car by means of the hoisting ropes, characterized in that: the elevator has rope portions of the hoisting ropes going upwards and downwards from the elevator car, and the rope portions going upwards from the elevator car are at a first rope tension (T)₁) The first rope tension is lower than the second rope tension (T)₂) The second rope tension (T)₂) Of rope portions descending from the elevator carRope tension, wherein the ratio of the rope tension across the traction sheave is constant, and which elevator is built to replace or be built by making various modifications in an existing elevator installed in an elevator shaft.

2. An elevator according to claim 1, characterized in that: the existing elevator is a hydraulic lift elevator.

3. An elevator according to claim 1, characterized in that: the existing elevator is a traction sheave elevator.

4. Elevator as defined in any one of the preceding claims, characterized in that: the elevator car of the elevator has a floor area that is larger than that of existing elevators.

5. An elevator according to any one of claims 1-3, characterized in that: the elevator has a compensating device.

6. An elevator according to claim 5, characterized in that: the compensating device is a lever, a set of tension pulleys or a compensating pulley.

7. An elevator according to any one of claims 1-3, characterized in that: the elevator has a compensating device and the compensating device comprises one or more diverting pulleys.

8. An elevator according to any one of claims 1-3, characterized in that: the continuous contact angle between the traction sheave and the hoisting ropes is at least 180.

9. Elevator according to any one of claims 1-3, which comprisesIs characterized in that: the hoisting ropes used are those having a mass of more than 2000N/mm²The strength of (2) is high.

10. An elevator according to any one of claims 1-3, characterized in that: the hoisting ropes have a diameter of less than 8 mm.

11. An elevator according to claim 10, characterized in that: the diameter of the hoisting ropes is between 3-5 mm.

12. An elevator according to any one of claims 1-3, characterized in that: the weight of the lifting device is much less than the load.

13. An elevator according to any one of claims 1-3, characterized in that: the traction sheave is weighted with polyurethane or rubber.

14. An elevator according to any one of claims 1-3, characterized in that: the traction sheave, at least in the area of the rope grooves, is made of metal.

15. An elevator according to claim 14, characterized in that: the metal is cast iron.

16. An elevator according to claim 14, characterized in that: the traction sheave has a concave rope groove.

An elevator according to any one of claims 1-3, characterized in that: the D/D ratio of the diverting pulleys below the elevator car is below 40.

18. Method for replacement installation in an elevator shaftTo form an elevator without counterweight or by making various modifications in the existing elevator, characterized in that: a hoisting function arrangement to replace the hoisting function of an existing elevator is installed, comprising a set of hoisting ropes, which set of hoisting ropes comprises one rope or a plurality of parallel ropes; and equipment for the elevator driving the hoisting ropes, and the elevator car of the elevator to be formed is connected to the hoisting ropes in such a way that the elevator has rope portions going upwards and downwards from the elevator car, and the elevator roping arrangement is provided with a compensating system for maintaining a substantially constant ratio (T) between the rope forces acting in the upwards and downwards direction₁/T₂)。

19. The method of claim 18, wherein: the alternative lift function is installed at the site of a hydraulic lift function.

20. The method of claim 18, wherein: the alternative hoisting function is installed in a place of a traction sheave operated hoisting function comprising a counterweight.

21. The method of claim 18, wherein: the alternative lift function device is installed to replace a lift function device implemented using a drum or a screw.

22. The method of claim 18, wherein: the equipment comprised in the hoisting function of the existing elevator is removed from the elevator shaft.

23. The method of claim 18, wherein: a replacement elevator car having a size larger than the existing elevator car is formed in the elevator shaft.