The present invention relates to an elevator as defined in the preamble of claim 1 and to an elevator hoisting machine as defined in the preamble of claim 11.

The present invention concerns in the first place an elevator without machine room provided with a discoid substantially flat hoisting machine mounted substantially on one or more guide rails in an elevator shaft. As seen from above, the hoisting machine is thus placed e.g. in the space between the elevator car and a wall of the shaft.

In prior art, arrangements for mounting an elevator hoisting machine are known wherein the hoisting machine is fixed to the guide rails in the elevator shaft. One prior-art solution is disclosed in specification EP 0688735. This solution describes a flat machine structure for use in elevators which is place in the elevator shaft so that no separate machine room is needed. The machine is fixed to a guide rail in the elevator shaft either directly or by means of a suitable auxiliary frame. Typically, the hoisting machine is so mounted on the guide rail by means of the auxiliary frame that the hoisting machine lies completely on one side of the elevator guide rail. This solution works well at low speeds, but at higher speeds the machine undergoes vibrations, which have to be eliminated by using an unsymmetrical mass body attached e.g. to the auxiliary frame or equivalent. The problem is that such a mass body increases the thickness of the mounting structure in the depthwise direction, which is why this type of struc¬ ture is not suited for use in narrow shafts.

A drawback in all prior-art solutions is the space required in the elevator shaft due to the placement of the machine. The size of the machine itself and the size of the mounting base of the machine take up space in the cross-sectional area of the elevator, thus reducing e.g. the cross-sectional area of the elevator car that can be accommodated in the shaft. The object of the present invention is to overcome the above- mentioned drawbacks and create a space-saving elevator mount¬ ing arrangement of economical cost that allows the use of a larger elevator in the same elevator shaft and enables a lower bending moment applied to the structure.

The elevator of the invention is characterized by what is dis¬ closed in the characterization part of claim 1 and the eleva¬ tor hoisting machine of the invention is characterized by what is disclosed in the characterization part of claim 11. Other embodiments of the invention are characterized by what is dis¬ closed in the other claims. Inventive embodiments are also presented in the description part and drawings of the present application. The inventive content disclosed in the applica- tion can also be defined in other ways than is done in the claims below. The inventive content may also consist of sev¬ eral separate inventions, especially if the invention is con¬ sidered in the light of explicit or implicit sub-tasks or in respect of advantages or sets 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.

The advantages of the elevator and elevator hoisting machine of the invention include a saving on transverse space in the elevator shaft, so that the same space can accommodate e.g. an elevator car of a larger cross-section. The mounting arrange¬ ment utilizes the free space available in the machine, which space preferably remains above the traction sheave. When the machine is suspended according" to the invention on an overhead beam system fixed to the guide rails, a space corresponding to the thickness of the mounting- beam is saved on the sides of the machine, this space saving- being even as much as about 10 cm in a preferred case. This is a significant addition to the size of the elevator car. Further advantages are firmness of the mounting solution and th.e fact that the bending moment applied to the structure from the machine is reduced because the machine is suspended in a centric manner in relation to the hoisting ropes.

In the following, the invention will be described in detail with reference to an embodiment example and the attached draw¬ ings, wherein

Fig. 1 presents a diagrammatic top view of an elevator structure in which the mounting arrangement of the invention is applicable Fig. 2 presents the mounting arrangement of the invention at the upper end of an elevator shaft in a front view seen obliquely from above, and Fig. 3 presents a top view of the mounting arrangement of Fig. 2 at the upper end of the elevator shaft.

Fig. 1 presents a diagrammatic representation of an elevator structure in which the mounting arrangement of the invention can well be used. The elevator is preferably an elevator with- out machine room with the hoisting machine 6 placed in the elevator shaft. The elevator presented in the figure is a traction sheave elevator with machine above. The hoisting ropes 3 of the elevator are disposed e.g. in such manner that one end of the hoisting ropes 3 is immovably secured to a fix- ing point 12 in the upper part of the of the shaft above the path of a counterweight 2 moving along counterweight guide rails 11, from where the ropes go downwards and meet diverting pulleys 9 suspending the counterweight and rotatably mounted on the counterweight 2. From diverting pulleys 9, the ropes 3 go further upwards via the rope grooves of a diverting pulley 5 to the traction sheave 7 of the hoisting machine 6, passing around it along the rope grooves of the traction sheave 7. From the traction sheave 7, the ropes go further downwards back to diverting pulley 5, passing around it along the rope grooves of the diverting pulley and returning back up to the traction sheave 7, around which the ropes pass a second time along the rope grooves of the traction sheave. From the trac- tion sheave 7, the ropes 3 go further downwards via the rope grooves of diverting pulley 5 to the elevator car 1 moving along the car guide rails 10 of tlαe elevator, the ropes being passed under the elevator car and around diverting pulleys 4, by means of which the elevator car is suspended on the ropes. The ropes 3 go further upwards from the elevator car to a fix¬ ing point 13 in the upper part of the of the shaft, where the second end of the ropes 3 is immovably secured.

In a preferred case, the fixing point 12 in the upper part of the of the shaft, the traction sheave 7, diverting pulley 5 and the diverting pulley 9 suspending the counterweight on the ropes are so disposed with respect to each other that both the rope portion from the fixing point 12 to the counterweight and the rope portion from the counterweight 2 over diverting pul¬ ley 5 to the traction sheave 7 axe substantially parallel to the path of motion of the counterweight 2. In another prefer¬ able solution the fixing point 13 in the upper part of the of the shaft, the traction sheave 7, diverting pulley 5 and the diverting pulleys 4 suspending the elevator car on the ropes are so disposed with respect to each other that both the rope portion from the fixing point 13 to the elevator car 1 and the rope portion from the elevator car 1 over diverting pulley 5 to the traction sheave 7 are substantially parallel to the path of motion of the elevator car 1. With this arrangement, no additional diverting pulleys are needed to dispose the pas¬ sage of the ropes in the shaft.

The roping between the traction slαeave 7 and diverting pulley 5 is referred to as Double Wrap roping, wherein the hoisting ropes are passed around the traction sheave twice and/or more than twice. In this way the contact angle can be increased in two and/or more stages. For example, the contact angle be¬ tween the traction sheave 7 and tlie hoisting ropes 3 achieved in the embodiment presented in Fig. 1 is 180° + 180°, i.e. 360°. The Double Wrap roping presented the figure can also be arranged in another way, such as e.g. by placing the divert¬ ing pulley on the side of the traction sheave, so that as the hoisting ropes run twice around the traction sheave, the con¬ tact angle will be 180° + 90°, i.e. 270°, or by placing the diverting pulley at some other suitable point. The effect of the rope suspension on the elevator car 1 is substantially centric if the rope pulleys 4 suspending the elevator car are disposed substantially symmetrically with respect to the ver¬ tical center line passing via the mass center of the elevator car 1. An advantageous solution is to place the traction sheave 7 and diverting pulley 5 so that the diverting pulley 5 simultaneously functions as a guide of the hoisting ropes 3 and as a damping pulley.

The drive machine 6 placed in the elevator shaft is prefera¬ bly of a flat construction, in other words, the machine has a small thickness dimension as compared to its width and/or height, or at least the machine is slim enough to be accommo¬ dated between the elevator car and a wall of the elevator shaft. The machine may also be placed differently, e.g. by disposing the slim machine partly or completely between an imaginary extension of the elevator car and a shaft wall.

The elevator shaft is advantageously provided with equipment required for the supply of power to the motor driving the traction sheave 7 as well as equipment needed for elevator control, both of which can be placed in a common instrument panel 8 or mounted separately from each other or integrated partly or wholly with the drive machine 6. The drive machine 6 may be a geared or a gearless machine. A preferable solu¬ tion is a gearless machine comprising a permanent magnet mo¬ tor.

An advantageous solution is to build a complete unit in are pre-fitted both the elevator drive machine with the traction sheave and the diverting pulley/diverting pulleys used to in- crease the contact angle along with their bearings, mounted in the correct operating angle relative to the traction sheave. The operating angle is determined by the roping used between the traction sheave and the diverting pulley/diverting pul- leys, which defines how the relative positions of the traction sheave and the diverting pulley/diverting pulleys are pre- fitted with respect to each other. This unit can be secured in place as a complete assembly like a drive machine. The drive machine can be secured in place to the wall or ceiling of the elevator shaft, to a guide rail or guide rails or to some other structure, such as a beam or frame.

Fig. 1 illustrates the advantageous 2:1 suspension, but the invention can also be implemented in an elevator having a sus- pension ratio of 1:1, in other words, in an elevator in which the hoisting ropes are connected directly without a diverting pulley to the counterweight and the elevator car. The inven¬ tion can also be implemented using other suspension solutions. For example, the elevator of the invention may be implemented using a suspension ratio of 3:1 or 4:1 or even higher suspen¬ sion ratios. The suspension of the counterweight and the ele¬ vator car may also be such that the counterweight is suspended with a suspension ratio of n:l while the car is suspended with a suspension ratio of m:l, where m is an integer and at least 1 and n is an integer and higher than m.

The arrangement for mounting a hoisting machine as presented in the example of an embodiment according to the invention comprises a stiffener 23 secured to the frame 19 of the hoist- ing machine, which frame 19 carries a stator and is hereinaf¬ ter called the stator frame, which stiffener reinforces the stator frame and is in a substantially vertical position when installed in the elevator shaft, extending along the center line of the stator frame substantially over the entire stator frame. The stiffener 23 may be a fixed part of the stator frame 19, i.e. made of the same casting, or the stiffener may be a separate body fastened to the stator frame. In addition, it is possible to fit to the stator frame 19 at least one mass body 22 as a fixed part, which is arranged to render the mass distribution or bending stiffness of the stator frame substan¬ tially unsymmetrical.

Fig. 2 illustrates an arrangement regarding the upper ends of the guide rails 10 of the elevator car in the elevator shaft. This example concerns an elevator structure different from the elevator structure presented in Fig. 1. At the upper end 10 of the guide rails 10 is a substantially horizontal frame-like steel structure 20 connecting the upper ends of the guide rails 10 to each other. The frame-like structure 20 comprises at least a substantially horizontal supporting beam 15 with two diverting pulleys 16 rotatably mounted on it, the elevator hoisting machine being- suspended at the middle of it by means of a vertical fixing element 18. The frame-like structure com¬ prises additionally a diverting pulley 14 and mounting holes to allow the guide rail structure to be secured to the shaft. The fastening to the shaft wall or equivalent is implemented using e.g. fastening bolts 21.

In the lower part of the stiffener 23 stiffening and support¬ ing the hoisting machine is a cylindrical projection 24 dis¬ posed near the traction sheave at a suitable distance below the traction sheave and directed from the stiffener 23 towards the hoisting machine, i.e. away from the elevator car 1. The projection 24 forms an axle for diverting pulley 5, which is mounted with bearings on the projection 24 so as to be freely rotatable below the traction sheave 7. The diverting pulley 5 enables double-wrap roping as described above, which can be used to increase the contact angle on the traction sheave 7 and thus the gripping force produced by friction. The divert¬ ing pulley 5 is of substantially equal size with the traction sheave 7 in diameter, and therefore the diverting pulley 5 can also serve as a damping pulley, in which case the ropes 3 go¬ ing from the traction sheave 7 to the counterweight 2 and to the elevator car 1 run via the rope grooves of the diverting pulley 5 and the deflection of the ropes caused by the divert¬ ing pulley 5 is very small. The ropes going from the traction sheave thus only run in tangential contact with the diverting pulley 5. Such tangential contact functions as a solution for damping rope vibrations and it can also be applied in other roping solutions, such as e.g. the so-called single-wrap sus¬ pension. The diverting pulley 5 may also be of a different size in diameter as compared to the diameter of the traction sheave. By means of this diverting pulley 5, it is also pos- sible to implement so-called X-wrap suspension, wherein the hoisting ropes are so arranged that they run crosswise rela¬ tive to each other so that the hoisting ropes going to the traction sheave and the hoisting ropes returning from the traction sheave cross over each other. In this case the di- verting pulley 5 is pre-fitted to- the mounting comprised in the stiffener 23, by means of which stiffener the diverting pulley can be quickly and easily fitted directly in place at the correct angle with respect to the traction sheave.

Fig. 2 shows clearly the recessed structure of the upper part of the stiffener 23. This structure is characteristic of the idea of the invention and it forms a recess 17 immediately above the traction sheave. The traction sheave is not shown in Fig. 2. Trie recess 17 extends from the stiffener 23 towards the hoisting machine, i.e. away from the elevator car 1 in the embodiment example according to the invention. The figure does not show the mounting holes in the back wall of the recess 17 through which the stiffener 23, which is fastened to the hoisting machine, is secured to the fixing element 18, which is a beam having the shape of e.g. a rectangular tube in cross-section. When mounted, the lower end of the fixing ele¬ ment 18 remains inside the recess 17. The fixing element 18 is thus substantially above the traction sheave 7 and substan¬ tially inside the vertical volume formed by the cross-section of the traction sheave 7. The upper end of the fixing element 18 is secured e.g. with fastening bolts to the supporting beam 15 as mentioned above. Fig. 3 presents the solution of the invention in top view. Fig. 3 shows that the elevator according to the embodiment example is a so—called rucksack-type elevator with an elevator car 1 moving on one side of the guide rail line formed by the guide rails 10, being guided by guide rollers 25. The cross- section of the xectangular frame-like steel structure 20 en¬ closes the counterweight 2 and its guide rails 11 and most of the hoisting machine of the elevator. From Fig. 3 we can eas- ily see how this arrangement has made it possible to move the hoisting machine away from the elevator car by placing the fixing element 18 of the hoisting machine in the recess 17 provided in the upper part of the stiffener 23 and having the cross-sectional shape of a U-beam opening towards the elevator car 1, as close to the surface of the stator frame 19 facing towards the elevator car 1 as possible. In this direction the elevator car 1 can have a width larger by a corresponding dis¬ tance.

It is obvious to the person skilled in the art that the inven¬ tion is not limited to the embodiments described above, but that it may be varied within the scope of the inventive con¬ cept defined in the claims presented below. Thus, the inven¬ tion is not necessarily limited e.g. to double-wrap-type ele- vators, but the hoisting machine can be mounted in the same way in single-wrap-type elevators in which diverting pulley 5 is placed as described above but the hoisting ropes are passed only once around the traction sheave. In this case the hoist¬ ing ropes can also be caused to run crosswise over each other by means of the diverting pulley 5, allowing the contact angle on the traction sheave to be increased beyond 180 degrees. In addition it is obvious to the person skilled in the art that diverting pulley 5 can also be left out altogether, depending on the suspension solution.

It is likewise obvious to the skilled person that the place and manner of suspension may differ from the above descrip- tion. Similarly, the structure of the stiffener and its and integration with the frame comprising the stator may differ from the above description.

It is also obvious to the person skilled in the art that the mutual structure and fit of the recess 17 and the fixing ele¬ ment 18 can be implemented in different ways. The recess 17 may be replaced with e.g. a rectangular pin-like structure or equivalent with a hollow fixing element fastened onto it and having an interior space of a cross-sectional shape corre¬ sponding to the pin-like structure but being larger enough to allow the fixing element to be fitted onto the pin-like struc¬ ture ovex a sufficiently long distance. Likewise, the mounting may be implemented using pairs of fastening brackets or equivalent. Anyway, a feature common to all fixing solutions is that the fixing is implemented in the free space remaining above the cross-section of the traction sheave.

It is further obvious that the solution of the invention can as well be applied in elevator solutions without counter¬ weight, too.