WO2013068648A1

WO2013068648A1 - Method and arrangement for measuring the balance of an elevator and method for balancing the elevator

Info

Publication number: WO2013068648A1
Application number: PCT/FI2012/051091
Authority: WO
Inventors: Jari ÖSTERMAN; Juha Taavela
Original assignee: Kone Corporation
Priority date: 2011-11-07
Filing date: 2012-11-07
Publication date: 2013-05-16
Also published as: WO2013068648A9

Abstract

The object of the invention is a method and an arrangement for measuring the balance of an elevator in an elevator, in which method an elevator car (1) provided with one or more counterweights (3) is stopped at a desired point in the elevator hoistway (2) and at least one brake of the elevator is opened. For measuring the balance of the elevator a force directed downwards is exerted on the elevator car (1) with a separate balancing device (6), the magnitude of which force is measured with a force measuring means (12) and the measured force is converted into a simulated load of the elevator car (1) in the units of weight desired.

Description

METHOD AND ARRANGEMENT FOR MEASURING THE BALANCE OF AN ELEVATOR AND METHOD FOR BALANCING THE ELEVATOR The present invention relates to a measuring method as presented in the preamble of claim 1 and an arrangement as presented in the preamble of claim 9 for measuring the balance of an elevator, and a balancing method as presented in the preamble of claim 18.

From the viewpoint of the operation of an elevator, the measuring of the balance of an elevator before handing the elevator over for general use is an extremely important procedure. Precise measurements of the balance of the elevator are needed, inter alia, after the manufacture of a new elevator and, in elevators being modernized, before the commencement of modernization and also after modernization before handing the elevator over for use. The aim of the measuring of the balance is to ascertain how much weight must be added, or deducted, to the counterweight or compensating weights e.g. after some modification made to the elevator structure, such as after automatic doors are added to the elevator car. In solutions according to prior art, the measuring of the balance of elevators is generally performed using test weights of known masses. By the aid of test weights of known masses, the measuring of the balance of an elevator can be performed accurately, but a drawback is the large amount of work and the awkward transport arrangements for heavy test weights. For example, a means of transport that is sufficiently large is needed for transporting test weights weighing several hundred kilos. Just the transportation and transfer of the test weights in this case easily doubles the amount of work time needed for the measuring of the balance, in which case the balancing work also increases. The aim of the present invention is to eliminate the aforementioned drawbacks and to achieve an inexpensive, reliable and easily realizable method and arrangement for measuring the balance of an elevator. In addition, one aim is to achieve a method and an arrangement for measuring the balance of an elevator, in which carryings and transfers of test weights are not needed and in which the measuring of the balance of the elevator is faster to perform than prior-art solutions implemented with test weights. The measuring method according to the invention is characterized by what is disclosed in the characterization part of claim 1. Correspondingly, the arrangement of the invention is characterized by what is disclosed in the characterization part of claim 9. The balancing method according to the invention is characterized by what is disclosed in the characterization part of claim 18. The characteristic features of other embodiments of the invention are presented in the other claims. The invention can be implemented e.g. such that a force effect simulating a load, in practice in practice a support force resisting upward movement of the elevator car, is exerted on the elevator car with a separate auxiliary device, which force effect is measured. When balancing an elevator, preferably weight is added or removed from the counterweight until the force effect simulating a load corresponds in its magnitude to the desired balanced load, e.g. one-half of the nominal load of the elevator. In addition, or in some cases instead of, the weight of the counterweight being changed, the weight of the elevator car can be changed by removing or adding weight belonging to the own mass of the elevator car, e.g. separate ballast weights. The magnitude of the force effect is preferably measured with a force sensor belonging to the auxiliary device, or brought into connection with the auxiliary device, or with the load-weighing device of the elevator. A lever arrangement is preferred as an auxiliary device for use in implementing the invention, with which lever arrangement the elevator car or the floor of the elevator car is pressed downwards. Preferably the lever arrangement comprises a rigid beam, which is supported at one of its ends on the elevator car, at its opposite end on the floor of the floor level of the elevator and between the ends, preferably in the area of the door opening between the elevator hoistway and the floor level, or in the proximity of said area, on the wall of the elevator hoistway or on another rigid structure of the building.

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

One advantage, among others, of the solution according to the invention is that in the solution according to the invention transportation and transfer of test weights are avoided, in which case a solution for measuring the balance of an elevator is achieved that is faster and more advantageous in terms of its costs than currently. In addition, the solution according to the invention is simple and operationally reliable and also as the device solution is so light that it can be carried and handled by one person. Another advantage is also that a force corresponding to test weights can be easily transferred to the elevator car or to another suitable location, and sufficient accuracy for measuring of the balance is easily obtained with the calibrating force sensors used in the solution. One advantage is also that the solution according to the invention can be used in different elevator hoistways without fixed installations. Thus the solution according to the invention can be applied in different elevators for measuring the balance of all the elevators regardless of the different structures of the hoistway systems and load- weighing systems.

In the following the invention will be described in more detail by the aid of some examples of its embodiment with reference to the attached simplified drawings, wherein presents a simplified and diagrammatic view of one preferred solution according to the invention as viewed from the side of the elevator car,

presents a magnified view of a fixing point in the wall of the elevator hoistway of the bottom end of a fixing means of the solution according to Fig. 1, as viewed from the side of the elevator car,

presents a magnified view of the bottom end of a fixing means of the solution according to Fig. 1, as viewed from the rear of the elevator car,

presents a magnified detail of one second preferred embodiment of a balancing device to be used , in the solution according to the invention, as viewed from the side of the elevator car,

presents a simplified and diagrammatic view of one second preferred solution according to the invention for balancing an elevator, as viewed from the side of the elevator car, presents a simplified and diagrammatic view of a part of a balancing solution for an elevator according to Fig. 5, as viewed from the front of the elevator car,

presents a side view of a balancing device, to be used in a solution according to the invention, for achieving the force to be used in the balancing, in its initial position, presents a side view of a balancing device, to be used in a solution according to the invention, for achieving the force to be used in the balancing, when performing the balancing and

presents a simplified and diagrammatic view of one third preferred solution according to the invention for balancing an elevator, as viewed from the side of the elevator car.

The underlying idea for implementing the invention is to use a balancing device 6 comprising a lever arrangement to push the elevator car 1 or the floor le of the elevator car or some other suitable point, such as the floor of the floor level 2a, and thereby to simulate a load in the elevator car 1. The force simulating a load caused by pushing with the lever arrangement on the elevator car 1 or on the floor of the floor level 2a is measured with a sensor functioning as a force measuring means 12, or with a measuring means, either disposed in the lever mechanism or separate, e.g. between the lever arrangement and the floor of the elevator car 1 or of the floor level 2a. Preferably the lever arrangement to be used for measuring the balance of an elevator comprises a rigid beam functioning as a transmission means 10, which is supported at one of its ends on the elevator car 1, at its opposite end on the floor of the floor level 2a and between the ends, preferably in the area of the door opening 5 between the elevator hoistway 2 and the floor level 2a, or in the proximity of said area, on the wall of the elevator hoistway 2 or on another rigid structure of the building. A power means functioning as a moving means 8 is configured to act on the rigid beam, said moving means being e.g. a trapezoidal screw, a hydraulic jack or other jack, or a movement nut, in the support between either the floor of the floor level 2a and the end of the beam, or in the support of a support point/hinge point between the ends of the beam, on a fixed structure of the building or on the structures of the elevator car 1. Practical implementations can vary the idea, particularly with respect to the structural solutions to be used.

Fig. 1 presents a simplified and diagrammatic view of one preferred arrangement according to the invention for measuring the balance of an elevator. The solution in Fig. 1 is presented as viewed from the side of the elevator car 1, simplified and sectioned, such that at least the inside part of the elevator car 1, the elevator hoistway 2, the counterweight 3, some of the hoisting ropes 4 and one floor level 2a can be seen. The elevator car 1 is in this case at such a floor level 2a that the counterweight 3 is at essentially the same height as the elevator car 1, in which case the weight difference of the hoisting ropes 4 on the elevator car 1 side and on the counterweight 3 side does not distort the measuring result. In practice a small height difference between the elevator car 2 and the counterweight 3 does not produce a large error because of the weight difference of the hoisting ropes 4 and, in addition, the aforementioned error can be calculated separately and taken into account in the final results. During the measuring of the balance of an elevator, in all embodiments of the invention the elevator is de-energized of voltage and the brake of the elevator is opened. When the balance of an elevator is being inspected, the open door 5 of the elevator car 1 is presented with a dashed line.

The elevator car 1 is suspended in the elevator hoistway 2 supported by the hoisting ropes 4, which hoisting ropes 4 are fixed to a car sling la fixed around the elevator car 1, which comprises at least e.g. a bottom beam lb, side beams lc, of which only the side beam remaining behind the elevator car is presented with a dashed line, and a top beam Id. The fixing of the hoisting ropes 4 to the elevator car 1 can also be different. For example, in some solutions a car sling la is not required at all.

The balancing device 6 of an elevator to be used in the arrangement according to the invention is disposed to rest on a suitable floor level 2a, e.g. at such a floor level 2a at the point of which the elevator car 1 and the counterweight 3 are at essentially the same height, as already mentioned above. The balancing device 6 is arranged to extend, by the aid of its horizontal arm functioning as a lever-type transmission means 10, from the floor level 2a to inside the elevator car 1 via the open door opening 5 of the elevator car. The elevator car 1 is disposed with respect to the aforementioned floor level 2a preferably such that the floor le of the elevator car 1 is at essentially the same height as the floor of the floor level 2a. The force measuring means 12, e.g. a calibrating force sensor or corresponding device, of the balancing device 6 inside the elevator car 1 is configured to rest on the floor le of the elevator car 1, either directly or by the aid of some intermediate piece suited to the purpose.

The force measuring means 12 is fixed to the first end of the transmission means 10 by the aid of an intermediate means 11, such as a compression bar, transmitting compressive force, which intermediate means is fixed to the first end of the transmission means 10 via a hinge 11a. Correspondingly, a moving means 8, such as a trapezoidal screw, is fitted to the second end of the transmission means 10, which moving means rests at its bottom end on the floor of the aforementioned floor level 2a via a support member 7 and the top end of which moving means is a crank-type torsion means 9, with which the trapezoidal screw 8 is rotated around its essentially vertical center axis. The second end of the transmission means 10 is fitted onto the screw thread of the moving means 8 by the aid of a suitable intermediate piece such that when rotating the moving means 8 around its center axis the second end of the transmission means 10 either rises upwards along the trapezoidal screw or, depending on the rotation direction, also descends downwards along the trapezoidal screw.

The transmission means 10 is also fixed with a part between its first and second end at its fixing point 10a so as to be immovable at least upwards in the vertical direction. The fixing is implemented e.g. with a fixing means 13, the fixing arm 15 of which is hinged at its first end, e.g. in this case at its top end, to the fixing point 10a of the transmission means 10 and is rigidly fixed at its second end, e.g. in this case at its bottom end, to some supporting fixing point, such as e.g. to one or more walls of the elevator hoistway 2 below the elevator car 1. The fixing means 13 comprises e.g. a fixing arm 15 to be disposed in a vertical attitude between the sill of the elevator car 1 and the floor of the floor level 2a. The aforementioned fixing arm 15 is e.g. a flat bar, in the second end, i.e. the bottom end, of which is e.g. a suitably shaped aperture, from which the fixing arm 15 can be easily and quickly fixed in a hinged manner e.g. to a cotter bolt 9 installed in the wall on the door wall side of the elevator hoistway 2, the head of which cotter bolt, being larger than its stem part 19a, is configured to lock the bottom end of the fixing arm 15 onto the stem part 19a of the cotter bolt 19.

Figs. 2 and 3 present a magnified view of the second end, i.e. the bottom end, of the fixing arm 15. In Fig. 2 the bottom end of the fixing arm 15 is presented as viewed from the side and pulled upwards into its locking position and in Fig. 3 the bottom end of the fixing arm 15 is presented as viewed from the front. The aperture functioning as a fixing aid 20 in the bottom end of the fixing arm 15 is preferably of two parts in its size such that the first part, i.e. the upper part 21, _. of the aperture 20 is essentially round and larger in its diameter than the head of the cotter bolt 19 and correspondingly the second part, i.e. the lower part, of the aperture 20 forms an aperture 22 elongated in the longitudinal direction of the fixing arm 15, the first end of which aperture 22, i.e. the upper end, joins the upper part 21 and the second end, i.e. the lower end, is semicircular in shape. The second part 22 of the aperture 20 is larger in width than the stem part 19a of the cotter bolt 19 but smaller than the head of the cotter bolt 19. The fixing arm 15 is disposed onto the cotter bolt 19 via the first part 21 of the aperture 20 and is locked automatically by the aid of the second part 22 of the aperture 20 onto the stem part 19a of the cotter bolt 19 when the fixing arm 15 is pulled upwards into its operating position.

Fig. 4 presents a magnified side view of the second end of a balancing device 6 according to one second preferred embodiment to be used in the solution according to the invention. In this device 6 also a trapezoidal screw is used as a moving means 8, but now under the second end of the transmission means 10 is a movement screw 9a, which is rotated with a separate tool, such as with an open-ended wrench, for raising and lowering the second end of the transmission means 10 with the threads of the trapezoidal screw. In this way the moving means solution is slightly simpler than the first device solution presented above.

Figs. 5 and 6 present one second preferred solution according to the invention for balancing an elevator. In the solution according to Figs. 5 and 6, the fixing arm 15 is disposed in the elevator hoistway 2 between the elevator car 1 and the aforementioned floor level 2a on the door opening 5 side of the elevator car 1 and extends from the sill gap of the elevator car 1 from above the level of the floor le of the elevator car 1 past the sill of the elevator car and the floor of the floor level 2a to below the elevator car 1. Correspondingly, the fixing of the bottom end of the fixing arm 15 is implemented with friction pads 14 gripping the side walls of the elevator hoistway 2. The fixing means 13 comprises, in addition to the fixing arm 15, two leg parts

16 that are criss-crossed, connected to each other with a hinge 18, and of equal length, the length of which leg parts being adjustable. The total length of the leg parts 16 is adjusted such that the total length is always greater than the width of the elevator hoistway 2, and so that the hinge 18 settles in the width direction at the center of the elevator hoistway 2. On the free ends of the leg parts 16 are friction pads 14, which are fixed by the aid of a hinge

17 to the free ends of the leg parts 16. The second end, i.e. the bottom end, of the fixing arm 15 is fixed in a hinged manner to the shared hinge 18 of the leg parts 16.

The fixing means 13 is disposed below the elevator car 1 in the elevator hoistway 2 such that the leg parts 16 rest via the friction pads 14 on the side walls of the elevator hoistway 2. The fixing means 13 must be disposed so close to the sill level that the lever-type transmission means 10 of the balancing device 6 can be fixed to the top end of the fixing arm 15. In connection with installation of the fixing means 13, the fixing means 13 is pulled upwards in the direction of the arrow A to provide a suitable preset, by the aid of which adequate friction between the side walls of the elevator hoistway 2 and the friction pads 14 of the leg parts 16 is ensured, as is also the staying of the fixing means 13 in its position before the fixing of the fixing arm 15 to the transmission means 10 of the balancing device 6.

The fixing means 13 functions such that when pulling the fixing means 13 upwards by the fixing arm 15, the aforementioned pulling force and the friction force between the side walls of the elevator hoistway 2 and the friction pads 14 try to open the angle between the leg parts 16 and thus exert compressive force against the side walls of the elevator hoistway 2. The counterforce exerted by the side walls of the elevator hoistway 2 prevent, however, movement of the leg parts in the sideways direction, in which case the fixing means 13 stays in its position in the vertical direction from the effect of the forces exerted on the side walls and of the friction forces, and presses more strongly against the side walls the more it is tried to pull the fixing arm 15 upwards. Detachment of the leg parts 16 of the fixing means 13 occurs by lowering the fixing means downwards and by turning the leg parts 16 away from the side walls of the elevator hoistway 2.

Figs. 7 and 8 present a side view of a balancing device 6, producing the force needed for balancing an elevator, to be used in the solution according to the invention. In Fig. 7 the device is in its initial position and in Fig. 8 the balancing of the elevator is in its execution phase.

In the method and arrangement according to the invention the measuring of the balance of the elevator is implemented by driving the elevator car 1 first to a suitable floor level 2a e.g. to such a floor level 2a where the elevator car 1 and the counterweight 3 are at essentially the same height, as already mentioned above. After this the elevator is de- energized and the brake of the elevator is opened, after which the balancing device 6 is disposed in its position in the center of the elevator car 1 in the lateral direction of the elevator and the first end of the lever-type transmission means 10, with force measuring means 12, is disposed in the center of the elevator car 1. Correspondingly, the second end of the transmission means 10 is supported via a support member 7, or otherwise suitably, on the floor of the floor level 2a and the transmission means 10 is fixed with the fixing means 13 to its fixing point 10a to be immovable at least upwards in the vertical direction such that the transmission means 10 forms a rocker-like lever means, which can rotate in the vertical plane around the lever point formed by the fixing point 10a. The transmission means 10 preferably comprises a plurality of consecutive fixing points 10a in the longitudinal direction of the transmission means 10, so that the fixing point of the first end of the fixing arm 15 to the transmission means 10 can be adjusted in the longitudinal direction of the transmission means 10.

The fixing arm 15 of the fixing means 13 is preferably placed into its position e.g. by threading the bottom end of the fixing arm 15 into the elevator hoistway 2 from the sill gap of the elevator car 1 between the elevator car 1 and the floor of the floor level 2a to below the elevator car 1 and by fitting the aperture 20 in the bottom end of the fixing arm 15 onto the stem part 19a, of a cotter bolt 19 fixed in advance to the wall of the elevator hoistway 2 and by pulling the fixing arm 15 upwards, in which case the bottom end of the fixing arm 15 locks onto the stem part 19a of the cotter bolt 19. The fixing arm 15 is detached from the cotter bolt 19 by lowering it downwards and by pulling the bottom end of the fixing arm 15 off the end of the cotter bolt 19 via the first part 21 of the aperture 20.

When the balancing device 6 is ready in its position the measuring of the balance of the elevator is implemented by rotating the trapezoidal screw functioning as a moving means 8 around its center axis e.g. in the direction of the arrow B such that the second end of the transmission means 10 on the floor level 2a rises upwards in the direction of the arrow A, and since the transmission means 10 cannot rise upwards from its fixing point 10a, the first end of the transmission means 10 in the elevator car 1 and the force measuring means 12 on it, or the force sensor of it, presses downwards in the direction of the arrow C against the floor le of the elevator car 1, with a force that is measured with the force sensor that is a force measuring means 12 and which force is converted to correspond to a simulated load of the elevator car 1. The arrangement according to the invention comprises means for converting the measured force into a simulated load of the elevator car 1 in the units of weight desired, so that in this way the simulated load of the elevator car 1 can be ascertained e.g. in kilograms without needing to use cumbersome test weights.

In this way the extra load needed for e.g. the counterweight 3 can easily be ascertained. If, for example, a force sensor functioning as a force measuring means 12 in an elevator having a nominal load of 1000 kg shows when measuring the balance a reading of 500 kg, the counterweight 3 and the elevator car 1 are of the correct mutual weights when using a general 50% balance. If, on the other hand, the force sensor shows a reading of 300 kg, 200 kg must be added to the counterweight 3 when using the aforementioned 50% balance. If some other value for balance is used, e.g. 45% or 40%, the weights to be added must be calculated correspondingly .

Fig. 9 presents a simplified and diagrammatic view of one third preferred solution according to the invention for balancing an elevator. In this case the distribution of the floor levels 2a were not suited to the elevator car 1 and the counterweight 3 being at the same height exactly when the floor le of the elevator car 1 is at the same height as the floor of the floor level 2a. In practice the measurement accuracy is sufficient, even if in this case also the elevator car were lowered from a height midway between floor levels 2a to the height of the floor of the floor level 2a, in which case the counterweight 3 would rise a little higher. In addition the accuracy can be improved by taking the small weight difference of the hoisting ropes 4 into account, as already mentioned above.

If, however, it is desired to perform a precise measurement of the balance such that the elevator car 1 and the counterweight 3 are at the same height, the solution presented by Fig. 9 is suited to performing the task. In this case the force sensor functioning as a force measuring means 12 is disposed on the second end of the lever-type transmission means 10 and to rest on the floor of the floor level 2a. The balancing device 6 is fixed to the elevator hoistway 2 with a fixing means 13, as in the solutions described above, and a moving means 8, such as a trapezoidal screw or corresponding means, is fixed to the first end of the transmission means 10 below the elevator car 1 to pull the elevator car 1 downwards. In this case the top end of the moving means 8 is fixed to the car sling la of the elevator car 1 below the elevator car and the bottom end of the moving means 8 is configured to move the first end of the transmission means 10 up and down by the aid of the movement screw 9a, which is disposed on the trapezoidal screw below the first end of the transmission means 10. The movement screw 9a is rotated e.g. with a separate tool, such as with an open-ended wrench.

If in the case according to Fig. 9 it were desired to dispose the balancing device 6 on the higher floor level 2a visible in Fig. 9, e.g. the balancing device 6 presented in Fig. 1 could be used such that one or more intermediate pieces of a suitable height would be placed between the force sensor functioning as a force measuring means 12 and the floor le of the elevator car 1, or the length of the intermediate means 11 that is the fixing means of the force measuring means 12 would be increased. An intermediate means 11 can be e.g. adjustable in length or the intermediate means can be of different lengths.

It is obvious to the person skilled in the art that the invention is not limited solely to the examples described above, but that it may be varied within the scope of the claims presented below. Thus, for example, the structure of the balancing device may differ from what is presented above. For example, the moving of the second end of the transmission means can be done with other actuators than a trapezoidal screw, e.g. with a hydraulic jack. It is also obvious to a person skilled in the art that instead of force sensor, e.g. a mechanical weighing appliance can be used, which is configured to function as a sufficiently accurate measuring means.

Claims

1. Method for measuring the balance of an elevator in an elevator, in which method an elevator car (1) provided with one or more counterweights (3) is stopped at a desired point in the elevator hoistway (2) and at least the brake of the elevator is opened, characterized in that for measuring the balance of the elevator a force directed downwards is exerted on the elevator car (1) with a separate balancing device (6) , the magnitude of which force is measured with a force measuring means (12) .

2. Method according to claim 1, characterized in that the measured force is converted into a simulated load of the elevator car (1) in the units of weight desired.

3. Method according to claim 1 or 2, characterized in that the balancing device (6) is disposed from the open door (5) of the elevator car (1) partly inside the elevator car (1) such that the first end of the balancing device (6) is configured to rest on the floor (le) of the elevator car (1) and the second end of the balancing device (6) is configured to rest on the floor of the floor level (2a) , and in that the balancing device (6) is fixed by the part of it between the first end and the second end to become a rocking lever structure that is immovable at least upwards, when the second end of which lever structure is moved upwards the first end with the force measuring means (12) presses against the floor (le) of the elevator car (1) .

4. Method according to claim 1 or 2, characterized in that the balancing device (6) is disposed partly below the elevator car (1) such that the first end of the balancing device (6) with its moving means (8) is configured to rest on the structures of the bottom part of the elevator car (1) and the second end of the balancing device (6), with force measuring means (12), is configured to rest on the floor of the floor level (2a), and in that the balancing device (6) is fixed by the part of it between the first end and the second end to become a rocking lever structure that is immovable at least upwards, when the first end of which lever structure is moved upwards the second end with the force measuring means (12) presses against the floor of the floor level (2a) .

5. Method according to any of the preceding claims, characterized in that the balancing device (6) is fixed into its position on the wall of the elevator hoistway (2) via a fixing means (13) fixed immovably at least in the vertical direction from a hinged fixing point (10a) between the first end and the second end of the balancing device (6) .

6. Method according to any of the preceding claims, characterized in that the fixing means (13) is fixed to the wall of the elevator hoistway (2) so as to be immovable upwards, by the aid of a fixing means (19) to be fixed to the wall of the elevator hoistway (2), such as e.g. by the aid of a cotter bolt, by threading the fixing arm (15) of the fixing means (13) into the elevator hoistway (2) from the sill gap between the elevator car (1) and the floor level (2a) to below the elevator car (1) and by fixing the bottom end of the fixing arm (15) to the fixing means (19) .

7. Method according to any of the preceding claims 1-5, characterized in that the fixing means (13) is fixed to the wall of the elevator hoistway (2) so as to be immovable upwards via leg parts (16) connected crosswise to each other with a hinge (18) and via friction pads (14) resting on the wall of the elevator hoistway (2) on the free ends of the leg parts (16) .

8. Method according to any of the preceding claims, characterized in that the end connected to the moving means (8) of the transmission means (10) of the balancing device (6) is moved, when performing the measurement of balance, upwards by the aid of a moving means (8), such as a trapezoidal screw or corresponding means.

9. Arrangement for measuring the balance of an elevator, which comprises at least an elevator car (1) configured to move in an elevator hoistway (2) , which elevator car is connected via hoisting ropes (4) to one or more counterweights (3) , characterized in that the arrangement for measuring the balance of an elevator comprises a separate balancing device (6), comprising means (7-13) for exerting a force directed downwards on the elevator car (1) and for measuring the magnitude of the aforementioned force.

-10. Arrangement according to claim 9, characterized in that the arrangement comprises means for converting the measured force into a simulated load of the elevator car (1) in the units of weight desired.

11. Arrangement according to claim 9 or 10, characterized in that the balancing device (6) is configured to be disposed from the open door (5) of the elevator car (1) partly inside the elevator car (1) such that the first end of the balancing device (6) rests on the floor (le) of the elevator car (1) and the second end of the balancing device (6) rests on the floor of the floor level (2a) , and in that the balancing device (6) is fixed by the part of it between the first end and the second end to become a rocking lever structure that is immovable at least upwards, when the second end of which lever structure is moved upwards the first end with the force measuring means (12) presses downwards against the floor (le) of the elevator car (1) .

12. Arrangement according to claim 9 or 10, characterized in that the balancing device (6) is disposed partly below the elevator car (1) such that the first end of the balancing device (6) with its moving means (8) is configured to rest on the structures of the bottom part of the elevator car (1) and the second end of the balancing device (6), with force measuring means (12) , is configured to rest on the floor of the floor level (2a) , and in that the balancing device (6) is fixed by the part of it between the first end and the second end to become a rocking lever structure that is immovable at least upwards, when the first end of which lever structure is moved upwards the second end with the force measuring means (12) presses against the floor of the floor level (2a) .

13. Arrangement according to any of the preceding claims 9-

12, characterized in that the arrangement comprises a fixing means (13) configured to be fixed immovably at least in the vertical direction to the wall of the elevator hoistway (2), to which fixing means the balancing device (6) is configured to be fixed in a hinged manner from its fixing point (10a) between the first end and the second end.

14. Arrangement according to any of the preceding claims 9-

13, characterized in that the fixing means (13) comprises an essentially vertical fixing arm (15), on the second end of which is a fixing aid (20) , such as an aperture, from which the fixing means (13) is configured to be fixed to the wall of the elevator hoistway (2) so as to be immovable, by the aid of a fixing means (19), such as e.g. a cotter bolt, to be fixed to the wall of the elevator hoistway (2) .

15. Arrangement according to any of the preceding claims 9- 13, characterized in that the fixing means (13) comprises an essentially vertical fixing arm (15) , and leg parts (16) connected with a hinge (18) to the second end of the fixing arm (15) and crosswise to each other, as well as friction pads (14) fixed by the aid of a hinge on the free ends of the leg parts (16) , which friction pads are configured to rest on the wall of the elevator hoistway (2) when pulling the fixing arm (15) upwards.

16. Arrangement according to any of the preceding claims 9- 15, characterized in that on the second end of the balancing device (6) on the floor level (2a) ^' is a moving means (8), such as a trapezoidal screw, resting on the floor of the floor level (2a) , for moving the second end of the transmission means (10) of the balancing device (6) upwards when ^"performing a measurement of the balance of an elevator.

17. Arrangement according to any of the preceding claims 9- 15, characterized in that on the first end of the balancing device (6) connected to the structures of the elevator car (1) is a moving means (8) , such as a trapezoidal screw, for moving the first end of the transmission means (10) of the balancing device (6) upwards when performing a measurement of the balance of an elevator.

18. Arrangement according to any of the preceding claims 9-

17, characterized in that the arrangement comprises one or more ballast weights, which can be added to the counterweight and/or to the elevator car.

19. Arrangement according to any of the preceding claims 9-

18, characterized in that the arrangement comprises one or more ballast weights, which can be removed from the counterweight and/or from the elevator car.

20. Method for balancing an elevator, characterized in that a support force resisting upward movement of the elevator car is exerted on the elevator car, the brake or the brakes of the elevator and the elevator machine are released from acting on the movement of the elevator, the support force is measured and the balance is changed such that the support force changes towards the value according to the desired balance .

21. Method according to claim 20, characterized in that the balance is changed by adding to the counterweight and/or to the elevator car one or more separate ballast weights. 22. Method according to any of the preceding claims 20 or 21, characterized in that the balance is changed by removing from the counterweight and/or from the elevator car one or more separate ballast weights.

22. Method according to any of the preceding claims 20, or 21, characterized in that in connection with the balancing the balance of the elevator is measured using a method according to any of the preceding claims 1-8.