Method for operating an elevator system, computer equipment

Abstract

Method for operating an elevator system (1) with traction sheave drive, wherein the elevator system (1) comprises at least one traction sheave (2), a suspension rope (3) guided over the traction sheave (2), a car (4) and a counterweight (5) connected to the car (4) by means of the suspension rope (3), characterized in that: - in downward travel and / or upward travel at least one or each acceleration (ẍ) of the car (4) and / or the counterweight (5) is detected, and - depending on the acceleration (ẍ), a mass ratio (V) of car mass (P) to counterweight mass (G) and / or a load balance (L) of the elevator system (1) is determined, and - in determining the mass ratio (V) and / or load balance (L), a compensation factor (k) for a frictional force arising during acceleration due to slippage of the suspension rope (3) on the traction sheave (2) is taken into account, wherein the Compensation factor (k) is a rational number k = 2.

Description

The invention relates to a method for operating an elevator installation with traction sheave drive, wherein the elevator installation has at least one traction sheave, a carrying cable guided over the traction sheave, a car and a counterweight connected to the car by means of the carrying cable.The invention also relates to a computer device which is specially designed to carry out the method according to the invention.From the prior art, elevator installations of the type mentioned at the beginning are mentioned. Such elevator installations are usually checked for their operational reliability at regular intervals. For example, a drivability of the traction sheave is determined for this purpose and it is checked whether this is sufficient. Thus, for example, from the patent specification DE 10 2006 042 909 B4 of the applicant, a method for testing the driving capability in such elevator installations is known, wherein the driving capability is judged to be sufficient, and the elevator installation passes the test if a predefined test condition is fulfilled. It is provided that the traction sheave is decelerated upward during the rapid travel of the elevator car, and that a maximum braking acceleration occurring during deceleration on counterweight, elevator car and / or carrying cable is detected. For the formula disclosed therein for determining the driving capability by means of deceleration measurement, the masses of counterweight and car are required. Specifically, the test condition used includes a mass ratio of car mass to counterweight mass. These masses are usually determined by complex measurements by means of corresponding weighing devices.Laid-open specification CN 1 03 145 015 A discloses a method for operating a lift installation, in which a lift cage mass and / or a counterweight mass are determined when the brake is open as a function of a time duration until a predefined acceleration is reached. Further methods for operating elevator installations are known from the published patent applications CN 1 05 905 724 A, DE 10 2009 026 992 A1 and DE 10 2014 101 381 A1 and from the patent specification EP 3 848 314 B1.The object of the invention is to provide an alternative, improved method for determining measured variables, in particular the mass ratio mentioned above, which are usually recorded during the testing of elevator installations and which is carried out with reduced measurement and calculation effort.The object on which the invention is based is achieved by a method having the features of claim 1. According to the invention, it is provided here that at least one or in each case one acceleration of the elevator car and / or of the counterweight is detected in downward travel and / or upward travel, and that a mass ratio of elevator car mass to counterweight mass and / or a load compensation of the elevator installation is determined as a function of the acceleration. This creates a particularly advantageous possibility for ascertaining the mass ratio mentioned at the beginning and a load compensation likewise normally ascertained during the testing of elevator installations, in which, in contrast to the methods mentioned at the beginning, a complex measurement of the car mass and the counterweight mass is dispensed with. The method according to the invention thus greatly reduces the testing effort. The invention is thus based on the finding that the mass ratio is alternatively advantageously determined simply by acceleration measurement or deceleration measurement.According to the invention, it is provided that in the determination of mass ratio and / or load compensation, a compensation factor for a frictional force arising during the acceleration due to slipping of the supporting cable on the traction sheave is taken into account, wherein the compensation factor k is a rational number k=2. The compensation factor results in the advantage that the precise effect of the frictional force does not have to be determined in a complicated manner, but is replaced by a sufficiently precise estimation with little effort.It is particularly preferably provided that a number of the load-bearing ropes is taken into account as suspension divider of the elevator installation when determining mass ratio and / or load compensation, wherein the suspension divider is a natural number. This advantageously ensures that reliable results are produced by the method independently of the design of the elevator installation. The suspension divider thus denotes the type of pulley block arrangement used. If the supporting cable is merely guided over the traction sheave, the suspension divider is 1. For each pulley over which the supporting cable is guided, the suspension divider increases by 1. and in the case of an additional pulley it is 2.According to a preferred development of the invention, it is provided that the arithmetic mean of the detected accelerations is taken into account in the determination of mass ratio and / or load compensation. If a plurality of accelerations are detected, for example in each case in upward and downward travel, and / or at the car and counterweight, the calculation of the arithmetic mean results in the advantage that the accuracy of the determination of mass ratio and / or load compensation is further improved. A sum of two detected accelerations (for example, upward and downward travel) is halved insofar as a sum of four detected accelerations (for example, upward and downward travel, in each case at car and counterweight) is quartered.It is particularly preferably provided that the traction sheave is driven in order to move the elevator car in a first direction of travel, in particular downwards, that the traction sheave is decelerated, in particular with a predetermined braking force, and that at least a first deceleration is detected as acceleration. By detecting a corresponding first deceleration in the first direction of travel, it is advantageously ensured that mass ratio and / or load compensation are determined particularly easily.According to a preferred development of the invention, it is provided that the traction sheave is driven in order to move the elevator car in a second direction of travel, in particular upwards, opposite to the first direction of travel, that the traction sheave is decelerated, in particular with the predetermined braking force, and that at least one second deceleration is detected as acceleration. The additional detection of the corresponding second deceleration in the second direction of travel results in the advantage that the accuracy of the determination of mass ratio and / or load compensation is further improved.It is particularly preferably provided that a height position of the elevator car in its elevator car shaft is predefined as a function of an expected mass ratio, in particular to two thirds of a total height of the elevator car shaft, and that the traction sheave is decelerated at the predefined height position. This advantageously ensures that an influence of the cable mass of the supporting cable on the result is minimized. The height position is calculated in particular as the product of the mass ratio and the maximum displacement height of the car.According to a preferred development of the invention, it is provided that, in order to detect the acceleration from a static state of the elevator installation, a brake device assigned to the traction sheave is released, so that the elevator car is moved free of drive. This results in the advantage that the determination of mass ratio and / or load compensation is particularly simple, because driving and deceleration of the drive pulley is dispensed with.It is particularly preferably provided that the mass ratio is determined by the equation and / or the load compensation is determined by the equation, wherein k=compensation factor for frictional force, ẍ=determined acceleration, b=number of accelerations, g=eceed acceleration, and D= suspension divider. This creates a particularly advantageously simple possibility for ascertaining mass ratio and / or load compensation.According to a preferred development of the invention, it is provided that a driving capability of the traction sheave is determined as a function of the mass ratio determined, in particular in upward travel according to the equation wherein g=ecew acceleration, and ẍ=e determined acceleration. This results in the advantage that the initially mentioned determination of the drivability is carried out particularly easily without knowledge of the actual masses. The acceleration is or comprises in particular one of the above-mentioned detected decelerations in upward travel.It is particularly preferably provided that a contact mass of the counterweight is detected, that a cable mass of the carrying cable is determined, and that the car mass and / or the counterweight mass are determined as a function of the determined mass ratio, the cable mass and the contact mass. This creates a particularly advantageously simple possibility of comparing the masses with their desired values without actually measuring the masses directly.According to a preferred development of the invention, it is provided that the cable mass is determined according to the equation S=h F×n×m S and that the car mass is determined according to the equation and / or the counterweight mass is determined according to the equation, wherein h is F= displacement height, n=ceed number, and m is S= specific cable weight. This creates a particularly advantageously simple possibility for ascertaining the masses. Specifically, the rope number n corresponds to the product of the suspension divider D and the number of the support ropes used. The delivery height refers in particular to a maximum possible height position of the elevator car in its elevator car shaft.It is particularly preferably provided that a height position of the elevator car in its elevator car shaft is predefined as a function of an expected mass ratio, in particular over two thirds of a total height of the elevator car shaft, and that a correction value for the elevator car mass and / or the counterweight mass is determined as a function of a deviation from the height position. The correction value advantageously ensures that an influence of the cable mass of the supporting cable on the result is at least largely eliminated.According to a preferred development of the invention, it is provided that an actual height position is detected, that the correction value is determined according to the equation, wherein n=ceeds number, and m is S= specific rope weight, and that the correction value is added to the car mass and / or subtracted from the counterweight mass. This creates a particularly advantageously simple possibility for ascertaining the corrected masses.The computer device having the features of claim 15 is characterized in that it is specifically designed to carry out the method according to the invention. This also results in the advantages already mentioned.Further advantages and preferred features and combinations of features emerge in particular from the description above and from the claims. The invention will be explained in more detail below with reference to the drawings. This is shown by FIG. 1 shows an elevator installation, and FIG. 2 shows an advantageous method for operating the elevator installation.FIG. 1 shows a schematic illustration of an elevator installation 1 with a traction sheave drive. The elevator installation 1 has at least one drivable traction sheave 2, a carrying cable 3 guided over the traction sheave 2, a car 4 and a counterweight 5 connected to the car 4 by means of the carrying cable 3.The traction sheave 2 is assigned an actuatable brake device 6 for applying a predetermined braking force to the traction sheave 2 and thus for decelerating the traction sheave 2 in order to brake the elevator car 4 and the counterweight 5 and to maintain them in a predetermined position.In the present case, the elevator installation 1 is further assigned a computer device 7, for example as part of an external checking device for the elevator installation 1. A sensor arrangement 8 is connected to the computer device 7 in terms of communication technology, which sensor arrangement has, for example, an acceleration sensor and is designed to detect an acceleration ẍ, in particular deceleration, of the elevator car 4 and / or of the counterweight 5.The car 4 has a car mass P (empty mass) and the counterweight 5 has a counterweight mass G, wherein the counterweight mass G is usually greater than the car mass P by a predefined differential mass ΔG, for example half the payload, as indicated by a separation. Thus, G=P+ΔGIf, starting from a static case in which the traction sheave 2 is blocked by the brake device 6 assigned to it, so that the car 4 and counterweight 5 are stationary, the brake device 6 is released (the brake is opened), the force resulting from the product of the differential mass ΔG of counterweight mass G and car mass P and the acceleration due to gravity (i.e. the known formula F=m×a) accelerates the compensated total elevator masses which consist of the counterweight mass G and the car mass P. The acceleration ẍ that arises can be detected by means of the sensor arrangement 8.In the following, with reference to FIG. 2, an advantageous method for operating the elevator installation 1 is described. For this purpose, FIG. 2 shows the method on the basis of a flow chart. In particular, the method ensures that the elevator installation is tested at low cost. The method is carried out in particular with the aid of the computer device 7 and the sensor arrangement 8.The method is particularly advantageous if, as mentioned at the beginning, a driving capability T of the elevator installation 1 is to be determined. For the determination and testing of the drivability T according to the applicant's patent mentioned at the beginning by means of deceleration measurement, counterweight mass G and car mass P are required, as can be seen in the following equation:The invention is based on the finding that the mass ratio is alternatively advantageously determined simply by acceleration measurement or deceleration measurement. It is thus not necessary to know the exact masses, so that in particular a complicated weighing of counterweight and cab is dispensed with.The method begins with a step S 1, in which at least one or respectively one acceleration ẍ of the car 4 and / or of the counterweight 5 is detected during downward travel and / or upward travel.In a first, simplest variant, the brake device 6 assigned to the traction sheave 2 is released to detect the acceleration ẍ from a static state of the elevator installation 1, so that the elevator car 4 is moved free of drive, as described above by way of example for FIG. 1.Depending on a current height position of the car 4, the differential mass ΔG, and a rope mass S of the carrying rope 3, the car 4 is accelerated upward or downward. The acceleration ẍ generated by the imbalance of the masses when the brake is open and without drive, which acceleration is, for example, an acceleration ẍ P,ab of the car mass P in the downward direction, can be expressed by the following equation, starting from the generally known formula for this acceleration case:The acceleration is thus dependent only on the constant gravitational acceleration g and also counterweight mass G and car mass P.If the elevator installation 1 has further deflection rollers in addition to the drive pulley 2 shown in FIG. 1, i.e. if it is suspended for example in the manner of a pulley block 2:1 or similar, the sum of the two masses G and P in the denominator must be divided into (G+P) / D according to a ratio designated in the present case as suspension divider D. For example, the suspension divider D has the value 2 in case 2:1, the value 4 in case 4:1, etc. The suspension divider D enters the equation as follows by simplifying the equation in which the suspension divider D is moved to the counter:In order to minimize influences of friction, mass inertia of the traction sheave and drive shaft, etc., it is advantageous if the measurement of the acceleration ẍ or deceleration takes place directly in the elevator car shaft. Preferably, the brakes are not held open, but braking force, inertia, etc. are calculated by equivalent braking in upward and downward directions. For this purpose, car 4 and counterweight 5 must be in motion beforehand.In a second variant, therefore, the traction sheave 2 is driven in order to move the elevator car 4 in a first direction of travel, downward or upward. Subsequently, the traction sheave 2 is decelerated by the brake device 6, in the present case with a predetermined braking force. Finally, at least a first, in particular maximum, deceleration is detected as acceleration ẍ, namely a deceleration ẍ P,ab of the car mass P in downward travel, a deceleration ẍ P,auf of the car mass P in upward travel, a deceleration ẍ G,ab of the counterweight mass G in downward travel, and / or a deceleration ẍ G,auf of the counterweight mass G in upward travel.For example, only the car mass P is considered and first the deceleration ẍ P,ab of the car mass P in the downward travel is detected. Alternatively, only the counterweight mass G is considered and a deceleration ẍ G,ab of the counterweight mass G in downward travel is detected.Now, the traction sheave 2 is driven to move the car 4 in a second direction of travel opposite to the first direction of travel, downward or upward. Subsequently, the traction sheave 2, in the present case again with the same predetermined braking force, is decelerated. Finally, at least one second, in particular maximum deceleration, selected from the decelerations described above is detected as acceleration ẍ.For example, only the car mass P is considered, and in addition to the deceleration ẍ P,ab of the car mass P in downward travel, the deceleration ẍ P,auf of the car mass P in upward travel is detected. Alternatively, only the counterweight mass G is considered, and in addition to the deceleration ẍ G,ab of the counterweight mass G in downward travel, the deceleration ẍ G,auf of the counterweight mass G in upward travel is detected.Preferably, in each case a height position h of the elevator car 4 in its elevator car shaft is predefined as a function of an expected mass ratio V, which is predefined for example by the manufacturer, in particular to two thirds of a total height of the elevator car shaft, and the traction sheave 2 is respectively decelerated at the predefined height position h. Thus, an influence of the rope mass of the support rope 3 is minimized.Thus, in each case a journey in the upward direction is braked and a journey in the downward direction is decelerated with the same brake application, and the decelerations are measured, wherein the static forces nevertheless act, so that the relationships described for variant 1 basically continue to apply. In the present case, an average value of the detected accelerations ẍ is then formed in order to be able to use it in the aforementioned equation.It should be noted that, not explicitly detected, braking accelerations ẍ Brems dependent on the braking force act on counterweight mass G and car mass P, which have to be added, namely a braking acceleration ẍG,up,braking on the counterweight mass G in upward travel, a braking acceleration ẍ G,ab,Brems on the counterweight mass G in downward travel, a braking acceleration ẍP,up,braking on the car mass P in upward travel and a braking acceleration ẍ p,ab,Brems on the car mass in downward travel.However, since, as described above, the same braking forces act in each case, the corresponding braking accelerations cancel one another out, since the braking force acts in the positive direction, i.e. in the direction of gravitational acceleration, during the upward travel, and in the negative direction, i.e. counter to gravitational acceleration, during the downward travel, so that the signs of the braking decelerations are opposite and balance one another in sum.Thus, if the car mass P is considered exclusively, the following equation is obtained:When only considering the counterweight mass G, the following equation is obtained:In a third variant, which builds on the second variant, both the aforementioned accelerations ẍ at the car mass P and the accelerations ẍ at the counterweight mass G are detected. As a result, spring-damper effects on both sides are averaged and the accuracy of the result is further improved. The equation is obtained:If the above-mentioned detection of the acceleration or accelerations ẍ is complete, the method is continued with a step S 2. In step S 2, the mass ratio V of car mass P to counterweight mass G and / or a load compensation L of the elevator installation 1 already discussed above is determined as a function of the detected acceleration or accelerations ẍ.Mathematically, this determination is limited to a conversion of the above-mentioned equations resolved according to acceleration ẍ to G / P, which corresponds to mass ratio V. In this respect, as described above, a number of the load-bearing ropes is taken into account as suspension divider D of the elevator installation 1 in the determination, wherein the suspension divider D is a natural number. In addition, as far as a plurality of accelerations ẍ have been detected, the arithmetic mean of the detected accelerations ẍ is taken into account, so that the underlying equation looks like the following in general form:However, in dynamic measurements, further forces occur when the support cable 3 slips during the deceleration and overcomes the static friction. Then, at the time of slipping, an add-on force F Z, which must be added to the term (G - P) × g × D in the counter, acts. In the extreme case, the additional force F corresponds to Z= G×g.The actual amount of the additional force F Z is unknown and largely depends on the friction coefficients for static friction and clamping friction and the portion of the slide time on the total braking time. This can be determined only very laboriously.In the present case, therefore, a compensation factor k for a frictional force arising during the acceleration due to slipping of the supporting cable 3 on the traction sheave 2 is taken into account in the ascertainment of mass ratio V and / or load compensation L, wherein the compensation factor k is in particular a rational number k>1, k=2 or k>2. The compensation factor k is chosen to compensate for the effective additional force F Z. It has been found that a sufficiently accurate estimate is achieved if the mass G+P to be decelerated, which corresponds to the denominator, is replaced by a product of compensation factor k and car mass P. The equation is then:It could be determined by practical tests that the effective additional force F Z is compensated on average, in particular when the mass G+P to be decelerated in the denominator is reduced by the differential mass G-P, so that the following applies: G+P-(G-P)=2×P. If transmitted in the general case, this means that k=2. This is a mean value which is generally sufficiently accurate, in particular when the drive is not energized and the recuperation is switched off. In principle, between complete slipping, which corresponds to approximately 1×P, and no slipping, which, depending on the design, usually corresponds to approximately 2.3×P to 2.8×P (G+P), any value in the denominator can be established as the effective mass to be delayed.Solving the above equation for the mass ratio V yields:By way of example, variant 3 yields when k=2 is assumed:The first term on the right side corresponds to the so-called load compensation L, which corresponds to the mass component by which the counterweight 5 is relatively heavier than the car 4, and which is thus calculated according to the following equation:This results in variant 3 and k=2:By calculating the load compensation L in this way, it can be determined in a simple manner during a check of the elevator installation 1 whether the elevator car mass P and / or the counterweight mass G have been modified or manipulated in an unauthorized manner.After mass ratio V and / or load compensation L has been determined, the method can be ended with step S 6.Alternatively, if the mass ratio V is determined, in an optionally following step S 3 a drivability T of the traction sheave 2 is determined as a function of the determined mass ratio V, in particular in upward travel according to the equation known from the initially mentioned patent of the applicant: Again alternatively or additionally, in particular in parallel, in an optionally following step S 4 a contact mass A of the counterweight 5 is detected, a cable mass S of the carrying cable 3 is determined, and the actual car mass P and / or the counterweight mass G is determined as a function of the determined mass ratio V, the cable mass S and the contact mass A.The placement mass A is placed by placing the counterweight 5 on a corresponding weighing device, for example as part of the sensor arrangement 8, wherein a drive assigned to the traction sheave 2 is neutral and the brakes of the brake device 6 are open. The contact mass A corresponds to the sum of the cable mass S and a so-called half load H, i.e. a mass difference between the counterweight mass G and the car mass P. The following applies:By replacing the counterweight mass G with the product of the mass ratio V and the car mass P (V=G / P, accordingly, G=V×P) holds:Resolved according to the car mass P, the equation is given:The counterweight mass G is obtained according to the equation:The rope mass S can be determined from a product of a displacement h F, a rope count n and a specific rope weight m SThus, both car mass P and counterweight mass G can be advantageously determined simply, with knowledge of mass ratio V, placement mass A, which is easier to determine by measurement technology, and rope mass S. The method can now be ended with step S 6.Preferably, however, in a subsequent optional step S 5, the aforementioned height position h is predefined as a function of the expected mass ratio, and a correction value Δm for the car mass P and the counterweight mass G is determined as a function of a deviation from the height position h.For this purpose, an actual height position h ist is detected, and the correction value is determined according to the following equation:Finally, the correction value is added to the car mass P and subtracted from the counterweight mass G, so that a corrected car mass P korr and a corrected counterweight mass G korr are determined:The method is now ended with step S 6.LIST OF REFERENCE CHARACTERS1 Lift installation 2 Traction sheave 3 Carrying cable 4 Lift cage 5 Counterweight 6 Braking device 7 Computer device 8 Sensor arrangement ΔG Differential mass Δm Correction value for masses A Placement mass b Number of accelerations D Suspension divider F Z Additional force g Gravitational acceleration G Counterweight mass G korr Corrected counterweight mass H Half load h Predefined height position h F Delivery height h ist Actual height position k Compensation factor L Load compensation m S Specific cable weight n Cable number P Lift cage mass P korr Corrected lift cage mass S Cable mass T Traction capability V Mass ratio of lift cage mass to counterweight mass ẍ acceleration ẍ Brems braking acceleration ẍ G,ab deceleration of the counterweight in downward travel ẍ G,ab,Brems braking acceleration of the counterweight in downward travel ẍ G,auf deceleration of the counterweight in upward travel ẍG,auf,BremsBremsbeschleunigung of the counterweight in upward travel ẍ P,ab deceleration of the car in downward travel ẍ P,ab,Brems braking acceleration of the car in downward travel ẍ P,auf deceleration of the car in upward travel ẍP,auf,BremsBremsbeschleunigung of the car in upward travel

Claims

Method for operating an elevator installation (1) with traction sheave drive, wherein the elevator installation (1) has at least one traction sheave (2), a carrying cable (3) guided over the traction sheave (2), a car (4) and a counterweight (5) connected to the car (4) by means of the carrying cable (3), characterized - in that at least one or in each case an acceleration (ẍ) of the car (4) and / or of the counterweight (5) is detected in downward travel and / or upward travel, and - in that a mass ratio (V) of car mass (P) to counterweight mass (G) and / or a load compensation (L) of the elevator installation (1) is determined as a function of the acceleration (ẍ), and - that in the determination of mass ratio (V) and / or load compensation (L) a compensation factor (k) for a frictional force arising during acceleration due to slipping of the supporting cable (3) on the traction sheave (2) is taken into account, wherein the compensation factor (k) is a rational number k=2.Method according to Claim 1, characterized in that a number of the load-bearing ropes is taken into account as suspension divider (D) of the elevator installation (1) in the determination of mass ratio (V) and / or load compensation (L), wherein the suspension divider (D) is a natural number.Method according to one of the preceding claims, characterized in that the arithmetic mean of the detected accelerations (ẍ) is taken into account in the determination of mass ratio (V) and / or load compensation (L).Method according to one of the preceding claims, characterized in that the traction sheave (2) is driven in order to move the elevator car (4) in a first direction of travel, in particular downwards, in that the traction sheave (2) is decelerated, in particular with a predefined braking force, and in that at least one first deceleration (ẍ P,ab, ẍ P,auf, ẍ G,ab, ẍ G,auf) is detected as acceleration (ẍ).Method according to Claim 4, characterized in that the traction sheave (2) is driven in order to move the elevator car (4) in a second direction of travel, in particular upwards, which is opposite to the first direction of travel, in that the traction sheave (2) is decelerated, in particular with the predefined braking force, and in that at least one second deceleration (ẍ P,ab, ẍ P,auf, ẍ G,ab, ẍ G,auf) is detected as acceleration (ẍ).Method according to one of Claims 4 and 5, characterized in that a height position (h) of the car (4) in its car shaft is predefined as a function of an expected mass ratio (V), in particular to two thirds of a total height of the car shaft, and in that the traction sheave (2) is decelerated at the predefined height position (h).Method according to one of Claims 1 to 3, characterized in that, in order to detect the acceleration (ẍ) from a static state of the elevator installation (1), a brake device (6) assigned to the traction sheave (2) is released, with the result that the elevator car (4) is moved in a drive-free manner.Method according to one of the preceding claims, characterized in that the mass ratio (V) is determined by the equation V = k × ∑ i = 1 b x%0020̈ i b g × D + 1 and / or the load compensation (L) is determined by the equation L = k × ∑ i = 1 b x%0020̈ i b g × D wherein k = compensation factor for frictional force, ẍ = determined acceleration, b = number of accelerations, g = gravitational acceleration, and D = suspension divider.Method according to one of the preceding claims, characterized in that a driving capability (T) of the traction sheave (2) is determined as a function of the mass ratio (V) determined, in particular in upward travel according to the equation T = V × g + x%0020̈ g - x%0020̈ wherein g = gravitational acceleration, and ẍ = determined acceleration.Method according to one of the preceding claims, characterized in that a ground mass (A) of the counterweight (5) is detected, in that a cable mass (S) of the carrying cable (3) is determined, and in that the car mass (P) and / or the counterweight mass (G) are determined as a function of the determined mass ratio (V), the cable mass (S) and the ground mass (A).Method according to Claim 10, characterized in that the cable mass (S) is determined according to the equation S = h F × n × m S and in that the car mass (P) is determined according to the equation P = A - S V - 1 and / or the counterweight mass (G) is determined according to the equation G = V × P = V × A - S V - 1 where h F= is the delivery height, n = the number of cables, and m S= is the specific cable weight.Method according to one of Claims 10 and 11, characterized in that a height position (h) of the car (4) in its car shaft is predefined as a function of an expected mass ratio, in particular to two thirds of a total height of the car shaft, and in that a correction value (Δm) for the car mass (P) and / or the counterweight mass (G) is determined as a function of a deviation from the height position (h).Method according to claim 12, characterised in that an actual height position (h ist) is detected, that the correction value is determined according to the equation Δ m = ( h V + 1 - h i s t ) × n × m S where n = rope number, and m S= is specific rope weight, and that the correction value (Δm) is added to the car mass (P) and / or subtracted from the counterweight mass (G).Computer device (7), characterized in that the computer device (7) is specifically designed to carry out the method according to one of the preceding claims.

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