JP2000238969A - Balance point adjusting method for elevator car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a balance point adjusting method for an elevator car where an accurate balance point is calculated using a light load reducing labor and work time of workers, and amount of balance weight to be loaded/unloaded according to this can be determined. SOLUTION: When a brake of a motor is released, stationary torques 20a-20c for stopping a motor rotating force caused by load difference between a car and balance weight and starting torques 21a-21c for rotating the motor oppositely to the rotating direction of the motor are measured in an unload state or a light load state of a car 1, an unbalance load 23 is calculated from their average approximation line 22, a balance point is calculated from this unbalance load 23, and the balance weight required for providing a prescribed balance point is adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevator car balance point adjusting method for calculating a balance point of an elevator car and adjusting a counterweight according to the calculated balance point.

[0002]

2. Description of the Related Art Generally, an elevator will be described with reference to the schematic configuration diagram of FIG. 4, in which a brake 15, a traction machine 11, and a sheave 4 are respectively connected to a rotating shaft 12a of a motor 12, and a rope 3 wound around the sheave 4. When the rotating shaft 12a of the motor 12 is rotated by a command from a control panel (not shown), the sheave 4 is rotated via the traction machine 11, and the sheave 4 is rotated. The car 1 is raised or lowered by friction between the car 1 and the rope 3, and after the car 1 is stopped, the rotation of the motor shaft 12a is fixed by the brake 15 and the state is maintained.

The balance point of the weight 13 which is balanced with the car 1 is connected so that the current value of the motor 12 is measured by the ammeter 6, and rises and falls in a state where a load of about half of the maximum load is applied to the car 1. The motor 12 driving the sheave 4 is adjusted to the point indicating the minimum current value when the car 1 has passed through the middle floor while performing the descent operation, and the maximum load of the load indicating the minimum current value is set. The ratio to the load is set to 45% to 55% for a passenger elevator. According to the inspection standards of elevators issued by the Japan Building Equipment & Lift Center, the balance point is adjusted by 0%, 100% and 110% of the rated load in the car 1 for DC motors, and AC 0%, 25%, 50%, 75%, 100% and 11 for motor
The car 1 is reciprocated once with the load 5 of 0% loaded thereon, and the motor current is measured by the ammeter 6 to create a characteristic curve 7 when rising and a characteristic curve 8 when falling as shown in FIG. The balance point 9 of the car from the intersection of these characteristic curves 7 and 8
Is calculated, and the weight of the counterweight 13 is adjusted so that the balance point 9 is 45% to 55% of the maximum load in the car 1.

In order to adjust the balance point in this way, a load of 110% of the rated load is indispensable, and these loads must be unloaded for measurement at each load. A great deal of labor and time was required. Therefore, as a method of calculating a balance point without using a load in order to reduce the labor and work time of an operator, a method disclosed in Japanese Patent Laid-Open No. 3-120180 has been proposed. The adjustment method of this balance point is to prepare in advance a characteristic curve representing the relationship between the motor load and the load load of the elevator determined by the rated speed, the rated load load, the type of motor and the balance point, and prepare the following. The elevator car is run with no load and the motor current values at the time of ascent and descent are measured, and the above-described characteristic curve is translated in parallel with these motor current values as starting points, and a balance point is calculated from the intersection of the characteristic curves. And to determine the amount of counterweights to be unloaded.

[0005]

However, the conventional method for calculating the balance point of an elevator car is that, when the motor capacity is determined by the rated speed, the rated load, and the type of the motor, the motor current with respect to the load load at the time of ascending and descending is determined. It is assumed that the characteristic curve that expresses the relationship is necessarily determined.However, it may be applicable if the characteristic curve of the motor current is a straight line like a DC motor, but it may be applicable based on actual machine measurement data. According to the motor characteristics, when the current curve is expressed as a function of quadratic or higher as in an AC motor, the degree of opening of the characteristic curve, that is, the slope of a straight line, and the slope of an nth-order curve The coefficient of n is not necessarily determined only by the motor capacity determined by the rated speed, the rated load capacity, and the type of the motor. It did not match the actually measured draw curve no matter how translating a characteristic curve as a reference. Even if the coefficient of n is a constant characteristic curve,
As a method of translating the two characteristic curves at the time of ascending and descending, as shown in the characteristic curve diagram of FIG.
8, a method of simultaneously moving the characteristic curves 7, 8 in parallel with each other in the direction of the vertical axis as shown in the characteristic curve diagram of FIG. FIG.
As shown in the characteristic curve diagram of FIG. 7, there is a method of individually translating the characteristic curves 7 and 8 in the horizontal axis direction, and the method is not uniquely determined. Therefore, the balance point 9 which is the intersection of the characteristic curves 7 and 8 is also determined. could not.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an elevator car balance point adjusting method capable of calculating an accurate balance point using a light load that reduces the labor and work time of an operator. is there.

[0007]

According to the present invention, in order to achieve the above object, a car and a counterweight are connected via a rope, and the car is driven up and down by a motor. , The balance point of the elevator car is calculated, and the balance weight of the elevator is adjusted based on the calculated balance point of the elevator car. The stationary torque to keep the stationary, and the starting torque when rotating the motor in the opposite direction, respectively, measured in a plurality of different loads in the car, from the difference between the static torque and the starting torque Calculate the approximate straight line, calculate the unbalance load from this approximate straight line, and calculate the balance point from the unbalance load. Characterized by being adapted to.

According to the method for adjusting the balance point of an elevator car according to the present invention, a light load is placed on the elevator car,
The static torque that keeps the force that the motor tries to rotate due to the load difference between the car and the counterweight and the starting torque when the motor tries to rotate in the opposite direction measured multiple times under different loads, Then, since the balance point was calculated based on the measured static torque and starting torque, the load state in the car can be set to the no-load state or the light-load state. There is no need to use a 110% load, and an accurate balance point can be calculated using a light load that reduces the labor and work time of the operator.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 4 is a schematic configuration diagram of an elevator that employs the elevator car balance point adjusting method according to one embodiment of the present invention. The traction machine 11 and the sheave 4 are respectively connected to the rotating shaft 12a of the motor 12, and the car 1 and the counterweight 13 are connected to both ends of the rope 3 wound around the sheave 4, respectively. The sheave 4 is rotated via the traction machine 11 by the rotation of the motor 12 according to the command, and the car 1 is operated to move up or down. The ammeter 6 is connected to the motor 12, and the ammeter 6 measures a torque current value of the motor 12 when the car 1 moves up and down. A handwheel 14 is attached to the motor shaft 12 a of the motor 12, and a torque wrench 24 is attached to the handwheel 14.

Next, the procedure for obtaining the balance point in the elevator will be described with reference to the flowchart shown in FIG. First, in step S1, the car 1 is moved so that the car 1 and the counterweight 13 are on the same floor, and the main power of the elevator is shut off in that state. In step S2, the handwheel 14 is connected to the motor shaft 12a of the motor 12 by the handwheel 14. And a hand wrench 14 with a torque wrench 1
4a is attached. Generally, the relationship between the load of the elevator car 1 and the counterweight 13 is such that the car 1 and the counterweight 13 are balanced when a half of the maximum load of the car 1 is applied. Therefore, the brake 15 of the motor 12 is manually released by a brake release lever (not shown) while holding down the handle 14 with a load of not more than half of the maximum load, here, the car 1 is not loaded. Next, in step S3, the weight 1 is balanced with the car 2.
After measuring the static torque 20a that can keep the stationary state of the car 3 with the torque wrench 14a, the car 1 is rotated in the direction in which the car 1 descends from the stationary state by measuring the starting torque 21a of the car 1 in step S4. .

Next, a light load 5 that is less than half the maximum load 5
Is actually measured at least once under the actual load condition in which the vehicle is mounted in the car 1. Here, 80, which is sufficiently smaller than the rated load
The measurement is carried out twice with a light load of 160 kg and a light load of 160 kg, respectively.
Static torque 20c and starting torque 21 at 0 kg load
Measure c. In this way, the measurement of the static torque and the starting torque in a light load state that is equal to or less than half of the maximum load is three times in total including the no-load state, but it is desirable to perform at least two times. Moreover, if the measurement under the no-load state is included once, the work of loading and unloading the actual load into and out of the car 1 is reduced, and the burden on the operator is reduced.

Thereafter, at step S6, each static torque 20
Approximate straight line 22 is obtained from the difference between a to 20c and each of starting torques 21a to 21c. This is obtained by plotting the measurement results of each static torque and each starting torque on a torque / load characteristic diagram showing the torque on the vertical axis and the load on the horizontal axis, respectively, as shown in FIG. Straight line 2
Since 0 can be obtained, an approximate straight line 22 of {(static torque + starting torque) / 2} is obtained based on these data. Subsequently, in step S7, the unbalance load of the car 1 and the counterweight 13 is obtained from the intersection 23 of the approximate straight line 22 with the load axis where the torque = 0. In step S8, a balance point is calculated from {unbalance load / maximum load × 100 (%)}. In the vicinity of the unbalance load = 0, assuming the gear ratio M, the gear frictional resistance G, and the frictional resistance S in the tower such as the car guide bush 16, the static torque TS and the starting torque TK are represented by the following equations [1] and [2]. ].

TS = M (W1−W2) − (G + S) [Equation 1] TK = M (W1−W2) + (G + S) [Equation 2] As described above, the approximate straight line 22 is ｛(TS) + (TK2) )
/ 2}, it is expressed as the following equation [3]. (TS + TK) / 2 = M (W1−W2) [Equation 3] As can be seen from the equation [3], the intersection with the load shaft where the gear friction resistance G and the tower friction resistance S cancel each other out and the torque = 0 is obtained. It becomes unbalanced load. When the unbalance load is obtained in this way and the balance point is obtained, 4
It becomes 5.65%.

FIG. 2 is a characteristic diagram showing the relationship between the loaded load and the motor current in the realization field. The horizontal axis is the percentage of the ratio of the loaded load in the car to the rated loaded load, and the vertical axis is the motor current value. Is represented. This characteristic diagram shows that the rated speed of the elevator is 60 m / min and the rated load is 6
In a realization place of a 00 kg elevator, a rising curve 18 and a falling curve 19, in which various loads are actually loaded in a car and the ascending and descending motor current values are respectively measured, are shown from the intersection 10 thereof. The balance point is 45.99%.

[0015] The actually measured balance point of 45.99%
And the balance point 45.6 obtained as described above.
Comparing 5%, the difference is only 0.34%, which indicates that an accurate balance point can be estimated. Moreover, since the estimation can be performed without using the actual load of 110% of the loaded load as in the related art, the labor of the operator can be significantly reduced. In addition, in a state where the car 1 of the elevator is in a no-load state and in a light load state sufficiently smaller than the rated load, the stationary torques 20a to 20c in which the car 1 is stationary and the starting torques 21a to 21c when the car 1 starts in the descending direction. Only by measuring the motor 21c with the motor shaft 12a, the balance point can be easily and accurately calculated. Based on this, the amount of the counterweight 13 to be loaded / unloaded in step S9 can be calculated, so that the working time can be reduced. In addition, since the balance point can be accurately adjusted, the unbalance amount of the weight 13 in balance with the car 1 is reduced, the slip of the rope 3 on the sheave 4 and the wear of the sheave 4 are reduced, and the landing accuracy of the car 1 is improved. As a result, no unnecessary load is placed on the motor 12, so that the motor 1
2 also improves the efficiency and has the effect of energy saving.

In the above embodiment, the static torque 2
The handwheel 14 to which the torque wrench 14a can be attached is used when measuring the torques 0a to 20c and the starting torques 21a to 21c. However, in the case of the motor 12 in which a torque wrench mounting member is previously installed on the motor shaft 12a, the handwheel is used. 14 is unnecessary. Also, if each torque value is used for controlling the elevator, if a calculation device for automatically calculating a balance point from this torque value in a control device (not shown) or a display device for displaying the same is provided. For example, the balance point can be calculated without using the torque wrench 14a. If the data of the static torques 20a to 20c and the starting torques 21a to 21c measured at the time of the elevator inspection are stored, the current unbalanced load, the balance point and the load to be adjusted are calculated and displayed using these data. A portable maintenance inspection work instruction device can also be used.

[0017]

As described above, the method for adjusting the balance point of an elevator car according to the present invention measures the static torque at which the car is stationary and the starting torque when the car starts up in the downward direction, and measures these measured values. Since the balance point is calculated based on the above, the measurement can be performed with a sufficiently small light load or no load, and the balance point can be calculated easily and accurately, and it is necessary to set the predetermined balance point. Since the adjustment of the counterweight can be performed, the work of loading and unloading a load of 110% of the rated load as in the related art is omitted, so that not only the labor of the operator is significantly reduced, but also the working time is shortened. be able to.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a method for adjusting a balance point of an elevator car according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram illustrating a relationship between a loaded load and a motor current for explaining calculation of a balance point by actual measurement.

FIG. 3 is a torque / load characteristic diagram illustrating calculation of a balance point according to the elevator car balance point adjustment method shown in FIG. 1;

FIG. 4 is a schematic configuration diagram of an elevator that implements the elevator car balance point adjusting method shown in FIG. 1;

FIG. 5 is a characteristic diagram illustrating an example of calculating a balance point according to a conventional elevator car balance point adjustment method.

FIG. 6 is a characteristic diagram illustrating another example of calculating a balance point by a conventional method of adjusting the balance point of an elevator car.

FIG. 7 is a characteristic diagram illustrating still another example of calculating a balance point by a conventional method of adjusting a balance point of an elevator car.

FIG. 8 is a characteristic diagram illustrating still another example of calculating a balance point by a conventional method of adjusting the balance point of an elevator car.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Basket 3 Rope 12 Motor 13 Counterweight 15 Brake 20a-20c Static torque 21a-21c Starting torque 22 Approximate straight line 23 Unbalance load

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenichi Fujitani 1-6-6 Kandanishikicho, Chiyoda-ku, Tokyo, Japan Inside the Hitachi Building System Co., Ltd. (72) Inventor Satoshi Yamamoto 1-6-6 Kandanishikicho, Chiyoda-ku, Tokyo, Ltd. Hitachi Building Systems Co., Ltd. (72) Inventor Makoto Shimodera 1-6-6 Kandanishikicho, Chiyoda-ku, Tokyo F-term in Hitachi Building Systems Co., Ltd. 3F304 BA07 EA00

Claims (3)

[Claims] A car and a counterweight are connected via a rope, and the car is driven up and down by a motor. A load is arranged in the car to calculate a balance point of the elevator car. In the elevator car balance point adjusting method for adjusting the counterweight based on the stationary torque for keeping the force that the motor tries to rotate due to the load difference between the car and the counterweight, and the motor in the opposite direction. The starting torque when rotating the car is measured in each of a plurality of states where the load in the car is different, an approximate straight line is obtained from the difference between the static torque and the starting torque, and an unbalanced load is calculated from the approximate straight line. And the balance point is calculated from the unbalanced load. Lance point adjustment method. 2. The elevator car balance point adjusting method according to claim 1, wherein the plurality of states in which the loads in the car are different include a no-load state. 3. The elevator car according to claim 1, wherein the plurality of states in which the loads in the car are different include a no-load state and a light-load state that is equal to or less than half of the rated load capacity. Balance point adjustment method.