JPS6119548B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an elevator hoisting device installed in a machine room of a building, and particularly to an improvement in a hoisting device equipped with an electric motor controlled by a thyristor control system.

First, a conventional hoisting device will be explained with reference to FIG.

In the figure, 1 is the architectural support, 1a is the floor of the machine room,
1b is a support protruding from this, 1C is support 1
b is a beam made of shaped steel installed between them, 3 is a vibration isolator made of vibration isolating rubber placed on top of this beam,
Reference numeral 4 denotes a hoisting machine having a hoisting machine stand 4a at its lower part, and is supported by the vibration isolator 3. Reference numeral 5 denotes a main rope that is wound around the hoist 4 and suspends a car and a counterweight (both not shown).

That is, the vibrations generated in the hoisting machine 4 are absorbed by the vibration isolator 3, thereby reducing the vibrations transmitted to the building. However, for example, in the case of the hoisting machine 4 equipped with an electric motor controlled by a thyristor control method, there was a problem in that the mechanical impedance of the beam 1c was small and the vibration damping effect was insufficient in response to the main vibration frequency generated therein. . For this reason, in the living room of the building,
Unpleasant noise was sometimes generated when the elevator was operating. On the other hand, it is necessary to increase the size of the hoisting machine base 4a in order to increase the weight of the hoisting machine 4 in order to obtain a sufficient vibration damping effect, or to install the floor 1 itself in a building in a vibration-proof manner. However, this system had the disadvantage of requiring a large-scale equipment configuration, increasing costs, and requiring complicated work such as designing each building individually.

The present invention aims to eliminate the above-mentioned drawbacks and provides an elevator hoisting device that can prevent the propagation of high-frequency vibrations generated in a hoisting machine having a thyristor-controlled electric motor.

An embodiment of the present invention will be described below with reference to FIGS. 2 to 6.

In the figure, the same reference numerals as in FIG. It is a block and consists of two pieces made of iron material or reinforced concrete blocks, and in the opposing parts of these two pieces, an insertion space 7a for the main rope 5 is formed, and a bolt 7b and a nut 7c screwed into it are formed. integrated by. Reference numeral 3 denotes a second vibration isolator made of vibration isolator rubber mounted on the vibration damping mass 7, and the hoist 4 is supported on this.

That is, the dynamic model shown in FIG. 4 is formed by the configuration of FIGS. 2 and 3, where M ₃ = mass of hoisting machine 4 M ₂ = mass of vibration damping mass 7 M ₁₁ AM ₁₂ = Mass of beam 1c I ₃ = Moment of inertia of hoisting machine 4 I ₂ = Moment of inertia of damping block 7 I ₁ = Moment of inertia of beam 1c K ₃ = Spring constant of second vibration isolator 3 K ₂ = First Spring constant K ₁ of vibration isolator 6 = Equivalent spring constant C ₃ of beam 1c = Damping coefficient C 2 of second vibration isolator 3 = Damping coefficient C ₂ of first vibration isolator ₆ A = Equivalent damping coefficient of beam 2 However, in order to simplify the explanation, if the dynamic model shown in FIG. 5 is substituted for consideration, the following equation (1) is obtained. Note that the force P transmitted to the floor is expressed by the following formula with respect to the force F generated by the hoisting machine. In this case, in order to avoid the complexity of the mathematical formulas, the case where each damping coefficient is zero is shown.

P=K ₁ K ₂ K ₃ F/A ...(1) However, A={(K ₃ −M ₃ ω ² )(K ₃ +K ₂ −M ₂ ω ² )(K ₂ +K ₁ −M ₁ ω ² )} −K ₃ ² (K ₂ +K ₁ −M ₁ ω ² ) −K ₂ ² (K ₃ −M ₃ ω ² ) where ω=circular frequency.

From equation (1), a frequency response characteristic regarding the transmitted force shown by curve A in FIG. 6 can be obtained. On the other hand, the response characteristic of the device configuration shown in Fig. 1 is curve B.
The transmission force corresponding to the natural oscillator of the beam 1c, that is, the frequency f ₂ in FIG. 6, is much smaller in curve A than in curve B. Also, in addition to this
Above 50 Hz, especially in the 100-300 Hz band,
As shown by hatching in FIG. 6, the transmitted force can be reduced. In this case, the hoisting machine 4
The weight of the vibration damping block 7 is 0.1 to 1.0 times, for example, 1/2 of the weight excluding the hoisting machine stand 4a.
By setting it to a certain degree, the transmission force can be reduced by 10 decibels or more. In addition, by making the size of the vibration damping block 7 almost the same as the hoisting machine stand 4a, that is, generally about 45 to 60 cm in width, 150 cm in depth, and 25 cm in height, it is possible to reduce the transmission force. The required weight and moment of inertia are obtained. Therefore, the vibration damping mass 7 can be manufactured lightweight and inexpensively, and since it is less restricted by the installation conditions of the building, it can be manufactured with high productivity and the installation work can be simplified. A device configured simply as described above can prevent the propagation of high frequency vibrations.

Note that the vibration of the hoisting machine 4 having a thyristor-controlled electric motor is 2 to 6 times the power supply frequency, that is,
100 Hz to 300 Hz, and the natural frequency mainly dominated by the first vibration isolator 6 and damping mass 7 is 2 to 300 Hz.
If the natural frequency in the vertical direction in FIG. 2 is set to 70 hertz, that is, equivalent to 2 to 70 hertz, the effect of reducing the transmission force at the vibration frequency of the hoist 4 can be increased.

To further explain this, as _shown in _FIG .
If the frequency is within the range of 70 hertz, the vibration transmission force will be reduced in the above-mentioned range of 100 to 300 hertz. This is attributable to the fact that the natural frequencies dominated by the first vibration isolator 6 and the damping mass 7 are moving away from the range of 100 to 300 hertz.

On the other hand, as shown in curve B in Figure 6, if the natural frequency governing the vibration isolator approaches the range of 100 to 300 hertz, the vibration transmission force within the range of 100 to 300 hertz is sufficient. Not discounted. Therefore, the sixth
As shown by a and b in the figure, it has a larger transmission force than curve A, and generates vibrations and noise, but according to the present invention, curve A
As shown in , the vibration transmission force can be reduced.

In this way, the smaller the natural frequency that governs the vibration isolator and damping mass, the smaller the transmission rate at the vibration frequency of 100 to 300 Hz generated by the motor, but the lower the transmission rate at the vibration frequency of 100 to 300 Hz, which is generated by the electric motor. From the viewpoint of manufacturing costs, etc., it is practical to keep the value within this range.

In addition, in this embodiment, the vibration damping mass 7 can be divided by removing the bolts 7b and nuts 7c, so when renovating an existing elevator to improve its vibration damping properties, it is possible to The cable 5 can be easily placed in the space 7a.

As explained above, the present invention provides a second vibration isolator on the first vibration isolator under the vibration damping mass so that the weight of the vibration damping mass is 0.1 to 1.0 times the hoisting weight. A vibration system with a natural frequency of 2 to 70 Hz is constructed by the mass and the first vibration isolator, and a hoist is placed on the second vibration isolator to support the vibration damping mass etc. It is supported by the body. This makes it possible to significantly reduce the transmitted force in the 100 to 300 Hz band due to the vibration of the hoist, and in particular, the vibration of the hoist with a thyristor-controlled electric motor can be reduced from 2 to 6 of the power frequency. Since the vibration frequency is twice as high, an effective transmission force reduction effect can be obtained at this vibration frequency, thereby realizing an elevator hoisting device that can provide a quiet living environment.

In addition, the damping mass is made up of multiple members and has a divisible structure, and the spaces for the main cable insertion are made to face each other so that they can be divided into parts at the main cable insertion part, so that it can be easily used in existing elevators. It is extremely easy to carry out repairs.

[Brief explanation of the drawing]

FIG. 1 is a side view conceptually showing a conventional elevator hoisting device, FIG. 2 is a view corresponding to FIG. 1 showing an embodiment of the elevator hoisting device according to the present invention, and FIG. 4 is a mechanical model of FIG. 1, FIG. 5 is a mechanical model summarizing FIG. 4, and FIG. 6 is a transmission force-frequency characteristic diagram of FIG. 5. 1 is a building support, 1b is a support, 1c is a beam, 3
is the second vibration isolator, 4 is the hoisting machine, 6 is the first vibration isolator, 7
is a damping mass. In addition, the same parts or corresponding parts in the figures are indicated by the same reference numerals.

Claims (1)

[Claims] 1. In an elevator hoisting machine having a thyristor-controlled electric motor and supporting the hoisting machine by a building support, the first
A vibration isolator and a vibration system supported by the first vibration isolator and having a weight of 0.1 to 1.0 times the hoisted weight and having a natural frequency of 2 to 70 hertz, and A member having a cavity through which the main rope of the elevator is inserted is arranged so that the cavities face each other, and a plurality of vibration damping masses are connected together, and the member is placed in the vibration damping mass to drive the hoisting machine. An elevator hoisting device comprising: a supported second vibration isolator.