JP2009298582A - Control device of elevator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and accurately obtain brake torque necessary for braking a sheave of a hoisting machine without being affected by conditions of brake components, etc. <P>SOLUTION: While releasing a mechanical brake 21, a regeneration brake 22 is generated by freely moving a car 15. The speed change of the car 15 when braking by the regeneration brake 22 is detected via a speed detector 23. The brake torque necessary for braking the sheave 13 is calculated based on the relation between the speed change and torque of the regeneration brake. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an elevator control device having a function for automatically calculating a brake torque necessary for braking a sheave of a hoisting machine.

  There are two types of elevator brake mechanisms. One is a mechanical brake that brakes by physical friction, and the other is an electric brake that brakes by electric friction generated by the rotation of a motor. Some elevator products use these in combination, and mechanical brakes are used as main brakes and electric brakes as auxiliary brakes.

  It is necessary to adjust the brake torque (braking force) necessary for braking the sheave of the hoisting machine to an appropriate value for each elevator product using such a brake mechanism. This is because if the brake torque is too small or too large, a problem occurs in the operation of the elevator.

  That is, for example, when the brake torque is smaller than the required amount, there are problems that the car cannot be stopped in an emergency, or the car slips in the power running direction when stationary. On the other hand, if the brake torque is too strong, there is a problem that the passengers in the car are shocked by sudden braking. Under such circumstances, it is necessary to determine an appropriate brake torque for each elevator and adjust it to that value.

However, in general, adjusting the brake torque is very troublesome. To be specific, load the maximum load weight on the car, run it, actually operate the mechanical brake, measure the braking distance at that time, and adjust to the target braking distance. Adjust the torque value. For this reason, there is a great burden on the worker, and the adjustment work takes time. Therefore, conventionally, an apparatus that automates such an adjustment work has been considered. For example, in Patent Document 1, a brake operation command is issued by detecting that the car has reached a predetermined position, and the brake torque is calculated from the signal of the car speed and the plate operation command at that time, and automatically adjusted. A method is disclosed.
JP-A-4-315822

  However, in the method of calculating the necessary brake torque by actually operating the mechanical brake as in Patent Document 1, there is a possibility that a measurement error may occur depending on the state of the brake component such as the state of the brake pad. There is a problem that an accurate torque value cannot be calculated.

  The present invention has been made in view of the above points, and is an elevator control that can easily and accurately obtain the brake torque required for braking the sheave of the hoisting machine without being affected by the state of the brake parts. An object is to provide an apparatus.

  An elevator control device according to the present invention is an elevator control device provided with a mechanical brake and a regenerative brake as a brake mechanism for braking a sheave of a hoisting machine. Regenerative brake generating means for causing the car to move freely and generating the regenerative brake; speed detecting means for detecting a speed change of the car during braking by the regenerative brake; and speed change detected by the speed detecting means And calculating means for calculating a brake torque necessary for braking the sheave based on the relationship between the torque of the regenerative brake and the torque of the regenerative brake.

  According to the present invention, by using the regenerative brake, it is possible to easily and accurately obtain the brake torque necessary for braking the sheave of the hoisting machine without being affected by the state of the parts that depend on the mechanical brake. it can.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of an elevator according to an embodiment of the present invention. Here, an explanation will be given by taking a general slewing type (traction type) elevator as an example.

  For example, a control device 11 called a “control panel” and a hoisting machine 12 for moving the car 15 up and down are installed in a machine room of a building. There is also a machine roomless type elevator in which the control device 11 and the hoisting machine 12 are arranged in an elevator hoistway.

  The control device 11 includes a computer on which a CPU, a ROM, a RAM, and the like are mounted, and controls the entire elevator including drive control of the hoisting machine 12. The hoisting machine 12 includes a motor driven by electric power supplied from a commercial power source.

  A sheave 13 is rotatably attached to the rotating shaft of the hoisting machine 12, and a rope 14 is wound around the sheave 13. A cage 15 is connected to one end of the rope 14, and a counterweight (suspending weight) 16 is connected to the other end. Accordingly, when the sheave 13 is rotated by driving the hoisting machine 12, the car 15 and the counterweight 16 are moved in a hoistway manner through the rope 14 wound around the sheave.

  In the figure, 17a and 17b are guide rails for supporting the car 15 in the moving direction, and 18a and 18b are guide rails for supporting the counterweight 16 in the moving direction.

  A tail cord 19 that is a signal transmission cable is attached to the bottom of the car 15, and an end of the tail cord 19 is connected to the control device 11. Various signals are exchanged between the control device 11 and the car 15 via the tail cord 19.

  Here, a mechanical brake 21 and a regenerative brake 22 are provided as an elevator brake mechanism. The mechanical brake 21 is disposed on the circumferential portion of the sheave 13 and applies a brake by contacting the sheave 13. The mechanical brake 21 includes an electromagnetic brake, but is not particularly limited to the structure in the present invention.

  The regenerative brake 22 is an electric brake, and uses the kinetic energy (regenerative energy) generated from the hoisting machine 12 as electric energy to rotate the motor rotor in the direction opposite to the traveling direction for braking. Call.

  A speed detector 23 composed of a pulse generator (PG) is installed on the rotating shaft of the sheave 13. The speed detector 23 generates a pulse signal in synchronization with the rotational speed of the sheave 13 and outputs the pulse signal to the control device 11. In the control device 11, the rotational speed of the sheave 13, that is, the speed of the car 15 is detected by counting the number of pulses per unit time.

  FIG. 2 is a block diagram showing a functional configuration of the elevator control device 11 in the same embodiment.

  The control device 11 includes a control unit 31, a storage unit 32 connected to the control unit 31, an interface (I / F) unit 33, and a display unit 34.

  The control unit 31 includes a CPU, and executes various processes related to the operation of the elevator by starting the program 32a stored in the storage unit 32, and executes arithmetic processing for calculating necessary brake torque described later.

  The storage unit 32 stores various data including a program 32a. Here, a table 32b showing a relationship between the speed and the regenerative brake torque (see FIG. 6B) is stored. The interface unit 33 receives the pulse signal output from the speed detector 23.

  In addition, the display unit 34 displays the necessary brake torque calculated by the calculation process of the control unit 31. This display part 34 consists of a liquid crystal display panel etc., for example, and is arrange | positioned in the place where an operator is easy to visually recognize.

  FIG. 3 is a diagram showing a configuration of an elevator drive system in the same embodiment.

  As an elevator drive system, a three-phase AC power supply 41, a converter 42, a smoothing capacitor 43, and an inverter 44 are provided.

  The three-phase AC power supply 41 is a commercial power supply and supplies a three-phase AC voltage. The converter 42 converts this AC voltage into a DC voltage. Smoothing capacitor 43 smoothes the voltage converted into direct current by converter 42. The inverter 44 is controlled by the control device 11, generates an AC voltage having a predetermined frequency from the DC voltage supplied from the converter 42 via the smoothing capacitor 43, and supplies this to the motor of the hoisting machine 12 as drive power.

  On the other hand, at the time of regeneration that does not require power, regenerative energy flows backward from the hoist 12 toward the inverter 44. The regenerative brake 22 is configured to brake the sheave 13 using the regenerative energy at this time. In addition, since the structure of this regenerative brake 22 is generally known, the detailed description is abbreviate | omitted here.

  In such a configuration, when there is a travel command for the elevator (car 15) from the control device 11, the required power is supplied from the inverter 44 and the hoisting machine 12 is driven. As the hoisting machine 12 is driven, the sheave 13 rotates and the car 15 moves to the destination floor via the rope 14. At this time, the mechanical brake 21 as the main brake is in a state of being separated from the sheave 13 (open state).

  Further, when the car 15 is stopped, the control device 11 activates the mechanical brake 21 and the regenerative brake 22. These brakes 21 and 22 stop the movement of the car 15 by braking the shaft of the sheave 13 of the hoisting machine 12.

  Here, the brake torque necessary for braking the sheave 13 is the diameter of the sheave 13 or the articles that operate integrally through the rope 14 (for example, the car 15, the counterweight 16, the tail cord 19, etc.), It depends on the loading weight of the car 15. If the brake torque is too strong, sudden braking is applied, and the car 15 vibrates greatly, impacting the passengers in the car 15. Therefore, the brake torque needs to be adjusted to an appropriate value within a certain range.

  The present embodiment is characterized in that the brake torque required at this time is calculated using the regenerative brake 21. That is, the relationship between the speed of the car 15 (that is, the rotational speed of the sheave 13) and the regenerative brake torque is uniquely determined by the characteristics of the motor used in the hoisting machine 12. Further, with the generation of the regenerative brake 22, the speed of the car 15 dynamically changes. The speed change at this time is given by the regenerative brake 22 acting on the drive system of the elevator. Therefore, by measuring the speed change at that time, it is possible to obtain the necessary brake torque for the current unbalance amount.

  The work procedure necessary for this method is roughly divided into five steps S1 to S5 as shown in FIG. 4, all of which are automatically performed by the control device 11.

  (1) The mechanical brake 21 is released (OFF), and the elevator car 15 is freely moved.

  The term “free movement” as used herein refers to moving the car 15 in the upward direction. That is, in order to reduce the work amount of the worker as much as possible, the car 15 is made empty without being loaded with a weight. In the lift type elevator, when the car 15 is emptied and the mechanical brake 21 is released, the car 15 moves in the upward direction due to the weight of the counterweight 16.

(2) The regenerative brake 22 is operated.
(3) A change in speed during braking is detected.
(4) Calculate the required brake torque.
(5) Display the calculation result.

  Here, the necessary brake torque calculation process (4) will be described in detail with reference to FIGS.

  Now, as shown in FIG. 5, it is assumed that an unbalance torque Na is generated due to a weight difference between the car 15 and the counterweight 16. In this state, when the mechanical brake 21 is released and the car 15 freely moves, the regenerative brake 22 is generated. In order to detect the speed change of the car 15 at this time, the control device 11 acquires the angular speed ω and the speed v of the rotation of the sheave 13 from the speed detector 23 and differentiates the angular speed ω by a predetermined time unit to obtain the angular speed. Find the acceleration ω '.

  Next, the control device 11 refers to the table 32b stored in the storage unit 32 to obtain the value of the regenerative brake torque Nr with respect to the speed v. Note that the value of the regenerative brake torque Nr may be obtained by a predetermined arithmetic expression each time without using the table 32b.

  FIG. 6 is a graph showing these relationships. FIG. 6A shows the time-series change of the angular velocity ω, and FIG. 6B shows the relationship between the speed v and the regenerative brake torque Nr. FIG. 7C shows time-series changes in the angular acceleration ω ′ and the regenerative brake torque Nr.

Here, in general, the relationship between the torque N and the angular acceleration ω ′ is expressed as follows:
Iω '= N
Can be expressed as

In this case, since the regenerative brake torque Nr is generated,
N = Na (unbalance torque) −Nr (regenerative brake torque)
It becomes.

  On the other hand, the moment of inertia I is a data set corresponding to the loaded load of the car 15. Therefore, the control device 11 obtains the values of the unbalance torque Na and the moment of inertia I based on the time series data of the angular acceleration ω ′ and the regenerative brake torque Nr shown in FIG.

When the unbalance torque Na and the inertia moment I of the elevator are thus obtained, the control device 11 obtains the necessary brake torque Nk using these values. In this case, the required brake torque Nk is
Iω '= N'
It can be obtained from the relationship. However, the torque N ′ at this time is
N ′ = Na (unbalance torque) −Nk (required brake torque)
It is. Therefore, the control device 11 calculates the necessary brake torque Nk by the following calculation.

Nk = Na-N '
= Na-Iω '(1)
In the above equation (1), the angular acceleration ω ′ can be appropriately set according to the allowable braking distance determined for each elevator. By inputting this allowable braking distance into the control device 11 as a measurement condition in advance, the brake torque Nk required for the drive system of the elevator is calculated.

  When the required brake torque Nk is calculated in this way, the control device 11 displays the calculation result on the display unit 34. Thereby, the operator can grasp the value of the brake torque Nk required for the elevator through the display unit 34, and can easily adjust the mechanical brake 21 according to the value. Specifically, the force of the electromagnetic spring constituting the mechanical brake 21 is adjusted according to the value of the brake torque Nk.

  As described above, according to the present embodiment, the brake necessary for braking the sheave 13 of the hoisting machine 12 provided in the elevator using the regenerative brake 22 generated when the car 15 is freely moved. Torque can be calculated. In this case, since the mechanical brake 21 is not used, an accurate required brake torque can be obtained without being affected by the state of brake parts such as a brake pad, and the torque is adjusted according to the value of the required brake torque. By doing so, the safety of the elevator can be ensured.

  In the above-described embodiment, a slewing type (traction type) elevator has been described as an example. However, the present invention is not limited to this, and the present invention is not limited to this. Is equally applicable.

  In the above embodiment, the mechanical brake 21 is adjusted when the value of the necessary brake torque Nk is found. However, it may be adjusted including the regenerative brake 22. As a method for adjusting the regenerative brake 22, a value of resistance for changing the regenerative electric power to heat may be changed. However, since the regenerative brake 22 is used as an auxiliary brake when an abnormality occurs, it is desirable that the mechanical brake 21 as a main brake has a necessary torque amount from the viewpoint of safety. .

  In short, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Moreover, various forms can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be omitted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

FIG. 1 is a diagram showing a configuration of an elevator according to an embodiment of the present invention. FIG. 2 is a block diagram showing a functional configuration of the elevator control device according to the embodiment. FIG. 3 is a diagram showing a configuration of an elevator drive system in the same embodiment. FIG. 4 is a flowchart showing a work procedure executed by the elevator control apparatus according to the embodiment. FIG. 5 is a diagram showing a state at the time of calculating the required brake torque of the elevator in the same embodiment. FIG. 6 is a diagram for explaining the time series change of the angular velocity ω obtained by the elevator in the same embodiment, the relationship between the speed v and the regenerative brake torque Nr, and the time series change of the angular acceleration ω ′ and the regenerative brake torque Nr. .

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Control apparatus, 12 ... Hoisting machine, 13 ... Sheave, 14 ... Rope, 15 ... Riding car, 16 ... Counter weight, 17a, 17b ... Car side guide rail, 18a, 18b ... Counter weight side guide rail, 19 ... Tail cord, 21 ... mechanical brake, 22 ... regenerative brake.

Claims (2)

In an elevator control device equipped with a mechanical brake and a regenerative brake as a brake mechanism for braking the sheave of the hoisting machine,
Regenerative brake generating means for generating the regenerative brake by freely moving the car with the mechanical brake released;
Speed detecting means for detecting a change in speed of the car during braking by the regenerative brake;
An elevator control device comprising: an arithmetic means for calculating a brake torque necessary for braking the sheave based on a relationship between a speed change detected by the speed detecting means and the torque of the regenerative brake. .   2. The elevator control apparatus according to claim 1, further comprising display means for displaying the necessary brake torque calculated by the calculating means.

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