JPH0729746B2 - Elevator emergency stop control device - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an emergency stop device for an elevator, and more particularly to an emergency stop control device suitable for reducing the inertia of the elevator device.

[Background of the Invention]

Generally, as shown in FIG. 1, the mechanical system of an elevator apparatus has a drive motor 1, a speed reducer 2 and a sheave 3, which are connected to each other, and a counterweight 5 via a rope 4 wound around the sheave 3. The car 6 is suspended. A friction brake device 7 is provided for braking and holding the car 6 stationary, which generally comprises a brake coil 7C, a brake shoe 7S, a brake drum 7D, or this 7S.
It is known to configure 7D with a day brake.

In such a structure, when the elevator 6 is driven by the electric motor 1 and the elevator car is running, if the elevator has some trouble, the driving force of the electric motor 1 is shut off and the brake device 7 is operated to operate the elevator car. 6 is in an emergency stop. That is, the friction brake device 7 is also used as a protection device for safely stopping the car 6 even when the elevator control device or the like is abnormal.

Therefore, even when the elevator adopts the method of obtaining the braking torque or the method of reducing the landing shock by controlling the braking force of the friction brake device 7 at the time of normal deceleration stop, in the case of the abnormal condition, It is devised to give priority to safety by operating the friction brake device 7 unconditionally.

By the way, it is known that the capacity and power consumption of the electric motor 1 can be reduced by reducing the inertia ratio of the mechanical system shown in FIG.

Therefore, recently, it has been considered to further reduce the inertial performance rate to save power.

However, it was found that the following problems newly arise when the inertia is lowered. That is, as described above, when the elevator is in an abnormal state, the friction brake device 7 should be operated to secure safety first, but if the inertia ratio is small, the car 6 will suddenly stop. If the deceleration at this time becomes large, the shock given to the passengers becomes large, which is dangerous. Therefore, the friction brake device 7
However, in this case, the deceleration distance will be long, so if an abnormality occurs during a descending operation with full capacity or an ascending operation with few passengers, it will not be possible to stop at the end floor. , Causing a push-down or push-up,
There is a possibility of serious accident. Further, the friction braking device 7 requires at least a braking force to hold the car 6 stationary in a state in which passengers having a capacity equal to or larger than the passengers are on board, and from this point as well, there is a limit to weakening the braking force.

Therefore, there is a limit to reducing the above inertial performance rate.

[Object of the Invention]

An object of the present invention is to provide an elevator emergency stop control device capable of reducing the inertia ratio and eventually saving power while maintaining safety when an elevator is abnormal.

[Outline of Invention]

Here, first, the relationship between the braking force of the friction brake device (hereinafter simply referred to as the braking force) and the inertial performance rate is clarified.

FIG. 2 shows the relationship between the load in the car during the ascending operation and the car deceleration α during the brake operation.

First, the deceleration α when the brake is applied is Required by.

Where K is a coefficient determined from the reduction ratio of the reduction gear and the sheave diameter (m) T _B ; Brake torque (Nm) T _L x; Load torque (Nm) T _L x = K (W _L x-W _C ) (N ・ m) W _L x; Car load (Kg ・ f) W _C ; Counterweight (Kg ・ f) J; Elevator performance (Kg ・ m ² )

Further, as described above, the upper limit value α _{UL of} acceleration that does not harm passengers and the lower limit value α _DL of acceleration that does not cause thrust up / down at the end floor are given when the brake is applied. Therefore, even if the load in the car and the driving direction are different, the deceleration α of the car needs to be α _UL α α _DL, and at the time of ascending operation, L ₁ in the figure obtained by equation (1) It is necessary to set it so that it has the characteristics shown.

Slope k ₁ of the characteristic L ₁ has a relationship of k ₁ k ₀ when the slope k ₀ properties L ₀ connecting the lower alpha _DL and upper alpha _UL deceleration, further unloaded NL characteristic L ₁ Deceleration of α _N1
Must be α _N1 α _DL .

Where k ₁ and α _N1 are T _LF ; Unbalance torque at full load (N ・ m) T _L0 ; Unbalance torque at no load (N ・ m) W _LF ; Unbalance load at full load (Kg)

Therefore, it is necessary to set the inertial performance ratio J from the equation (2) and the brake torque T _B from the equation (3).

The inertia factor J obtained from the above relationship is usually very large, and an inertia factor 3 to 6 times the inertia factor of a linear system obtained from the weight of the car and the counterweight is applied to the rotary system on the electric motor shaft, such as a brake drum. Needs to be provided by making it larger than its function.

Therefore, the torque for driving the elevator increases, and the energy consumed by the electric motor naturally increases.

Next, the basic idea of the present invention will be described. Third
Similar to FIG. 2, the figure shows the relationship between the load amount and the deceleration during the ascending operation.

First, the moment of inertia as possible function on minimal when the J _2, for the characteristic L ₀ of the aforementioned The case where there is a relationship of

If the characteristic L ₀ , the required brake torque T _B0 is constant,
In the case of the inertia ratio J ₂ , the deceleration of NL under no load α _N2 = k _J α
The characteristic is L _{2 in} the figure with _DL and slope k ₂ = k _J · k ₀ . For this characteristic, it is necessary to weaken the brake torque so as to exceed the upper limit value α _UL in almost all regions.

The brake torque T _{B3 at} this time is However, it becomes α _N3 α _DL .

The characteristic when the brake torque is T _B3 is L _{3 in the} figure. Here, since the slope of the characteristic L ₂ is the same as when the brake torque is weakened, the shaded portion in the figure exceeds the upper limit α _UL .

Therefore, if the braking torque is further weakened and the deceleration of HL at balanced load is set to α _H4 , α _H4 exceeds the lower limit α _DL ,
Set the FL deceleration at full load so that α _F4 is below the upper limit α _UL . When the brake torque at this time is T _B4 , α _H4 α _DL Becomes

In this case as well, the shaded portion in the figure naturally falls below the lower limit value α _DL .

Therefore, during ascending operation, the brake torque is switched to T _B3 (characteristic L ₃ ) in the region from no load NL to the equilibrium load HL, and the brake torque is switched to T _B4 in the region above the equilibrium load HL. The characteristic L _UP shown by the solid line can be obtained. In addition, since the load torque at the time of descending operation is opposite to that at the above-mentioned ascending operation at the equilibrium load HL, the characteristic
As shown in Fig. ₄ , L ₃ and L ₄ are L ₃ ′,
L ₄ ′.

Therefore, the characteristic L _DN shown by the dotted line in the figure can be obtained by switching the brake torque to T _B4 in the unloaded NL to the balanced load HL and to the brake torque in the balanced load HL or more to the T _B3 .

From the above, if k _J 2, the deceleration α can be made α _DL α α _UL by switching the brake torque in two stages or more.

Next, the case of having a relationship of J ₀ / J ₂ = k _J > 2 will be described.

Also in this case, as in the case of k _J 2, the slope k ₀ of the characteristic L ₀ becomes k _J times, and when k _J is 2 <k _J 3, there are 3 or more steps and 3 <k _J.
In No. 4, if the braking torque is set in four stages or more and the braking torque is switched according to the load amount, the deceleration within the upper limit α _UL and the lower limit α _DL can be achieved.

As an example of this, FIG. 5 shows the relationship when k _J = 3.

The brake torques may be set to T _B01 , T _B02 , and T _B03 so as to have the characteristics L ₀₁ , L ₀₂ , and L ₀₃ shown in the figure, and the torques may be switched according to the load state.

In addition, the brake has the purpose of not only stopping the elevator while it is traveling but also holding the elevator car stationary. The torque for maintaining the stationary state is usually required to be equal to or more than the torque for maintaining the state in which 180 to 200% of the rated load amount of the elevator is loaded.

When the stationary holding torque is T _BS , if the maximum value of the brake torque of the above setting is lower than T _BS , for example,
When the maximum value T _{B3 of the} setting is T _BS <T _B2 , the torque T _BS for holding the brake torque still is generated.

Summarizing the above, when the slope at low inertia is k _J times the slope k ₀ obtained from the upper limit α _UL and the lower limit α _{DL of the} deceleration, the brake torque is equal to or greater than the value obtained by adding 1 to the integer part of the slope k _J. Make settings. Further, when the elevator holding torque is lower than the stationary holding torque among the set values of the torque, the braking torque to which the holding torque is further added is set.

The principle of the present invention has been described above, but in order to facilitate understanding, a case has been described as an example in which the load torque T _L x is obtained from the relationship with the counterweight with reference to the in-car load amount. However, the load torque T _L x is not limited to the above method, and the load torque applied to the rotating shaft of the motor during traveling can be detected directly, or by detecting the magnitude of the motor current, for example. The braking force may be controlled according to the load torque thus detected.

That is, the present invention controls the braking force according to the load viewed from the rotating shaft of the electric motor, that is, the load of the elevator, and is not limited to the detection method.

Example of Invention

An embodiment of the present invention for performing the torque switching shown in FIG. 4 will be described below.

FIG. 6 shows the magnitude of the brake torque required for the configuration of FIG. 4 (two-stage switching). Figure torque T _2, T _1, T ₀ has a relationship of _{T 2> T 1> T 0} = 0, T 2 is T _B3, T ₁ in FIG. 4 described corresponds to T _B4, braking torque T ₀ (= 0) is when the elevator is running.

FIG. 7 shows the relationship between the torques T ₁ and T ₂ at the time of abnormality. As is known from Fig. 4, the torque T ₁ rises above the equilibrium load HL or rises below the equilibrium load HL, and the torque T ₂ rises below the equilibrium load HL or falls below the equilibrium load HL. Must be applied during operation.

FIG. 8 shows a brake control circuit for controlling the torque. Normally, the brake has a braking spring, and the maximum braking force is set by this braking spring force. At this time, the magnitude of the torque is determined by the current passed through the electromagnetic coil 7C of the brake. That is, when the current flowing through the coil 7C increases, a torque that cancels the braking spring force is generated.

The brake control circuit 8 is composed of an alternating current power supply AC, rectifiers 81, 82 to 84 for converting electric alternating current into direct current are resistors for suppressing a current flowing through the coil 7C, and R10 ₁ and R20 ₁ are composed of an a contact of a relay described later. .

In the above circuit, when the contact R20 ₁ is open, since the circuit is interrupted, the torque by the braking spring force, i.e., where
A torque of T ₂ is generated. Further, when the contact R20 ₁ is closed and the resistor 82 is short-circuited by the contact R10 _{1, the} brake torque is set to T ₀ = 0 and a torque T ₂ is generated when the resistor 82 is inserted. Further, for the opening and closing of the contacts, an abnormality detecting device E, a driving direction detecting device DE, a load detector 60 mounted under the floor of a car or the like, and a load detecting device WD for determining a load amount based on the detector, a speed detecting device This is performed by the determination circuit 9 to which the signal of the zero speed detector VD that detects the zero speed from the signal from 10 is input.

The determination circuit 9 will be described below with the relay sequence shown in FIG.

In Fig. 9, R10 is O from start to stop during normal operation.
N relay, R10T is a time relay that is turned off after a time t _{D from} R10, R20 is a relay that adjusts the brake torque, and RE is off when the abnormality detector E detects an abnormality.
Relay, RE ₁ is a normally open contact of the relay RE, R10 ₂ , R10 ₃ and R10 ₁ shown in FIG. 8 are normally open contacts of the relay R10, R10T ₁
Is the normally open contact of the time relay R10T, and Fig. R20 ₁
Indicates a normally open contact of the relay R20. RP ₁ is a relay normally open contact that turns off when the car is at a stop level, RHF ₁ is a relay normally open contact that turns on when the output of the load detection device WD is above the balanced load, and RNH ₁ is on when the load is below the balanced load HL Normally open contact of the relay, RUP ₁ is the normally open contact of the relay that turns ON during upward operation in the direction DE detection, RDN ₁ is the normally open contact of the relay that turns ON during downward operation, and RV ₁ is the speed at the zero speed detector VD. Indicates a normally open contact of a relay that turns off when is less than or equal to zero.

The time chart of the above embodiment is shown in FIG. 10 by using a solid line when normal and a dotted line when abnormal.

First, normal operation will be described. In FIG. 9, it is assumed that the abnormality detection relay RE is turned on because of normal operation, its contact RE ₁ is closed, and the stop level detection relay contact RP ₁ by the position signal is also closed. Therefore, at startup, the relays R10, R10T, and R20 are
It is turned on by the operation of and is held by the contact R10 ₂ .

Therefore, in the brake control circuit 8 of FIG.
Since 0 ₁ and R20 ₁ are closed, the brake is opened, the electric motor 1 is activated, and the car 6 starts traveling. When the stop level level is reached, the stop level detection relay contact RP ₁ is opened, and since the speed is almost zero, the zero speed detector VD outputs the zero speed detection relay contact RV ₁ . Was but connexion, relay R1 by contact RP ₁
0, also the relay R20 is off by contact RV _1. Therefore, in the brake circuit of FIG. 8, the current is cut off by R20 ₁ , and the maximum set torque T ₂ is applied to the brake.

That is, as shown in FIG. 10 (A '), the brake torque is T ₀ (= 0) at the time t ₀ (at the start) under normal conditions, and T ₂ (the maximum set value) at the time t ₃ (at the time of stop). Becomes

Next, the emergency stop when an abnormality occurs will be described. In FIG. 10, consider a case where an abnormality occurs at time t ₁ while the elevator is traveling. When an abnormality occurs, the abnormality detector E operates in the sequence shown in FIG.
turn off. The contact RE ₁ turns off R10 and the time relay R10T turns off after a delay of time t _D. In this case the braking torque adjustment relay R20 are between drawing colors are off by contact R10 ₃ if open circuit condition. From this the normal time similar Figure 8 brake circuit 8 is cut off by the contact of the contact R20 _1, the brake torque T ₂ of the maximum setting is applied as shown in Figure No. 10 (B '). The open circuit condition between the aerodynamics is under ascending load below the equilibrium load HL or under descending operation under the equilibrium load HL. In this case the but connexion, deceleration indicated by the dotted line portion of the solid line portion of the characteristic L ₃ of Figure 4 and the characteristics L ₃ ', i.e., α _UL> α> α to emergency stop at deceleration alpha within the range of _DL Can be done.

Then, if inter-Gray in Figure 9 is closed conditions, adjusting the relay R20, the contact also contacts R10 ₃ is opened R10T ₁ - Contact
RV _1- It is in the ON state because the air is closed. At this time, as described above, the relay R10 is off. Therefore, in the brake circuit 8, the contact R20 ₁ is closed and the contact R10 ₁ is open, so that the resistor 82 is inserted. That is, the brake torque is applied with a magnitude of T ₁ . After that, only time t _D elapses and the time relay R10T
or off, when the speed has decreased and the zero by application of the brake, by opening the contact RV ₁ contact R10T ₁ or speed detection of the relay, as the relay R20 in the 10th view of (c) of
f It was but connexion, because it is blocked by the brake circuit also its contacts R20 _1, brake torque is maximum setting T ₂ is applied. Therefore, the brake torque state in this case is as shown in FIG. 10 (c ').

The closed circuit condition between the above-mentioned Iro is a balanced load HL or more (contact RHF ₁ closed circuit)
In rising operation (contact RUP ₁ closed), or balanced load HL below a descending operating at (contacts RNH ₁ closed) (Contact RDN ₁ closed), the solid line portion and characteristics L ₄ Characteristics L ₄ shown in FIG. 4 The vehicle will stop at the deceleration indicated by the dotted line in ′.

With the above configuration, it is possible to reduce the stop shock at the time of emergency stop even when the inertia is reduced. Conversely speaking, it is possible to further reduce the inertia.

By the way, for safety of the elevator, in order to prevent thrust up / down, a forced deceleration switch is applied to apply a brake when the stop level on the top floor and the bottom floor is exceeded, and when the elevator is running. A final limit switch FLS is installed to operate. Safety can be prioritized by connecting the contact FLS ₁ to the power supply line as shown in FIG. 9 so that the set maximum torque is applied when the final limit switch FLS operates.

When the load detection 60 malfunctions, for example, when the load is determined to be equal to or more than the balanced load despite no load and the ascending operation is performed, the magnitude of the brake torque becomes smaller than the required torque.

In order to prevent this, an interlock circuit or the like may be used for high reliability, or the load detection unit may be configured as shown in FIG. 11 in order to achieve two layers of fail-safe.

FIG. 11 is an embodiment for constructing a fail-safe load detection device by detecting a frequency according to the load and using it as a load signal.

In the figure, 61 is the floor surface of the car 6, 62 is the outer frame of the car, 63 is an elastic member such as rubber or spring that is inserted between the floor surface 61 and the outer frame 62 and contracts according to the load amount, 64 Is a mounting plate that is mounted on the floor surface 61 and that interlocks with the load, the mounting plate
Holes of H ₁ and H ₂ at different positions are drilled at 64. 65 is attached to the outer frame 62 and has two light emitting diodes P
1, P2 mounting plate, P is light emitting diode P1 and P2
A frequency generator for applying a pulse voltage of frequencies ₁ and _{2 to} the receiver, PR is a receiver for detecting the signals of the light emitting diodes P1 and P2 through the holes H ₁ and H ₂ of the mounting plate 64, and D is the receiver PR. It is a frequency determiner that determines the frequency of the detected frequency signal.

Here, the size of the hole H ₁ is such that the signal from the light emitting diode P 1 is passed at the position where the load is no load to the balanced load, and the hole H ₂ is at the position where the load is equal to or more than the balanced load.
Process so that the signal of will pass. The light-emitting diode P1 generates a frequency ₁ signal emitted from the frequency generator P, and similarly, the light-emitting diode P2 generates a frequency ₂ signal ( ₁ ≠ ₂ ).

In the above configuration, the frequency determiner D has a frequency bandwidth Δ, and when a signal of ₁ −Δ < ₁ < ₁ + Δ is detected, a signal indicating no load to a balanced load or less, and ₂ −Δ < _When a signal of ₂ < ₂ + Δ is detected, a signal indicating that the load is equal to or more than the balanced load is output to the determination circuit 9 in FIG. Therefore, the judging circuit 9 controls the brake torque based on these signals in the same manner as described above. However, when the signal from the frequency judging device D disappears due to a frequency outside the above range or a damage of the light emitting diode, The load signal contacts RHN ₁ and RHF ₁ shown in FIG. 9 are configured to be opened. Therefore, when there is no signal, including when there is a power failure, the above contacts RHN ₁ and RHF
_{Since 1} can be operated on the open side, the brake torque control of the present embodiment can be made completely safe.

Although the case where the braking force is controlled in two steps has been described above, the braking force is controlled based on the above-described operation principle of the present invention by detecting the load amount according to the number of steps even when the number of steps is increased. it can.

Next, another embodiment of the brake control circuit 8 is shown in FIG.
In this figure, points different from FIG. 8 will be described.
The control circuit 8 controls the DC power source DC according to the frequency signal input _S.
The frequency signal _S is a frequency command for obtaining the brake torque shown in FIG. 4 from the magnetic multivibrator 85, and is determined by the determination circuit 9. Is output by the magnetic multi-control circuit 11 in response to the signal.

As a result, no current flows through the brake coil 7C when the magnetic multivibrator 85 fails, or when the output of the magnetic multicontrol circuit 11 is released or when the output is zero, and the brake torque becomes the maximum torque. That is, it is possible to achieve a fail safe.

Although the specific examples have been described above, the present invention is not limited thereto. For example, the load detector 60 continuously detects the load amount using a differential transformer or the like, and is indicated by a dotted line in FIG. A frequency signal that configures the signal circuit using a microcomputer and continuously controls the magnetic multivibrator.
By generating _S , the shock at the time of abnormal stop can be made constant. In this micro computerization, by adopting the frequency signal explained in FIG. 11 for the load detecting section, more complete fail-safe operation can be achieved. Further, in the above embodiment, the brake torque after the elevator is stopped is set to the maximum, but the brake torque may be controlled according to the load so that it can be held stationary even during the stop. Further, as the friction brake device, a brake drum type device is shown, but a disc brake can be similarly configured.

〔The invention's effect〕

According to the present invention, the friction braking force at the time of emergency stop is set so as to weaken the brake torque in accordance with the increase of the load that opposes the driving direction on the electric motor rotating shaft, so that the deceleration of the elevator is kept within a certain safe range. It is possible to prevent an accident due to a shock given to passengers due to excessive deceleration and an accident to push up or push down to the end floor due to excessive deceleration, and to safely stop the car during an emergency stop.

Even if the inertial performance rate is reduced, it is possible to prevent the elevator from being pushed up or down, which allows a significant reduction in power consumption.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of an elevator mechanical system, FIG. 2 is an explanatory diagram of an elevator friction brake torque setting method, and FIG.
FIG. 4, FIG. 5 and FIG. 5 are explanatory views showing the method for setting the friction brake torque according to the present invention, FIGS. 6 and 7 are explanatory views of the friction brake torque characteristic according to the present invention, and FIG. 8 is an elevator according to the present invention. An example of an emergency stop control device, Fig. 9
8 is a diagram showing an embodiment of the decision circuit of FIG. 8, FIG. 10 is a time chart for explaining the operation of FIGS. 8 and 9, and FIG. 11 is a diagram of an embodiment of a load detector according to the present invention. The drawing is another embodiment of the elevator emergency stop control device of the present invention. 1 ... Electric motor, 2 ... Reducer, 6 ... Car, 7 ... Friction brake, 8 ... Brake control circuit, 85 ... Magnetic multivibrator, 86 ... Transformer, 9 ... Brake force judgment circuit, 10: Speed detection device, 11: Magnetic multivibrator control signal generation circuit, AC: AC power supply, DC: DC power supply, E: Abnormality detector, DE: Driving direction detector, WD
...... Load amount judgment device, VD ・ ・ ・ Zero speed detection device, P ・ ・ ・ Frequency signal generator, P1, P2 ・ ・ ・ Light emitting diode, PR ・ ・ ・ Optical receiver, D ・ ・ ・ Frequency signal judgment device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaru Komuro 3-1-1, Saiwaicho, Hitachi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Toshiro Narita 3-chome, Saiwaicho, Hitachi, Ibaraki No. 1 in Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor, Ishi Tashiro, 3-1-1, Saiwaicho, Hitachi City, Ibaraki Prefecture In Hitachi Research Laboratory, Hitachi, Ltd. (72) Noboru Arahori, Katsuta, Ibaraki 1070 Ichige, Hitachi, Ltd., Mito Factory (56) References Japanese Patent Laid-Open No. 52-51644 (JP, A)

Claims (7)

[Claims] 1. An elevator car comprising an elevator car, an electric motor for driving the car, and a friction brake device for braking the traveling of the car. When the elevator is abnormal, the friction brake device is operated to operate the car. In an elevator device for making an emergency stop of a car, a means for detecting a load that opposes the driving direction on the motor shaft, and a braking force weaker than that when the detected load is small when the detected load is large during the emergency stop. An emergency stop control device for an elevator, comprising: means for controlling the brake device to generate the brake. 2. The friction braking device according to claim 1, wherein the braking force control device is provided for a predetermined time after the elevator is abnormal, or on condition that the car has decreased to a predetermined speed or less. Elevator emergency stop control device configured to generate the maximum braking force of the elevator. 3. The friction braking device according to claim 2, wherein the friction braking device is an electromagnetic braking device that releases the braking force according to a power supply voltage, and the braking force control means is the electromagnetic braking device under the above conditions. An emergency stop control device for an elevator that is configured to cut off power supply to the elevator. 4. The emergency stop control device for an elevator according to claim 1, wherein when the load detection means or the braking force control means fails, the maximum braking force of the friction brake device is generated. . 5. The load detection means according to claim 4, wherein the load detection means produces an output when the detection means is normal, and the braking force control means has a maximum value when the load detection means produces no output. Elevator emergency stop control device configured to operate with braking force. 6. The braking force control means according to claim 4, wherein the braking force control means produces an output when the control means is normal, and the friction brake device has a maximum when the braking force control means produces no output. Elevator emergency stop control device configured to operate with the braking force of. 7. The braking force control means according to claim 6, wherein the braking force control means includes a DC power source, a multivibrator for converting the DC power source into AC power according to a frequency command corresponding to an elevator load, and the AC power. An emergency stop control device for an elevator, which comprises a transformer for inputting to the primary winding, and the friction brake device is configured to release the braking force according to the power supply voltage using the output of the secondary winding of the transformer as a power source. .