JPH0416488A - Continuously variable shift driving device for elevator - Google Patents

Abstract

PURPOSE:To perform continuously variable acceleration and deceleration of rotation of a reduction gear input shaft by locating a transmission wheel such that it makes contact with a drive disc and a driven disc at a proper pressure and reciprocatively moving it on a line for intercoupling the center of the drive disc and the center of the driven disc during running of an electric motor. CONSTITUTION:Since, during movement of a transmission wheel 6 from a point A to a point B, a ratio of L1:L2 is changed, a driven disc 12 and an input shaft 13 of a reduction gear are gradually decelerated, and at a point of time when the transmission wheel is moved to the point B, high speed operation is entered. When an elevator approaches a destination floor and a deceleration signal is received, a flow rate regulating solenoid valve 17 is opened and a pressure in an oil chamber 11 is reduced, whereby the transmission wheel 6 is pushed through the force of a transmission wheel return spring 9 and started to move from the point B to the point A. Thus, the driven disc 12 and the reduction gear input shaft 13 are gradually decelerated as it follows a reverse progress to that during acceleration. After a lapse of a slight seating speed period in which return to the point A is effected, the transmission wheel 6 receives a stop signal and an electromagnetic brake 24 is operated to completely stop an elevator.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a drive device for an elevator using a squirrel cage induction motor as a power source.

(Prior art) Excluding special methods such as the hydraulic type and hoist type used mainly for low floors, the so-called crane type (rope type) is generally used as a lifting method for elevators, which is not affected by the height of the building or the speed of lifting. A method was adopted in which the basket was suspended from one end of several wire lobes hung on a car, a counterweight was suspended from the other end, and the basket was raised and lowered by the rotation of the sheave. The motor used as the driving power source is called an electric motor. Other electric motors shall be named according to their purpose or type. ) is the mainstream. Its advantages are that it is cheaper, smaller and lighter, has a more robust structure, and has quieter rotation noise than a direct-fL electric motor.
It has high efficiency, easy maintenance and inspection, etc., but its drawback is that speed control is difficult. The disadvantages of this are that the impact on the elevator is large when starting and stopping, which makes the ride uncomfortable, and because of the light weight of the load on the car, there is a problem in that when the car stops, there is a tendency for a step to form between the landing floor and the car floor. .

To date, various methods have been considered to compensate for these shortcomings, but the principles and advantages or disadvantages of the starting, decelerating, and stopping methods are explained below for each method in the chronological order in which the representative methods were put into practical use. state

(1) Two-speed system The drive unit of this system is an electric 6! speed system, as shown in Figure 6.
The motor-side coupling (25) fixed to the motor shaft (3) of (]) and the reducer input shaft (13) of the reducer (14)
Enter into. When the elevator enters the deceleration section and receives a deceleration signal, relay S opens and at the same time relay S turns on, switching to multi-pole, several-turn AI (low-speed winding ta).In order to smooth the deceleration, during the deceleration period Resistance R by relays s6 and s7
2. Short-circuit R1 one after another to reach the landing speed, and the stop signal activates the electromagnetic brake (24) to stop the elevator.

The advantage of this method is that the structure of the drive section is simple and the drive section can be manufactured at low cost, but the disadvantages are as follows.

Since the method of converting the number of poles, which is inversely proportional to the number of poles of the motor, is used, the motor (1) has two layers of windings with different numbers of poles. To explain the operation, first, when the electromagnetic switch (hereinafter referred to as a relay) S or S2 for lifting/lowering selection shown in FIG. 6 closes, the relay S closes, and the electric 11! (1) is a small number of turns! ! (high speed winding). Relay S4 closes as the starting current decreases, shorting resistor R1 and allowing high-speed operation (
rated speed operation) is large, and the ratio of the landing speed between the high speed winding and the low speed winding is not large (the low speed winding is used for low speed operation during maintenance and inspection of elevators) (For this reason, the normal winding ratio is about 4:1.) Since the landing speed is relatively fast, adjusting the electromagnetic brake (24) to be strong will shorten the time from the stop signal to the stop. The impact becomes large, and although the impact can be softened by making a weak adjustment, the level difference between the landing surface and the floor surface becomes large due to the light weight of the load.

(b) As shown in the graph of Figure 12, the starting torque (rotational force) of an induction motor is not large, so in order to increase the starting torque, the external size is larger compared to a general-purpose motor with the same output.
Also, a flat motor with two layers of windings is expensive.

(C) A large relay opens and closes continuously during startup and deceleration, which creates a lot of noise.

(d) Because a large current flows during starting and deceleration, the drive unit of this type is basically the same as the two-speed type, as shown in Figure 8, but the speed generator IN (27) is The operation and speed control method during operation of this zero-order system, which is characterized by being directly connected to the shaft of the electric motor (1), will be described.

As shown in FIG. 8, at the same time as the lift selection relay S or the relay 82 closes, the relay s3 closes and the electric a!
(1) is started, and as the starting current decreases, relay s4 closes to short-circuit resistor R1 and enters high-speed operation. Upon receiving the deceleration signal, relay S opens and at the same time relay s8 closes. At this time, the electric motor (1) is disconnected from the AC power supply and starts idling due to inertia. At the same time, the DC braking current (for sluggish braking, called DB below the dynamic brake) is rectified in the DB control circuit device (28) through relay S8. This DB current, which flows through the windings to prevent idling, is controlled in proportion to the voltage generated by the speed generator (27).That is, when the motor (1) rotates quickly, the B current increases. DB flows and increases braking force, as the rotation decreases
Adjustment is made so that the current decreases and the rotation becomes 0 at the landing position, and the stop signal activates the electromagnetic brake (24) to stop the elevator. The advantage of this method is that the speed change is very smooth from deceleration to stop, as shown in the graph in Figure 9.
Ideal deceleration and stopping without impact can be achieved. Furthermore, there is almost no difference in level between the landing floor and the spherical surface due to the light weight of the carrying load, but the following drawbacks can be cited.

(a) Since the starting method is similar to the two-speed method, the shock at starting is large.

(b) The DB control circuit device including the speed generator (27) is expensive.

(c) Due to the reason (b) in (11) above, the electric motor is large and expensive.

(d) Power consumption is large due to the reason in (d) of [1].

(e) Adjustment is complicated.

(1) VVVF method VVVF is an abbreviation for variable voltage variable frequency, and is commonly referred to as an inverter one-way system (hereinafter, an inverter one-side three-phase approximate sine wave is obtained. Three-phase AC voltage and frequency supplied to the motor (1). This is a primary mode of operation in which the output frequency and voltage can be freely controlled by increasing or decreasing the number of intermittent cycles per unit time of the power transistors T1 to T, and by changing the ratio of energized time to non-energized time. To explain the operation, as shown in Fig. 10, when the lift selection relay S or relay S closes, the motor (1) starts at low voltage and low frequency.(See Fig. 11 below) This is a method that has become mainstream in recent years with the aim of improving the level difference in the floor surface when landing and reducing power consumption.This method uses the characteristic that the rotation speed of the induction motor is directly proportional to the frequency of the power supply. Next, we will explain its principle. First, we will explain the workings inside the inverter. As shown in Figure 13, AC power is converted to DC in a part of the converter, and the inverter By sequentially cutting off the DC current supplied to a portion at high speed using the power transistors T1 to T6, the frequency and voltage decrease steplessly when the deceleration section shown in Fig. 14 is entered and a deceleration signal is received. Some time after reaching the landing speed, when a stop signal is received, the electromagnetic brake (20) is activated to stop the vehicle. Because the starting voltage and frequency are low, a large starting torque can be obtained despite the small starting current.Also, the speed during maintenance and inspection can be freely set using an inverter device, so there is no need for two-layer windings, so the motor (1) The advantage of this method is that, as shown in the graph in Figure 11, smooth acceleration and deceleration can be obtained from start to stop, resulting in a much more comfortable ride than the two methods mentioned above. There are advantages such as low power consumption because no large current flows, low landing speed so there is less shock and unevenness on the floor when landing, and low cost because the electric motor can be made smaller.However, there are disadvantages. The following points can be raised.

(a> The inverter device used in the elevator must be of the specified type depending on the measurement location.

(c) Due to the influence of high frequencies, the electric motor generates abnormal noise during operation.

(Embodiment) The structure of the present invention will be explained based on the embodiment shown in FIGS. 1 and 2. As shown in Figures 1 and 2, (1) is an electric motor, (2) is a drive plate that has a momentum effect (b), and as shown in Figure 14, the output voltage waveform is very high frequency (usually 10K).
oz to IMH2), so in order to eliminate the influence on other audio equipment, etc., it is necessary to pay attention to wiring to the motor, grounding of piping, etc., and to provide a prevention circuit in some cases.

(c) Since complex equipment is used, adjustments are complicated, and the number of engineers who can respond when a failure occurs is limited. .

(d) Each measurement used during adjustment, inspection, and inspection is moved, but installed so that it rotates synchronously with the motor shaft (3) in the rotational direction. The pressure spring receiver (4) is fixed to the motor shaft (3), and the transmission wheel (6) provided between the pressure spring (5), the passive plate (12), and the drive plate (2) is connected to the passive plate (12). Drive plate (2
) is installed by setting the spring pressure on each side of the spring to provide good transmission efficiency. The passive plate (12) is the driving plate (2
) and are fixed to the reducer input shaft (13) so as to face parallel to each other, and at a distance of 10 L2 from the center of the motor shaft (3) to the center of the reducer input shaft (13). Transmission wheel (
6) is made of a friction material such as rubber or urethane, and is fixed to the transmission axle (7) via a bearing or the like that can withstand high-speed rotation. Hydraulic pump (18), flow rate adjustment solenoid valve (]7)
When the pressure in the oil chamber (11) increases due to the action of When the pressure in the oil chamber (11) decreases, the transmission returns from point B to point A by the action of the transmission wheel return spring (9). The cylinder (8) is firmly attached to the base (22) so as to withstand the impact when the electric motor is stopped. In this embodiment, the electromagnetic brake (24) is built into the electric motor (1).The operation of the present invention will be explained based on FIGS. 2 to 5.

As shown in the circuit diagram in Figure 4, when a start command is received, relay SI or relay S2 for elevating/lowering is activated and the motor (
1) is started by releasing the electromagnetic brake (24), and at the same time relay SP and relay Sv are closed to start the hydraulic pump motor (19) and open the flow rate adjustment solenoid valve (17) (at this time, relay SV2 is always closed while AC power is supplied, energizing the solenoid valve (20), and closing the solenoid valve (20).) At the time of starting the electric motor (1), the transmission wheel (
6) is at point A shown in Figure 2, so the passive plate (1
2) and the rotation speed of the reducer input shaft (13) is electric 1! (1
) The engine starts slowly at a rotation speed of XLI/L2.

The pressure in the oil chamber (11) gradually increases due to the operation of the hydraulic pump (18), and the transmission wheel (6) starts moving from point A to point B. (The transmission wheel (6) consists of a driving plate (2) and a passive plate (12).
) is pressed with an appropriate force, so Noah remains quiet.
I have trouble moving g, 17a, but. If it is 0ゎA□, it is easy to move. ) If the flow rate is adjusted in advance with the flow rate adjustment solenoid valve (17) according to the acceleration period shown in Fig. 5, the transmission wheel (6) will reach point B at the end of acceleration and the flow rate adjustment solenoid valve (17) will be activated. closed, and the hydraulic pump electric motor (]9) stops. When the transmission wheel (6) moves from point A to point B, LI:
As the ratio of L2 changes, the passive plate (12) and the reducer input shaft (13) are gradually accelerated, and when they reach point B, they enter high-speed operation. 8 When they approach the landing floor and receive a deceleration signal, The flow rate adjustment solenoid valve (17) opens and the pressure in the oil chamber (l) decreases, so the transmission wheel (6) is pushed by the transmission wheel return spring (9) and starts moving from point B to point A. . Therefore, the passive plate (12) and the reducer input shaft (13) gradually decelerate following the reverse course of acceleration, and the transmission wheel (6) returns to point A after a short landing speed period. When the stop signal is received, the electromagnetic brake (24) is activated to completely stop the elevator. If an abnormality such as a power outage or breakdown occurs while the elevator is going up and down, if the transmission wheel (6) stops at a position close to point B, it will not be possible to play again.
! Ir (23) (Clutch brakes are announced by various companies such as electromagnetic type and hydraulic type, and are commercially available.) When starting, the brake applied to the reducer input shaft (13) is released and the passive plate shaft (13) is released at the same time. 13'> and start.When stopped, the passive plate shaft (13') is disconnected and at the same time the brake is applied to the reducer input shaft (13) to stop the elevator.In this case, the elevator is built in the electric motor (1). Electromagnetic play
1r (24) is a clutch brake. When relay Sv2 shown in the figure is opened in 1r (23), the excitation of the solenoid valve (20) is canceled and the solenoid valve (20) opens, causing a large amount of oil in the oil chamber (11). Since the oil passes through the solenoid valve (20) and returns to the oil tank (21), the pressure in the oil chamber (11) decreases in a short time. Therefore, the transmission wheel (6) quickly returns to point A before the electric motor (1) completely stops, so there is no problem when restarting.The elevator electric motor decelerates when starting and generates a large amount of power when stopping. Therefore, as in the embodiment shown in FIG.
3), and in the meantime, if the clutch is used, the users on each floor who wish to go up will get on and off at their desired floor, and then the call for the direction down will be answered. Even while the car is stopped, if the next direction of elevation is the same, the electric motor (1) and passive plate (12) continue to idle due to inertia, so power is saved when restarting. Only when the car reaches the top or bottom floor and the direction of elevation changes, or when the calls for each floor are no longer available, direct current is applied to the windings of the motor (1) to apply electrical braking and the motor (1) is activated in a short time.
to stop. Also, if you do this, even if the car suddenly stops in the event of an abnormality during a power outage, it will still be powered by 1! (]) Transmission wheel (6
) Since the passive plate (12) continues to idle, the movement of the transmission wheel (6) to return to the starting position is not forced. 13)
The sheave (16) is fixed to the speed reducer output shaft (15) that actually raises and lowers the elevator car.
The rotation speed of is expressed by the following formula.

Concerning the method of When a transmission is used in an elevator, transmission of large capacity power, transmission efficiency, gear ratio, simplification of gear change mi, f! 0 N: Number of revolutions of sheave (16), Mn: Number of revolutions of electric motor (1), L: Motor shaft Transmission wheel (6) from the center of (3)
L2: Distance from the center of the transmission wheel (6) to the center of the reducer input shaft (13), P: Number of rotations of the second reducer input shaft (13), P2 = Reducer output shaft ( 15) Number of revolutions: 0 In the embodiment of the present invention, a hydraulic method was adopted for the method of moving the transmission wheel (6) for ease of explanation, but other electric methods are also possible.

(Effects of the Invention) This invention provides the market with an induction motor that is easy to adjust, find failures, and repair without speed control when used in an elevator. I will compare and explain.

(a) Unlike when the reducer and motor are directly connected, such as in the two-speed speed system or feedback control system, the starting torque is Ll/L2 when directly connected, as shown in Figure 2, so the outside of the motor is small. , and like the above two methods, there is also a 2 for maintenance operation.
There is no need for layer winding, and a normal general-purpose motor can be used.
The electric motor is much cheaper than the three conventional methods.

(b) The transmission section of the present invention has a transmission wheel (6
), but since hydraulic pressure is not required for movement, a small hydraulic system using a low-output electric motor is sufficient, so it is not very expensive. The control unit is as simple as a hydraulic pump motor and a solenoid valve open/close relay in addition to lift and fall relays, so the control panel can be made smaller.6 Compared to the present invention, the conventional feedback control system and inverter are required. The one-sided type has multiple electric circuits, and the inverter one-sided type in particular uses various maintenance circuits, circuits to prevent influence on external equipment, and large-capacity thyristors, which can cause overheating. Since it uses a prevention fan, etc., it is very expensive.6 As mentioned above, when comparing the transmission parts, the present invention can be produced at a lower cost overall.

(c) Since the present invention starts with a low load and gradually increases the load, the starting current decreases in a very short time and the motor reaches its rated rotation. Therefore, power consumption during startup is low,
In addition, since the load is applied efficiently, the output during operation can be reduced to some extent. Among the conventional systems, the one-inverter type consumes the least amount of power, but even compared to that, it is advantageous because there is no wasted power consumed within the frequency converter.

(d) A large gear ratio can be obtained by increasing the diameters of the driving plate (2) and passive plate (12) shown in Fig. 2 and by increasing the moving distance of the transmission wheel (6) from point A to point B. .

Therefore, smooth acceleration, deceleration, and stopping are possible, so that a ride quality comparable to that of a single-inverter type and accurate landing accuracy can be obtained.

(e) Conventional feedback control systems and one-way inverter systems have extremely complex electrical circuits, making installation and adjustment complicated, and in the event of a failure, an engineer with advanced electrical knowledge is required. Since the electrical circuit of the present invention is very simple, it is easy to install and adjust, and even when a failure occurs, a wider range of engineers can respond.

(f) Maintenance operation speed during hoistway inspection can be adjusted freely as in the case of the inverter system by fixing the moving position of the transmission wheel (6) shown in Figure 2 at an appropriate position between points A and B. speed can be set.

(g) Unlike the conventional three systems in which the electric motor and reducer are directly connected, the transmission wheel (6) between the electric motor 11 (1) and the reducer (14) plays the role of cushioning the impact, so the electric motor The vibrations are not transmitted directly to the elevator, so there is less noise during operation.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a simple circuit diagram of the present invention, FIG. 5 is a graph showing the operating state of the present invention, and FIG. 6 is a two-stage speed diagram of the prior art. A simple mechanism and circuit diagram of the system, Figure 7 is a graph showing the operating state of the two-speed system, Figure 8 is a simple mechanism and circuit diagram of the conventional feedback control system, and Figure 9 is feedback control. The first RI is a simple mechanism and circuit diagram of the conventional one-way inverter type. Figure 11 is a graph showing the operating status of the one-way inverter type. Figure 12 is a diagram of the induction motor. Characteristics graph, Fig. 13 is a principle diagram of frequency conversion with one inverter type, Fig. 14 is an output waveform diagram of one inverter type, (1) is the electric motor, (2) is the drive plate, (3) is the motor shaft, ( 4) is a pressure spring holder, (5) is a pressure spring, (6) is a transmission wheel, (7
) is the transmission axle, (8) is the cylinder, (9) is the transmission car return spring, (10) is the piston, (12) is the passive plate, (1
3) is the reducer input shaft, (13') is the passive plate shaft, (14)
is the reducer, (15) is the reducer output shaft, (16) is the sheave,
(17) is a flow rate adjustment solenoid valve, (18) is a hydraulic pump, (
19) is a hydraulic pump electric motor, (20) is a solenoid valve, (21)
) is the oil tank, Cocoon 23) is the clutch brake, (24)
is an electromagnetic brake. 1 Electric motor 2/Drive plate 3 Electric whetstone 8 Cylinder 18: m pressure pump 19 Oil FE pump motor 20 Electromagnetic helmet 21 Oil tank 2.1:? C! Figure 3 Time-1-ゝ- Figure 9 Time-Ichishima- AC power supply Figure 6 1 Electric #l & Il Figure 7 Time open □2- AC power supply No. 10 [J] Motor 3: C-shaft 13 deceleration Input shaft 14, reducer 1st electromagnetic brake electric l111 force/y-pull reducer 4 coupling pulse oscillator 11 Figure time--j-

Claims (1)

[Claims] The drive plate (2) attached to the electric motor shaft (3) and the passive plate (12) attached to the reducer input shaft (13) are attached parallel to each other, and the center of the drive plate (2) and Passive board (
Set the center of 12) at an appropriate distance and fix it, then attach the drive plate (
A transmission wheel (6) made of friction material such as rubber is provided between the driving plate (2) and the passive plate (12) so as to be in contact with the driving plate (2) and the passive plate (12) with appropriate pressure. By reciprocating the line connecting the center of the plate (2) and the center of the passive plate (12) while the electric motor (1) is rotating, the reducer input shaft (13)
A continuously variable speed drive device for elevators that can freely change the speed of acceleration and deceleration of the rotation of the elevator.