JPH0780645B2 - Hydraulic elevator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hydraulic elevator, and more particularly to a control device for a hydraulic elevator that drives a hydraulic pump and controls the discharge amount of the hydraulic pump to raise and lower a car. is there.

[Conventional technology]

As a conventional hydraulic control system for a hydraulic elevator, there is a motor rotation control system. This normally works as a check valve for the cylinder that raises and lowers the car, and drives the constant discharge pump that sends pressure oil through an induction switching valve that is electrically connected in the reverse direction by the biasing of the electromagnetic coil. At this time, the voltage and frequency are changed and the rotation speed of the electric motor is changed over a wide range to variably control the oil discharge amount of the pump to raise and lower the car.

There is an oil leak in the hydraulic pump.Therefore, there is a range where the car is not started even if the hydraulic pump is rotated.If the hydraulic pump is driven by a start command, a start shock will occur and the ride comfort will be poor. Atsuta

As a solution to this problem, oil discharge corresponding to the amount of oil leakage is performed in advance, that is, a bias pattern signal for operating the electric motor at a low speed that does not start the car and a pattern signal for running the car are superimposed. There is proposed a technique for allowing the car to start smoothly.

Japanese Patent Publication No. Sho 64-311 discloses a technique for superimposing both signals of a bias pattern and a running pattern.

[Problems to be Solved by the Invention]

In the prior art, in order to obtain a bias pattern for reducing the starting shock, the load of the car, the oil temperature of the oil tank, and the oil leakage amount for each hydraulic pump are calculated based on no load and an oil temperature of 0 ° C. I was looking for the amount of oil leakage in actual operation.

The amount of oil leaked from the hydraulic pump varies depending on the manufacturing process of the hydraulic pump, and the amount of oil leaks gradually changes with age.

That is, it is difficult to always accurately grasp the amount of oil leakage in order to reduce the startup shock, and since the bias pattern is indirectly obtained by calculation, there is a limit in reducing the startup shock.

An object of the present invention is to provide a hydraulic elevator in which the starting shock can be made extremely small even if oil leaks.

Another object of the present invention is to provide a hydraulic elevator that can smoothly shift from starting compensation to traveling to the next destination floor and improve its speed control performance.

[Means for Solving the Problems]

A feature of the present invention is that, in a hydraulic elevator that adds a start compensation command to a torque command at startup, the speed of the electric motor rotated based on the start compensation command is superimposed on the speed command before the speed command rises. It is to have a means to do.

[Action]

It is possible to directly generate an appropriate bias pattern corresponding to the amount of oil leakage, and according to the present invention configured as described above, an indirect calculation is performed using an oil leakage coefficient that changes over time, as in the above-described conventional technique. The bias pattern is not obtained by explicitly obtaining the oil leak amount, and is not affected by the oil leak amount variation or the oil temperature variation for each hydraulic pump. That is, when the start compensation is completed, the electric motor rotating by the start compensation command should have a rotation speed that compensates for the leakage amount of the hydraulic pump. In addition, it shows the accurate leak amount of the hydraulic pump, and the starting shock due to the oil leak of the hydraulic pump can be reduced, and the comfortable starting can be obtained.

Further, the transition from starting compensation to traveling to the next destination floor is smoothly performed, and the amount of oil leakage during traveling is compensated to improve speed control performance.

〔Example〕

Hereinafter, the present invention will be described based on an embodiment shown in FIGS. 1 to 7.

In FIG. 1, 1 is a hoistway, 2 is a cylinder embedded in a pit of the hoistway 1, 3 is pressure oil filled in this cylinder, 4 is a plunger supported by this pressure oil, and 5 is this plunger. A car fixed to the top of 4 and 6 are induction type position detectors provided on the car 5 and detect the door zone and the stop position when facing the shield plates 7 and 8 mounted on each floor. . Reference numeral 11 denotes a pulse encoder for detecting the car speed and position, which is directly connected to a pulley 9 installed in the lower part of the hoistway 1. Pulley 9 is the top pulley 10
And, via the rope 11a fixed to the car 5, it rotates in synchronization with the movement of the car.

Reference numeral 12 is an electromagnetic switching valve that always functions as a check valve and is switched by energizing the electromagnetic coil to conduct electricity in the reverse direction. 12a is connected between the cylinder 2 and the electromagnetic switching valve 12, A hydraulic pump for transmitting and receiving pressure oil to and from the electromagnetic switching valve 12 via the pipe 13a, and 14 for the superposition of the car 5 itself and the weight of passengers in the car 5, etc. A pressure detector that detects the pressure of the cylinder 2 as the load of the car, 17 is an oil tank that sends and receives pressure oil to the hydraulic pump 13 via the pipe 17a, and 21 is a hydraulic pump via pulleys 18 and 19 and a belt 20. Three-phase induction motor that drives 13, 22 is a pulse encoder for detecting the rotation speed of this three-phase induction motor 21, R, S, T are three-phase power supplies, 25 is AC to DC, or DC to AC Converter to convert, 24 is smoothing capacitor, 23
Is an inverter that generates a three-phase alternating current with a variable voltage and a variable frequency by controlling the pulse width of the direct current. 26 is a signal 11a of the pulse encoder 11 for detecting the position and speed of the car 5, a signal 6a of the induction type position detector 6 for detecting the stop position of each floor, and the rotational speed of the three-phase induction motor 21. Speed feedback signal 22a of the pulse encoder 22 and the pressure detector 1
4 a signal 14a of a speed control device signals are input via the normally open contact 43 _a1 of Operation Command 43 until stop command exits the normally closed contact 43 b ₁ from the startup command, and outputs a signal 23a It controls the inverter 23 and outputs a signal 12b to control the electromagnetic switching valve 12.

The control device of the converter 25 is not shown because it is not particularly related to start compensation.

A schematic structure of the speed control device 26 is shown in FIG.

Incidentally, in FIG. 2, those shown in FIG. 1 but not closely related to the speed control are omitted for simplification, and the same ones as shown in FIG. The same reference numerals are attached.

In FIG. 2, 30 is a current control circuit that outputs the control signal 23a of the inverter 23 using the output i * of the vector control circuit 31 as an input, and the vector control circuit 31 is a pulse encoder 22.
, That is, the rotation speed ω _rM of the induction motor 21 and the output of the speed control circuit (ASR) 32, that is, the torque command τ * commensurate with the load of the car. The ASR circuit 32 includes a speed command ω _r1 output from the speed command generation circuit 33 and a speed memory circuit 36.
Output of the start compensation circuit speed command ω _r2 (ω _r3 ) is added by the adder 35, the rotation speed command ω _r * and the output of the pulse encoder 22, that is, the rotation speed ω _rM of the induction motor 21, and , The start compensation command τ which is the output of the start compensation command generating circuit (start compensation command giving means) 34 according to the present invention
(Reference start compensation command τ ₀ ) is input. According to the present invention, the output signal 14a of the pressure detector 14, that is, the cylinder oil pressure is input to the start compensation command generating circuit 34. 41a
Reference numerals ₂ , 41b ₁ , 43a ₁ , 43b ₁ , and TON2a ₂ are contacts of a relay described later, and their operation will be described in detail later.

The detailed structure of the speed control device 26 is shown in FIG.

The relay contacts 41a ₁ and 41a ₃ will be described in detail later.

The start compensation command τ is input to the ASR circuit 32. This is because there is a torque limiter in the ASR circuit, and in principle, it is the input to the vector control circuit 31. .

The speed control of the car 5 by the speed control device 26 will be described later. Below, the outline of the up and down movement of the car 5 and the start compensation will be described.

First, the ascending operation will be briefly described with reference to FIG.

By the operation command relay (43) described later (Fig. 7), time t
_{At 0} , the start compensation command τ rises gently. ASR circuit 32, vector control circuit 31, and current control circuit 30 with start compensation command τ
The inverter 23 is controlled by the output signal 23a via, and the induction motor 21 is rotated at a low rotation speed. The rotation speed is increased until the output pressure of the hydraulic pump 13 becomes higher than the pressure of the cylinder, the check valve of the electromagnetic switching valve 12 is opened, and the start compensation command τ is increased until the car slowly rises, and the preset time is set. Hold at t ₁ . At this time, the rear left (Figure 6) the rotational speed omega _rM ON Day rate timer (TON 2) of the normally closed contact Ton2A ₂ opens the induction motor 21 at a speed storage circuit 36 of the start compensation velocity command omega
_It is stored as _r2 (ω _r3 ).

Next, the speed command omega _r1 at time t ₂ rises, accelerates until time t _3. Further, infra at time t ₂ (FIG. 7) of the boot compensation command output control relay (41) is turned on, the speed command omega _r1 to start compensating the rotational speed command omega _r2 normally open contact 41a ₂ is closed adder 35 is added and the rotation speed command ω _r * for the induction motor 21 is A
It becomes the input of the SR circuit 32. Further, at time t ₂ , the normally-closed contact 4 between the start compensation command generation circuit 34 and the ASR circuit 32, which will be described later in FIG.
1b ₁ opens and the start compensation command τ becomes zero, and at the same time the ASR circuit 32
The normally open contact 41a _{3 of} is closed and the speed feedback control function operates. Times of Day
Follows the rotation speed command ω _r * until t ₄ and runs at the rated speed. When the elevator approaches the destination floor, the car position signal
Deceleration is started using 11a, the speed is reduced to near the stop position, and the landing speed is reached at time t ₅ . Then Operation Command at time t ₆ (43) is turned off by the stop position signal 6a, it stops the elevator. Next, at time t ₇ , the start compensation output control relay (41) is turned off, and the operation ends.

Here, the start-up compensation will be described in detail with reference to FIG.

As an input signal of the start compensation command generating circuit 34 shown in FIG. 6 (a), the normally open contact 43 of the operation command relay (see FIG. 7) is used.
a ₁ , normally closed contact 43b ₁ and cylinder oil pressure, ie pressure detector
The 14 signal 14a is input and the reference activation compensation command τ ₀ is output. FIG. 6 (b) is an output circuit of the reference start compensation command τ ₀ ,
FIG. 6 (c) is a sequence circuit used in the output circuit of the reference start compensation command τ ₀ shown in FIG. 6 (b), and FIG. 6 (d) is the output pattern of the reference start compensation command τ ₀ (bias pattern). ), FIG. 6 (e) shows the relationship between the power supply voltage (reference voltage) E ₁ of the output circuit of the reference start compensation command τ ₀ of FIG. 6 (b) and the cylinder pressure, that is, the signal 14a of the pressure detector 14. It is a thing.

In FIG. 6 (b), OP is an amplifier, R _{1 to} R ₂ are resistors, C is a capacitor, and other symbols are described in the following text.

The 6 When diagram normally open contact 43a ₁ of the Operation Command of (c) is closed, the normally closed contact of the relay 64 is turned on Day rate timer TON 2 TO
Turn on via N2b. After that, the time delays, the normally closed contact TON2b of the on-delay timer TON2 opens, and the relay 64 turns off. On Day rate timer delay time TON2 is T ₁ shown in FIG. 6 (d). In FIG. 6 (b), the output circuit of the reference start compensation command τ ₀ is an integrating circuit because the normally closed contact 43b ₁ of the operation command relay is opened. When the normally open contact 64a of the relay 64 is closed, the reference starting compensation command τ ₀ rises with the power supply voltage E ₁ as the reference voltage and having an inclination as shown in FIG. 6 (d). Next, at time T ₁ , the normally open contact 64a of the relay 64 is opened, so that the output of FIG. 6 (b), that is, the reference start compensation command τ ₀ is held at a constant value. After that, the elevator travels to the destination floor as described in FIG. 4, and when the operation command relay turns off, the normally open contact 43b ₁
Is closed and the electric charge of the capacitor C is discharged through the resistor R ₃ to return to the initial state.

Here, the relationship between the power supply voltage of the output circuit of the reference starting compensation command τ ₀ of FIG. 6 (b), that is, the reference voltage E ₁ and the cylinder pressure, that is, the signal 14a of the pressure detector 14, is based on FIG. 6 (e). Will be described in detail.

The value at point A in FIG. 6 (e) is the value at which the car slowly increases from time T ₁ under no load, and the value at point B is the value at which the car slowly increases from time T _{1 at} full load. Figure 6 (a)
In the start compensation command generation circuit of, the values of the points A and B, that is, the pressure detector output 14a at no load and at full load is supplied to the voltage E ₁
By changing the conversion level, the value converted to
It is adjustable after the elevator is installed, and has the function of continuously changing the reference voltage E ₁ from no load to full load, that is, from point A to point B. FIG. 6 (d) shows respective patterns when the reference voltage E ₁ is at points A and B shown in FIG. 6 (e).

Next, regarding the ascending operation shown in FIG. 4, FIG.
It will be described with reference to the drawings.

FIG. 7 shows a sequence circuit, and the reference symbols in the figure will be described first.

In FIG. 7, (+) and (-) are positive and negative terminals of the DC power supply, a relay 60 is a relay for confirming safety, and 45b is a normally closed contact of a safety device (not shown). 43 is an operation command relay, 60a ₁ is a normally open contact of the safety confirmation relay 60, and 10a is a normally open contact of an operation generation command relay 10 (not shown).
TON1 is an on-delay timer, which turns on with a delay after the normally-open contact TON2 _a1 of the on-delay timer TON2 is closed. There are normally open contacts DN _a1 of the relay DN input directs the lowering operation (not shown) and normally open contact UPa relay UP for commanding increasing operation (not shown) of the speed command generating circuit 33. Normally open contact UPa closes increasing operation speed command that is generated, lowering the operating speed command and the normally open contact DN _a1 is closed occurs. 41 is a start compensation command control output relay. TOFF is an off-delay timer, which turns off with a delay when the normally open contact of the input opens. Reference numeral 63 is a relay for controlling the electromagnetic switching valve 12, which opens the electromagnetic switching valve 12 when turned on, and closes the electromagnetic switching valve 12 when turned off.

Now, when the normally open contact 10a of the driver generation command relay 10 is closed, since the normally open contacts 60a ₁ of the safety check relay is closed Operation Command 43 is turned on. When the operation command relay 43 is turned on, as shown in FIG. 6 (d), the reference starting compensation command τ ₀ rises with a slope in a pattern under an arbitrary load. At the same time, the normally open contact 43a ₃ closes and TOFF turns on.

Since it is the ascending operation, the descending operation command relay DN is off and the relay 63 that controls the electromagnetic switching valve is not on. Sixth
The time T ₁ in FIG. 4D coincides with the time t _{1 in} FIG. Start compensation command τ (reference start compensation command τ ₀ ) at time t ₁
Is constant.

On Day rate timer TON2 of FIG. 6 (c) is turned on at time t _1. Normally open contact TON2a ₁ closed, on-delay timer
TON1 is turned on at time t ₂ is delayed. Normally open contact at time t ₂ TON1
a _1, TON1a ₂ is closed. Also, at time t ₂ , the normally open contact TON1a ₂
The start compensation command output control relay 41 is turned on via TOFFa ₁ . Passenger cage 5, the rotational speed command omega _r speed command omega _r1 and starting compensation rotational speed command omega _r2 of FIG. 3 is added by the adder 35
It accelerates by the command of *, and then it becomes steady speed operation. Time t ₄
Deceleration starts at and landing speed is reached at time t ₅ . Then the time
the normally open contact 10a of the operation generation command of FIG. 7 is opened at t _6, the operation command relay 43 is turned off. When the operation command relay 43 is turned off, the normally open contact 43a _{2 in} FIG. 7 opens, the speed command ω _r1 becomes zero, and the induction motor 21 rotates at a slight speed by the start compensation rotation speed command ω _r2 . 6th when the operation command relay 43 is turned off
Normally closed contact 43 b ₁ is closed in FIG. (B), returns to the initial state to discharge the capacitor C. Also, the normally open contact 43a ₃ opens,
Off-delay timer TOFF is turned off after a delay. At time t ₇ , the normally open contact TOFFa ₁ opens and the start compensation command output control relay 41
Turns off and the operation ends.

The above is the case of the ascending operation, but the case of the descending operation will be described with reference to FIG.

At time t ₀ , the start compensation command τ is gently raised and the induction motor 21 is rotated at a low speed. Increase the rotation speed until the output pressure of the hydraulic pump 13 becomes higher than the hydraulic pressure of the cylinder 3,
Increase the start compensation command τ until
Hold constant at t ₁ . At this time, as shown in FIG. 3, the rotation speed ω _rM of the induction motor 21 is stored in the speed storage circuit 36 as the start compensation rotation speed command ω _r2 (ω _r3 ).

Then, the electromagnetic switching valve 12 at time t _2, the electromagnetic coil is energized by the signal 12b conducts in the reverse direction.

At time t ₂ , the normally open contact 41a ₂ of the start compensation command output control relay shown in FIG. 3 is closed, and the start compensation rotation speed command ω _r2 is added to the speed command ω _r1 by the adder 35 to rotate the induction motor 21. The speed command ω _r * becomes the input signal of the ASR circuit 32,
Accelerate to t ₃ . Start deceleration at time t _4, becomes implantation rate at time t _5, Operation Command 43 at time t ₆ is turned off, the time t ₇
Then, the coil of the electromagnetic switching valve 12 is demagnetized, and the function of the check valve is restored.

The descending operation will be described in detail below with reference to FIGS. 5 to 7.

At time to, the operation command relay 43 turns on. Figure 6 normally open contact 43a ₁ is closed (c), the relay 64 is turned on. The normally closed contact 43b ₁ of FIG. 6 (b) is opened, the normally opened contact 64a is closed, and as shown in FIG. 6 (d), the reference start compensation command τ ₀ rises with an inclination in an arbitrary load pattern. . It turned off and on Day rate timer TON2 at the time T _1, the relay 64 to open the normally closed contact TON2b is turned off. The time T ₁ coincides with the time t _{1 in} FIG. 5,
At time t ₁ , the start compensation command τ (reference start compensation command τ ₀ ) becomes constant. When the normally open contact 43a ₃ is closed, the off-delay timer TOFF is turned on.

At time t ₂ closes the normally open contact Ton1A ₁ ON Day rate timer TON1, through the normally open contact DNa ₁ descending Operation Command DN,
Causes the speed command generation circuit 33 to generate a descending operation speed command.
Also, the normally open contact TON1a ₂ of the on-delay timer closes,
The start compensation command output control relay 41 turns on. The electromagnetic switching valve control relay 63 is turned on by closing the normally-open contact 60a ₂ of the safety confirmation relay, the normally-open contact DNa ₂ , and the normally-open contact TON1a _{3 of} the descending operation command relay, and the electromagnetic switching valve 12 is reversed by the signal 12b. Conduct in the direction.

The passenger cage 5 will accelerate until the time t _3, the steady running. When approaching the destination floor, the vehicle decelerates at time t ₄ and reaches the landing speed at time t ₅ . Opens the normally open contact 10a of the operation generating the relay 10 at time t _6, the operation command relay 43 is turned off. Off-delay timer at time t ₇
TOFF turns off, normally open contact TOFF1a ₂ opens, electromagnetic switching valve control relay 63 turns off, and electromagnetic switching valve 12 returns to the check valve function by signal 12b, and at the same time, normally open contact TOFFa ₁ opens and compensation is performed. The command output control relay 41 turns off, and the operation ends.

Here, rotate the induction motor 21 at a low rotation speed to
The rotation speed is increased until the output pressure of 13 becomes higher than the hydraulic pressure of the cylinder 3, the start compensation command τ is increased until the car rises at a slight speed, and is held at time t ₁ , and then the rotation speed command ω at time t _2.
Explain the establishment of *.

By supplementing the leak of the hydraulic pump 13, the reduction of the starting shock accompanying the oil leak is achieved.

In the hydraulic system, the friction between the cylinder and the plunger is large, and the difference between static friction and dynamic friction is large. Therefore, in the present invention, the hydraulic pressure of the cylinder 3 is detected, and A, shown in FIG.
By setting (adjusting) the positions of both points B, that is, the value of the reference voltage E ₁ slightly higher than the reference voltage value corresponding to the cylinder oil pressure itself at no load and full load, the hydraulic pump
The rotation speed of the induction motor is increased until the output pressure of 13 becomes higher than the cylinder oil pressure, and the transition from static friction to dynamic friction is smoothly performed when the plunger 4 moves, thereby further reducing the starting shock. There is.

If the difference between static friction and dynamic friction is not so great, or if it can be ignored and is not felt by the human body as a startup shock,
The reference voltage E ₁ shown in FIG. 6 (e) can be set to a value lower than the values at points A and B.

FIG. 3 shows the speed controller 26 of FIG. 2 in more detail.

This configuration is an example of a basic circuit of slip frequency vector control.

Reference numeral 30 is a current control circuit, 31 is a vector control circuit, and 32 is an ASR circuit.

The input signal of the ASR circuit 32 is the rotation speed command ω _r * obtained by adding the speed command ω _r1 of the speed command generation circuit 33 and the start compensation rotation speed command ω _r2 of the speed memory circuit 36 with the adder 35 and the rotation speed of the induction motor. The signal ω _rM and the start compensation command τ of the start compensation command generation circuit 34. The ASR circuit 32 is composed of a proportional-plus-integral constant Ki, Z ⁻¹ of a Z function for sample value control, a proportional constant Kp, a torque limiter, and an adder-subtractor.

When the operation command relay 43 turns on, the start compensation command generation circuit
A start compensation command τ (reference start compensation command τ ₀ ) is generated from 34 and becomes the command value τ * of the vector control circuit 31 via the normally closed contact 41b ₁ and the torque limiter. At this time, the normally open contact 41a ₁
Is open, the integration function does not work and the start compensation command τ
Becomes the command value τ * of the vector control circuit 31 as it is.

The start compensation command τ of the vector control circuit 31 may be a bias pattern for rotating the induction motor 21 at a low speed in the range where the car 5 is not started, that is, the range where the start shock is reduced due to oil leakage, as described above.

The input signal of the vector control circuit 31 is the torque command τ * of the ASR circuit 32 and the pulse encoder directly connected to the induction motor 21.
The signal 22a of 22 is the rotation speed ω _rM of the induction motor 21. The vector control circuit 31 has proportional constants K ₁ and K ₂ , a magnetic flux component I _m of the induction motor 21, a function And a function tan ^-1 (I _t / I _m ) and an adder.
The command i * of the current control circuit 30 includes a frequency command ω ₁ , a current command I _1, and a phase shift command θ. The frequency command ω ₁ is obtained by multiplying the torque command τ * by the proportional constant K ₁ to obtain the slip frequency ω _s . Next, the rotational frequency ω _rM is added to the slip frequency ω _s to obtain the frequency command ω ₁ . The current value command I ₁ and the movement command θ are
The torque command τ * is multiplied by the proportional constant K ₂ , and a function is obtained from the torque component I _t and the magnetic flux component I _{m of} the induction motor 21. And the function tan ^-1 (I _t / I _m ) respectively.

The current control circuit 30 obtains three-phase AC control signals i _u , i _v , i _w from the current command I *, controls the inverter 23, and rotates the induction motor 21.

The operation when switching from the start compensation command to the speed command to accelerate the elevator will be described. At the time t ₂ shown in FIGS. 4 and 5, the speed command ω _r1 rises in the speed command generation circuit, and at the same time, the normally open contact 41a ₁ is closed to operate the integral function, and the start compensation command τ is normally closed. The contact 41b ₁ opens and becomes zero.

During the start compensation command control, the speed command ω _r * of the ASR circuit 32 and the speed feedback signal ω
_rM is butted and a normally _open contact 41a ₃ is provided on the output side. This normally open contact 41a ₃ closes at time t ₂ and returns to the speed feedback control function.

At time t ₂ , the rotation speed ω _rM that is rotating with the start compensation command τ is stored. The _normally open contact 41a ₂ of the output of the speed memory circuit 36 is closed, and the start compensation rotation speed is set to the speed command ω _r1 that rises from zero. The command ω _r2 is added to form the rotation speed command ω _r * which is the input signal of the ASR circuit.

As a result, the ASR circuit 32 becomes a proportional-integral circuit that _uses the rotation speed ω _rM of the induction motor as a feedback signal, and the induction motor 21 follows the rotation speed command ω _r * to smoothly rotate the hydraulic pump.

In the above embodiment, the hydraulic pump 13 driven by the electric motor 21, the cylinder 3 for moving up and down the car 5 by the oil 13a discharged from the hydraulic hoop 13, and the speed command ω for the car 5
_The means 33 for generating _r1 and the speed command ω _r1 are used as the torque command τ *
To convert the torque command τ * into a current command i *, to rotate the electric motor 21 on the basis of the current command i *, and to start the motor according to the load at the time of starting. In the hydraulic elevator provided with means 34 for adding the compensation command τ as a torque command, means 22, TON2a ₂ for detecting the speed ω _r2 of the motor 21 rotated based on the start compensation command τ before the speed command ω _r1 rises. And this speed detection value ω _r2
And a means 36 for storing the stored speed detection value ω _r2 and means 35, 41a ₂ for superimposing the stored speed detection value ω _r2 on the speed command ω _r1 .

Further, the means 35, 41a ₂ for superposing the speed ω _r2 of the electric motor 21 rotated based on the start compensation command τ on the speed command ω _r1 is configured to be executed after the start compensation command τ is held at a certain value. There is.

Embodiments of the present invention will be described below.

(1) Although the current control circuit 30, the vector control circuit 31, the ASR circuit, the speed command generation circuit, the start compensation command circuit, and the speed memory circuit of the speed control device of this embodiment are described as separate circuits, This is a functional explanation, and when using a microcomputer, it is configured by software,
It is also possible to collectively configure the above functions.

(2) In FIG. 1, the hydraulic pump is driven by an induction motor via a belt, but a shaft direct connection or gear connection system may be used.

(3) In FIG. 1, the car 5 is directly moved up and down by the plunger 4, but it may be moved up and down indirectly along with the vertical movement of the passenger 4 via a rope.

(4) The load of the car 5 may be the output of the load detector provided under the car.

(5) The power converter including the converter 25 and the inverter 23 in FIG. 1 may be a current type.

〔The invention's effect〕

As described above, according to the present invention, it is possible to obtain a hydraulic elevator having a small starting shock and excellent deceleration control performance regardless of oil leakage in the hydraulic pump.

[Brief description of drawings]

1 is an overall configuration diagram showing an embodiment of the hydraulic elevator of the present invention, FIG. 2 is a diagram showing a schematic configuration of the speed control device of FIG. 1, and FIG. 3 is a detail of the speed control device of FIG. Figure, 4th
5 and FIG. 5 are views for explaining the conditions during the ascending and descending operations of the hydraulic elevator of FIG. 1, and FIGS. 6 (a) to 6 (e) are views for explaining the starting compensation command generating circuit according to the present invention, 7th
The figure is a sequence circuit diagram of the hydraulic elevator of FIG. 3 ... Cylinder, 4 ... Plunger, 5 ... Car, 11
...... Pulse encoder, 12 …… Solenoid switching valve, 13 …… Hydraulic pump, 14 …… Pressure detector, 21 …… Induction motor, 26 ……
Speed control device, 34 ... Start-up compensation command generation circuit.

Claims (2)

[Claims] 1. A hydraulic pump driven by an electric motor, a cylinder for raising and lowering a car by the oil discharged from the hydraulic hoop, a means for generating a speed command for the car, and a means for converting the speed command into a torque command. And a means for exchanging the torque command for a current command, a means for rotating the electric motor based on the current command, and a means for adding a start compensation command corresponding to a load at the time of starting as the torque command. In the above, before the speed command rises, means for detecting the speed of the electric motor rotated based on the start compensation command, means for storing the speed detection value, and the stored speed detection value for the speed command. And a means for superposing on the hydraulic elevator. 2. The means according to claim 1, wherein the means for superposing the speed of the electric motor rotated based on the start compensation command on the speed command is executed after the start compensation command is held at a certain value. Hydraulic elevator to.