JPH1087193A - Hydraulic elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic elevator having a larger live load irrespective of its higher lifted or lowered speed. SOLUTION: A plurality of hydraulic pumps 51 and 52 are connected in parallel to a hydraulic jack 4 by way of a hydraulic valve 7 and also to inverter-controlled electric motors 91 and 92. The parallel operation of the plurality of hydraulic pumps 51 and 52 correspondingly pluralizes the discharge quantity of oil to obtain a larger live load and a higher lifted or lowered speed. Control command signals outputted from a controller 11 establish a difference in the starting and landing timings of the plurality of electric motors 91 and 92 for smooth starting or landing in a lower discharge range. The provision of the valve 7 between the hydraulic pumps 51 and 52 and oil tanks 81 and 82 dispenses with correction in pressure conventionally required between the input and the output sides of the hydraulic pumps for smooth lifting or lowering operation with a simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic elevator.

[0002]

2. Description of the Related Art A conventional hydraulic elevator is configured as shown in FIG. 15 or FIG.

That is, first, as shown in FIG. 15, a car 1 is connected to one end of a rope 3 wound on a pulley 2, and the pulley 2 is configured to be supported by a plunger 4 a of a hydraulic jack 4. .

Accordingly, the hydraulic jack 4 is configured such that the pipe 61, the valve 7, the hydraulic pump 5, the other pipe 62, and the oil tank 8 are sequentially connected to the hydraulic jack 4 for raising and lowering the car 1. A three-phase AC power supply 12 is connected to an electric motor (induction motor IM) 9 that drives the motor 5 through an inverter device (INV) 10. The motor 9 is provided with a speed detector 9a, and the output signal is supplied to the elevator control device 11 as a speed feedback (FB) signal.

[0005] The control device 11 comprises a control unit for generating and supplying a speed command signal and a speed control device for controlling the ascending and descending operation of the car 1, and the speed control device transmits the speed command signal from the control unit and the speed control signal. Upon receiving a speed feedback signal or the like from the speed detector 9a, a control command signal for operation control is generated,
The drive is supplied to the inverter device 10 and the valve 7 for drive control.

Accordingly, the speed control device of the control device 11 has a speed detector 9a for forming the control command signal.
In addition to the speed feedback signal from the car 1, a car operation panel in the car 1, a speed detector 1a provided on the car 1 as shown in FIG.
, A stop switch 14, a load pressure sensor 6a, 6a provided in a pipe 61, and an oil temperature sensor 8 provided in an oil tank 8.
a and the like are supplied.

Generally, the speed control of the car 1 includes a rotation speed control method using an electric motor and a flow control method using a valve. FIG. 15 illustrates a case in which the speed of the car 1 is controlled by controlling the rotation speed of the electric motor 9 based on a control command signal from the control device 11. The control command signal from the control device 11 controls the rotational drive of the hydraulic pump 5 via the inverter device 10 and the electric motor 9, and the hydraulic oil from the hydraulic pump 5 pushes up the check valve of the valve 7, and the hydraulic jack 4 Pressed into the cylinder.

Further, at the time of descending operation, the control command signal from the control device 11 operates to open (turn on) the flow control valve (downward control valve) of the valve 7 by current control. As a result, the hydraulic oil in the cylinder in the pressurized state returns to the oil tank 8 via the pipes 61 and 62. At that time, the electric motor 9 rotates in the reverse direction due to the return of the hydraulic oil, and the electric power is regenerated.

In any case, the valve 7 shown in FIG.
Is composed of a check valve and a flow control valve, and has both a check function when operating hydraulic pressure is turned on and a flow control function from the cylinder by turning on / off current control.

However, the valve structure in the flow control system in which the hydraulic pump is driven by an AC motor having a constant rotation speed is composed of a check valve and a combination of an ascending and descending flow control valve. During the ascending operation, the hydraulic pump draws up the hydraulic oil from the oil tank, supplies it to the cylinder in the hydraulic jack through the check valve, and partially passes the oil tank from the oil return pipe through the ascending flow control valve. When the car descends, the descending flow control valve controls the return amount of hydraulic oil from inside the cylinder and returns to the oil tank.

In the rotation speed control system employing the inverter having the configuration shown in FIG. 15, it is necessary to adjust the pressure of the hydraulic oil before and after the valve in order to ensure a smooth start of the car.

More specifically, referring to FIG. 16 which shows a conventional hydraulic elevator of the rotation speed control type, when the car 1 is stopped, the valve 7 between the hydraulic jack 4 and the hydraulic pump 5 is stopped. The (check valve) is in a closed state, and the pressure of the hydraulic oil on the hydraulic jack 4 side is determined by the weight of the car 1 and the load, while the pressure on the hydraulic pump 5 side is substantially equal to the atmospheric pressure. Therefore, there is a large gap between the pressure on the hydraulic jack 4 side and the pressure on the hydraulic pump 5 side. In order to start the car 1 in this state, when the hydraulic pump 5 is operated, Due to the pressure difference between the outputs, a sudden and large vibration is generated in the car 1 and the ride comfort is greatly impaired. In FIG. 16, reference numeral 16 denotes a relief valve, and 63 denotes an oil return pipe.

Therefore, as described in Japanese Patent Application Laid-Open No. 3-106785, a first pressure detection is conventionally provided between the hydraulic jack 4 and the valve 7 in order to reduce the above-mentioned shock at the start. Device 15a, and a second pressure detector 15b between the valve 7 and the hydraulic pump 5, respectively.
The control device 1 is controlled so that the deviation between the two pressure detectors 15a and 15b is equal to or less than a predetermined value, that is, substantially equal.
1 controls the hydraulic pump 5.

However, when this control method is adopted, an oil leak phenomenon during the operation of the hydraulic pump 5 is unavoidable in the first place, and the difference in the amount of leakage due to the machine difference (instrument difference) of the hydraulic pump 5 is inevitable. is there. Therefore, the control device 11 has to adjust and control the pressure between the hydraulic pump 5 and the valve 7 in consideration of the machine difference (instrument difference) of the hydraulic pump 5, the oil temperature, the pressure, and the like.

In particular, at the time of starting the lowering of the car 1, in order to reduce the shock, the hydraulic pump 5 is once rotated in a direction opposite to the rotating direction at the time of lowering, the pressure is once increased, and then the speed control is performed. Therefore, it takes a considerable time from when the descending start command is output to when the car 1 actually moves to the descending operation.

Further, in the rotation speed control method as described above,
It is necessary to perform operation control while efficiently switching between pressure adjustment and traveling control in consideration of oil leakage of the hydraulic pump 5, and therefore, Japanese Patent Publication No. 64-311 and Japanese Patent Publication No.
As described in Japanese Patent Publication No. 312, a bias pattern (a pattern for rotating the hydraulic pump 5 in a range in which the car 1 does not move) and a traveling pattern (in order to rotate the hydraulic pump 5 in a range in which the car 1 moves). And a pattern in which the pattern is superimposed.

[0017]

As described above, in the conventional hydraulic elevator, whether the flow rate control system or the rotation speed control system is used, the maximum loading load and the maximum lifting / lowering speed are set as follows.
Although it depends on the oil discharge amount of the hydraulic pump, the maximum discharge amount of the hydraulic pump 5 is only about 500 liters / minute at the most, and improvement has been demanded in order to achieve a larger loading load and a higher speed.

In the flow control system in which the electric motor is always driven at a constant speed, the running of the elevator is controlled by on / off control of the flow control valve. It was easy and the ride was inevitable. Further, in the flow control method, since the starting current increases with the increase in the capacity of the electric motor, the power capacity of the entire elevator system increases, and there is a problem that the efficiency of the system configuration decreases.

Further, in a conventional hydraulic elevator, in order to reduce a shock at the time of starting, when controlling so that there is no pressure difference before and after the valve, the leakage flow rate of the hydraulic pump is controlled by the difference between the hydraulic pump and the temperature and pressure of the oil. Since it had to be considered in advance, much time was required for adjusting the hydraulic pump and the like. Also, when the car 1 descends, the hydraulic pump 5 is rotated in the opposite direction to the rotation at the time of descending, the pressure is once increased, and the speed control is performed. Therefore, after the descending start command is output, It takes a long time for the car 1 to actually start, and the car does not perform a quick descent start, resulting in reduced transport efficiency.

Further, even if the method of superimposing the bias pattern and the traveling pattern is adopted in the rotation speed control method, the bias pattern is compensated or corrected according to the oil temperature and pressure, and furthermore, the difference between individual hydraulic devices. Since the necessity arises, there is a drawback that the configuration and the adjustment are complicated.

[0021]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above circumstances, and a hydraulic elevator according to a first aspect of the present invention provides a hydraulic jack for supporting a car and one valve for the hydraulic jack. The pipes connected by providing are branched into a plurality of pipes, a plurality of hydraulic pumps respectively connected to the branched pipes, motors respectively connected to the plurality of hydraulic pumps, and control by these motors and valves. And a controller that generates and supplies a command signal and controls the car to move up and down in a predetermined speed pattern.

A hydraulic elevator according to a second aspect of the present invention provides a hydraulic jack for supporting a car, a plurality of valves arranged in parallel with a pipe connected to the hydraulic jack, and a plurality of valves corresponding to the plurality of valves, respectively. A plurality of hydraulic pumps connected to the piping, an electric motor respectively connected to the plurality of hydraulic pumps, and generating and supplying a control command signal to these electric motors and the plurality of valves; A control device for controlling the car to move up and down in a predetermined speed pattern.

As described above, according to each of the first and second aspects of the present invention, since a plurality of hydraulic pumps are configured to control one car, a large oil discharge amount can be obtained. Thus, it is possible to increase the load of the elevator and increase the speed.

In the hydraulic elevator according to the third aspect of the present invention, a hydraulic jack for supporting the car, a plurality of hydraulic pumps juxtaposed via pipes to the hydraulic jack, and the hydraulic pumps are respectively connected to the plurality of hydraulic pumps. An electric motor, an oil tank connected via a pipe provided with a valve capable of controlling a flow rate to each of the plurality of hydraulic pumps, and a control command signal generated and supplied to the electric motor and the plurality of valves; A control device for controlling the car to move up and down in a predetermined speed pattern.

As described above, according to the third invention, the valves are provided between the plurality of hydraulic pumps and the oil tank, respectively.
Even when the car is stopped, the pressure on the inlet side and the outlet side of the hydraulic pump can always be made equal to the pressure on the hydraulic jack side, and the pressure adjustment before and after the valve is unnecessary.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a hydraulic elevator according to the present invention will be described below in detail with reference to FIGS. The same components as those of the conventional configuration shown in FIGS. 15 and 16 are denoted by the same reference numerals, and detailed description is omitted.

FIGS. 1 to 5 are explanatory views showing a first embodiment of a hydraulic elevator according to the present invention. That is, in FIG. 1, a pipe 61 is connected to the hydraulic jack 4 that supports the car 1, and the pipe 61 is connected to one valve 7 and is branched afterward.
2. Oil tanks 81, 8 through other pipes 62, 62 sequentially
2 are connected. A load pressure sensor 6a is mounted on a pipe 61 between the hydraulic jack 4 and the valve 7,
Oil tanks 81 and 82 have oil temperature sensors 81a and 82a, respectively.
a is provided. But oil tank 8
1 and 82 may be common and may be configured as one.

As described above, a plurality (two) of hydraulic pumps 51 and 52 are connected to the hydraulic jack 4 via one valve 7.
Motors 91 and 92 are connected to the hydraulic pumps 51 and 52, respectively.
The first and second hydraulic pumps 51 and 52 are individually driven to rotate. Therefore, in this hydraulic elevator, the hydraulic jack 4 can be operated with an oil discharge amount that is a multiple of the discharge amount per unit (two times) by the parallel operation of the two hydraulic pumps 51 and 52.

Inverters 101 and 102 are connected to the motors 91 and 92, respectively.
The electric motor 91 detected by each speed detector 91a, 92a,
The rotation speed information of the controller 92 is used as a speed feedback signal.
Is supplied to the speed control device inside the vehicle. Therefore, the speed control device generates a control command signal for controlling the rotation of the electric motors 91 and 92 corresponding to the inverter devices 101 and 102, and a control command signal for controlling the opening and closing of the down control valve for the valve 7, respectively. The car 1 is supplied, and the operation and speed control of the car 1 are performed.

As shown in FIG. 2, the control device 11 comprises a microcomputer 111 mounted thereon, inverter drive circuits (INV drives A and B) 112a and 112b, and a valve drive circuit (valve drive) 113. Is done. The inverter drive circuits 112a and 112b receive speed feedback signals from the speed detectors 91a and 92a, respectively, and the valve drive circuit 113 receives the oil temperature sensor 81
a, 82a, a load pressure signal from the load pressure sensor 6a, and a car speed signal from the speed detector 1a of the car 1 are supplied.

The microcomputer 111, together with the inverter drive circuits 112a and 112b and the valve drive circuit 113, receives a speed feedback signal from the speed detectors 91a and 92a as described above and generates a speed pattern as a control command signal. The speed pattern is supplied to the corresponding inverter devices 101 and 102 via inverter drive circuits 112a and 112b, and is supplied to and controlled by the valve 7 via the valve drive circuit 113, respectively.

The lifting operation control method of the hydraulic elevator shown in FIGS. 1 and 2 will be further described with reference to a speed pattern diagram of FIG. 3 and a control operation flowchart of FIG.

That is, the motors 91,
FIG. 3 shows a speed pattern supplied to drive and control the valve 92 and the valve 7, and a speed pattern of the car 1 itself which is moved up and down based on the speed pattern.
(B), (c) and FIG. 3 (a).

FIG. 3A shows the speed pattern of the car 1 of the hydraulic elevator. The car 1 reaches the rated speed of 2 A (m / min) and reaches the rated speed after starting. This indicates that the vehicle travels at an acceleration / deceleration of ² B (m / sec ² ) from the rated speed to the landing mode.

In order to realize the acceleration / deceleration of the rated speed 2A (m / min) and the acceleration 2B (m / sec ² ), in this embodiment, the speed patterns of the motors 91 and 92 are shown in FIG. 3 (b) and (c), the speed pattern of the car 1 (FIG. 3)
In contrast to (a)), the speed patterns are configured to have a half speed (A) and a half acceleration / deceleration (B), respectively. In other words, in other words, each of the electric motors 91 and 9
By combining the speed patterns 2 (FIGS. 3B and 3C), the speed pattern of the car 1 (FIG. 3A) is obtained. At least during operation at the rated speed,
The amount of oil discharged to the hydraulic jack 4 is determined by the parallel operation of the electric motors 91 and 92, with the sum of the respective discharged amounts of the hydraulic pumps 51 and 52, that is, twice the oil discharged.
Is driven.

Therefore, referring to the flowchart of FIG.
The procedure for generating and supplying the speed pattern in the control device 11 will be described in detail below. That is, in FIG. 4, (1) First, the car 1 is allowed to rise (fall) (YES).
(Step S1), the control device 11 first determines whether or not to permit one of the inverter devices 101 to output a speed pattern (step S2).

(2) In step S2, when the output of the speed pattern is permitted to one of the inverter devices 101 (YES), the control device 11 starts the operation of the inverter device 101 starting at the timing T0 shown in FIG. The speed pattern shown in FIG. 3B is output to the electric motor 91 via the motor (step S3). The acceleration at the start at this time is B (m / sec ² ).

In steps S1 and S2,
When there is no ascent (descent) permission and speed pattern output permission (N
O) ends.

(3) Next, the controller 11 controls the car 1
It is determined whether or not the ascending (falling) start has been completed (step S4).

(4) When the control device 11 determines that the start of the car 1 has been completed (YES), the control unit 11 sets the timing pattern shown in FIG. Output to the electric motor 92 via the device 102 (step S5).

That is, in the speed pattern at the time of starting the car 1, the other electric motor 92 starts to be started at a delayed (delayed) timing T1 with respect to the start timing T0 of the one electric motor 91. Therefore, since the start of the car 1 is performed by one of the electric motors 91, the hydraulic jack 4 is controlled accurately with a low discharge region of the hydraulic oil, and a smooth and quick running start is performed. .

Thereafter, after the timing T1, the motor 92
Is started, and the rotation of the electric motor 91 is added, so that the car 1 has a rated speed of 2 A (m / mi).
In order to reach n), the vehicle is accelerated at a speed of 2B (m / sec ² ) between timings T1 and T2.

However, during the operation until the timing T5 when the car 1 enters the landing mode after the start, the acceleration / deceleration control can be appropriately performed individually by the inverter control. For example, when entering the deceleration state from timing T3 to T4 in the speed pattern shown in FIG. 3, one of the motors 91 is started prior to the start of deceleration of the other motor 92 (timing T4).
By controlling the speed of the car 1 at an earlier timing T3, the discharge amount control is smoothly performed, and the car 1 is smoothly decelerated.

(5) Next, after operation at the rated speed, the control device 11 determines whether or not it is in the landing mode (step S6). In the case of the landing mode (YES), the control device 1
The output of the speed pattern from FIG. 1 (FIG. 3 (b)) becomes zero at timing T5, and one motor 91 stops (step S7). If not in landing mode here (NO)
In this case, the process returns to step S3.

(6) After the landing mode, the controller 1
1 judges whether the car 1 will land on the next floor (step S8). If it is determined that the landing is performed here (YES),
The output of the speed pattern shown in FIG.
, The other motor 92 also stops, and the car 1 stops as shown in FIG. 3A (step S9). Note that it is not determined in step S8 that the vehicle is landing on the next floor (N
O) In case of, return to step S5 and again the two electric motors 91,
The rotation operation of 92 continues.

That is, in the speed pattern of the car 1 in the landing mode, the other electric motor 92
Since the operation is delayed (delayed) and stopped during the period from the timing T5 to T6, the operation control by one motor is performed at the time of landing as well as at the time of starting, and the hydraulic oil operates in the low discharge region, so that the accuracy is high. The control is performed, and the car 1 can smoothly and quickly land on the floor.

If two motors 91, 9
In order to perform the start-up of the hydraulic pumps 51 and 52 at the same time as in the parallel operation and to perform the start-up smoothly and quickly as in the case of the delay operation, the oil discharge amount in the low discharge area of the hydraulic pumps 51 and 52 is divided by two minutes. The hydraulic pumps 51 and 52 are required to rotate at a lower speed. However, further low-speed rotation of the hydraulic pumps 51 and 52 results in a larger amount of oil leakage, which is not preferable because good control cannot be performed. This phenomenon is the same in the landing mode. This also applies to the case where two power units are connected in a flow rate control method different from the rotation speed control method, and both the built-in motors perform start-up and landing control in a constant-speed rotation state. I can say.

The control of the inverter devices 101 and 102 by the control command signals of the respective speed patterns and the like described above is described with reference to FIG.
The control procedure which is performed in the control device 11 having the configuration shown in FIG. 3 and executed mainly by the microcomputer 111 will be described with reference to the flowchart of FIG. That is, (1) In the ROM and the like in the microcomputer 111 of the control device 11, data on the number of motors 91 and 92 and various data for creating a speed pattern are set in advance. Therefore,
The speed pattern calculation means in the microcomputer 111 creates a speed pattern based on the number data of the electric motors 91 and 92 and other various data for creating the speed pattern (step S21).

(2) Next, similarly, the R
The pattern delay time is set in advance in the OM or the like, and the speed pattern output switching means in the microcomputer 111 includes the speed pattern from the speed pattern calculation means and the switching information from the speed pattern delay creating means in the microcomputer 111 as well. And a switching signal corresponding to each of the electric motors 91 and 92 is derived (step S22).

(3) Then, a switching signal corresponding to the electric motors 91 and 92 is output from the speed pattern output means (step S23), and the speed control means in the microcomputer 111 outputs the speed feedback signals from the speed detectors 91a and 92a, Then, a speed feedback signal from the car 1 is introduced, and a control command signal corrected so as to operate in accordance with a predetermined speed pattern is generated and supplied to each of the inverter devices 101 and 102 (step S24).

As described above, the control device 11 generates a control command signal and controls the supply to each of the inverter devices 101 and 102.

In the above description, the inverter device 10
Although the supply control of the control command signal to the control valves 1 and 102 has been described, the opening and closing control of the valve 7 is controlled by controlling the rotation speed of the hydraulic pumps 51 and 52 when the car 1 moves upward, as in the related art. Pushes up the check valve of valve 7,
The hydraulic oil is discharged into the cylinder of the hydraulic jack 4, and at the time of descending operation, the hydraulic oil is supplied from the oil tanks 81 and 82 by turning on the current control for the flow control valve (downward control valve) based on the control command signal from the control device 11. To reflux. At this time, each of the electric motors 91 and 92 reversely rotates due to the return of the hydraulic oil from the cylinder.

As described above, in the hydraulic elevator according to the first embodiment, first, in order to obtain good starting and landing control, from the time of starting (timing T0) to timing T1, and in the landing mode. Inverter control by one of the motors 91 (or the motor 92) is performed between the timing T5 and the timing T6, and the two motors 91 and 92 are operated during the rated speed operation from the timing T1 to the timing T5. Hydraulic pump 51,
By the variable speed control of 52, the operation is performed with the total output of each of the motors 91 and 92, that is, the oil discharge amount twice as large as that of one motor, so that a large load and a high speed can be achieved.

As in this embodiment, the speed patterns (FIGS. 3 (b) and 3 (c)) given from the control device 11 to the electric motors 91 and 92 are the same except for the timing of starting the command. Since the speed pattern of the shape is indicated, it is possible to simplify the calculation operation for forming the control command signal in the control device 11.

In this embodiment, the motors 91,
Although 92 and two and two inverter devices 101 and 102 are provided, respectively, the piping 61 is configured to have three branches or more, and three or three or more devices are provided, respectively, and three or three or more devices are provided. May be configured to be controlled by the control device 11. In this case as well, the control device 11 forms and supplies a speed pattern so that the start and landing are controlled with a timing difference (delay) between the plurality of inverter devices, so that the control device 11 is also smooth. Starting and landing operations become possible.

In the first embodiment, as shown in FIG. 1, a single valve 7 is connected to the pipe 61, and the hydraulic pump 51 is branched by branching the pipe 61 on the hydraulic pump side. 52, a plurality of valves are provided in a pipe 61 branched in advance, and a plurality of hydraulic pumps 5 are provided.
1, 52 may be connected.

FIGS. 6 and 7 are diagrams showing a second embodiment of a hydraulic elevator in which a plurality of valves are provided so as to correspond to the plurality of hydraulic pumps 51 and 52, respectively. The difference is that they control 71 and 72,
The other main parts are the same as those of the first embodiment, and only the parts that are particularly different will be described.

That is, as shown in FIG. 7, the control device 11 comprises a microcomputer 111 and an inverter drive circuit 112.
a, 112b and a valve drive circuit (valve drive A,
B) 113a and 113b, and the inverter drive circuits 112a and 112b receive the speed feedback signals from the speed detectors 91a and 92a and the valve drive circuit 113a, respectively, in the same manner as in the first embodiment. , 113b
Correspond to the oil temperature signals from the oil temperature sensors 81a and 82a, the load pressure signal from the load pressure sensor 6a,
And a car speed signal from the speed detector 1a of the car 1 is supplied.

The microcomputer 111 has speed detectors 91a, 9
2a, a speed pattern as a control command signal is generated by receiving a speed feedback signal or the like from the inverter drive circuit 112a,
The corresponding inverter devices 101 and 102 from 112b
The valve driving circuits 113a and 113b are configured to control the valves 71 and 72 in a corresponding manner.

The hydraulic elevator shown in FIG. 6 and FIG.
As described above, the valves 7 corresponding to the respective hydraulic pumps 51 and 52 are provided.
The control device 11 controls the valves 71 and 72 individually so that the control device 11 controls the inverter devices 101 and 102, respectively.

Accordingly, the lifting operation control of the hydraulic elevator is also the same as that described with reference to the speed pattern diagram of FIG. 3 shown in the first embodiment and the flowchart of the control operation of FIG. In the mode, only one of the motors operates to enable smooth starting and landing in the low discharge area, and the speed 2 during rated operation.
A (m / min) rated speed, and acceleration / deceleration of acceleration 2B (m / sec ² ) between the timing T1 and T2 and the timing T3 and T5 after the start, increase of the load and high speed of operation. Can be realized. The microcomputer 1
The control procedure centered on 11 is the same as in the first embodiment shown in FIG.

As described above, also in the hydraulic elevator according to the second embodiment, the control device 11 controls the two electric motors 91 and 92 and the two hydraulic pumps 51, 52 and 2 respectively.
Since a plurality of hydraulic valves 71 and 72 are controlled, a plurality of oil discharge amounts can be obtained, a large load capacity and a high speed operation can be achieved, and at the same time, each configuration has a delay. , The hydraulic jack 4 is supplied with a single hydraulic pump in a low discharge area in a low discharge area and landing, thereby enabling smooth control during startup and landing.

The first and second parts shown in FIG. 1 and FIG.
In the embodiment, two motors 91 and 92 are provided (two or more). However, the motors 91 and 92 can be replaced with one motor.

FIG. 8 is a block diagram showing a third embodiment of the hydraulic elevator according to the present invention, wherein two (a plurality of) hydraulic pumps 51 and 52 are controlled by one motor 91. did. The one electric motor 91 receives a control command signal from the control device 11 and controls by inverter control so that only one of the two hydraulic pumps 51 and 52 is operated or both are operated at the same time. The device 11 has correspondingly two valves 7
1, 72 are controlled to open and close.

In the third embodiment, the car 1 is constructed as described above, and the car 1 is provided with two (a plurality of) hydraulic pumps 5.
Since the operation control is performed at 1, 52, the first and second
In the same manner as in the embodiment, it is possible to increase the load and smoothly perform the starting and landing operations.

In each of the first, second and third embodiments having the configuration shown in FIGS. 1, 6 and 8, each of the two motors 91 and 92 is controlled by an inverter. Although described, the inverter control may be performed for only one of them.

FIG. 9 is a block diagram showing a fourth embodiment of a hydraulic elevator according to the present invention, in which only one (motor 91) is controlled by an inverter, and the other (motor 92) is driven by constant speed rotation. The connected hydraulic pump 53 was of a constant discharge type. As described above, the hydraulic elevator according to the present embodiment is configured by combining the electric motor 91 which performs speed control by the rotation speed control method by the inverter and the electric motor 92 by the constant speed rotation flow control method. While improving the running performance at the time of starting and landing. In FIG. 9, reference numeral 63 denotes a pipe for returning oil.

As described above, the hydraulic elevator according to the present embodiment includes a plurality of hydraulic pumps 51 and 53, and a control command signal from the control device 11 is transmitted to the electric motor 91 for driving at least one hydraulic pump 51. Since it is supplied to the vehicle, control at the time of starting and landing is smoothly performed, and a stable traveling characteristic with good riding comfort and high landing accuracy is obtained.

In any case, the hydraulic elevator according to each of the above-described embodiments can be configured with a plurality of hydraulic pumps to achieve a large discharge amount, and at least one hydraulic pump among them can be controlled by a rotational speed control system using an inverter. As a result, for the first time, operations at the time of starting and landing are performed smoothly, and at the same time, efficient use of the power supply capacity and energy saving are made possible.

Next, in the double unit system under the inverter control, by arranging the hydraulic valve between the hydraulic pump and the oil tank, complicated pressure adjustment between the valve input and output required at the time of starting the descending of the car is performed. It becomes unnecessary, and a smooth descent start can be made possible.

FIG. 10 is a configuration diagram showing a fifth embodiment of the hydraulic elevator according to the present invention. This fifth embodiment is different from the configuration of the second embodiment shown in FIG. By providing the valves 71 and 72 between the respective hydraulic pumps 51 and 52 and the common oil tank 8, it is not necessary to adjust the pressure between the valve input and output at the time of starting.

That is, each of the valves 71 and 72 has two functions of a check valve and a flow control valve (down control valve). The opening of the flow control valves of the valves 71 and 72 is determined accordingly. In FIG. 10, reference numerals 121 and 122 denote relief valves, respectively.

The control operation of the hydraulic elevator according to the fifth embodiment will be described in detail with reference to FIGS. In the following description, each of the valves 71 and 72 will be described.
Since the same operation is performed, the operation of the system of one valve 71 will be mainly described, and the description of the operation of the system of the other valve 72 will be omitted.

11 (a) and 11 (b) show the flow characteristics of the flow control valve (down control valve) in the valve 71. The control value of the control command signal from the control device 11 is now applied to the valve 71. When VI is given, the flow rate QV is output from the valve 71. When the command value VI is zero, the valve 71 as well as the check valve is closed, the valve flow is not obtained, and the hydraulic elevator is in a stopped state. In this state, the load pressure is applied to the valve 71.

Then, as shown in FIG. 11B, a command value VI is given to the valve 71, and the command value VI is supplied to the valve VIS.
At time t, the oil starts to flow by opening the flow control valve of the valve 71, and when the command value VI is further increased, the flow rate is increased substantially linearly according to the magnitude of the command value VI. When the command value VI becomes VIH, the flow rate becomes QVH, and the flow control valve of the valve 71 is fully opened. Therefore, even if the command value VI is further increased, the flow rate does not change.

Therefore, when the ascending operation is started from the stopped state of the car 1 and the flow rate is controlled by controlling the rotation speed of the hydraulic pump 51, the check valve of the valve 71 is fully opened.

That is, to explain the operation of the elevator car 1 during the ascending operation, when the elevator ascending operation command is output from the control device 11 to the inverter device 101 and the valve 71, first, the electric motor 91 starts rotating, and at the same time, Valve 71
Is opened. At this time, since no pressure difference occurs between the input and output of the hydraulic pump 51, no shock occurs at the time of starting.

Thereafter, the number of revolutions of the electric motor 91 is controlled in accordance with a speed reference based on the speed pattern generated by the control device 11, whereby the amount of oil discharged from the hydraulic pump 51 is controlled and the plunger of the hydraulic jack 4 is controlled. 4a is operated, and the ascending operation of the car 1 is performed.

Then, after the elevator is stopped, when the controller 11 outputs a lowering operation command, the flow control valve of the valve 71 is gradually opened, and the oil from the hydraulic jack 4 is released from the hydraulic pump. The fluid is returned to the oil tank 8 via the valve 71 while the electric motor 91 is rotated in the reverse direction via 51. Also at this time, since there is no pressure difference between the input and output of the hydraulic pump 51, no shock is generated at the time of the descent start.

In this manner, the amount of oil discharged from the hydraulic pump 51 is controlled by controlling the reverse rotation speed of the electric motor 91 in accordance with the speed reference based on the speed pattern generated by the control device 11, and the car 1 descends. Operation is controlled.

Next, the operation of raising and lowering the hydraulic elevator will be described in detail with reference to FIG. 12 showing an operation sequence at the time of raising the hydraulic elevator and FIG. 13 showing an operation sequence at the time of lowering. explain.

First, the operation sequence when ascending is as shown in FIG.
In FIG. 12A, when the control device 11 generates the rising direction selection signal DIR <U>, as shown in FIG. 12B, the operation permission signal PMC of the hydraulic pump 51 is generated after the lapse of the time tPMS. The hydraulic pump 51 starts rotating by the operation permission signal PMC.

Next, as shown in FIG. 12 (c), the valve operation permission signal VLE generated in the control device 11
Is generated and supplied after the time tPMRS elapses after the generation of the operation permission signal PMC of the hydraulic pump 51, and the valve 71 is fully opened. That is, the control current VIH for fully opening the valve 71 is supplied from the control device 11 to the valve 71 at the timing shown in FIG.

As described above, the valve 71 is fully opened immediately after the start-up, the flow rate is controlled by the hydraulic pump 51, and the speed of the car 1 is controlled. When a command for decelerating and stopping after traveling based on a predetermined speed is output, first, as shown in FIG.
E is released and becomes zero, and after the time t PME, FIG.
The operation permission signal PMC is released as shown in (b), and the rising direction selection signal DIR <U> is released as shown in FIG.

The above is the operation sequence when ascending,
The operation sequence at the time of falling is substantially the same as when the falling direction selection signal DIR <D> is generated in FIG.
As shown in FIG. 13D, the valve operation permission signal VLE
Is generated, the flow control valve of the valve 71 starts to open, and oil recirculation from the hydraulic jack 4 side to the oil tank 8 is started.

Therefore, as shown in FIG. 13B, an operation permission signal PMC for the hydraulic pump 51 is generated after a lapse of time tPME after the generation of the valve operation permission signal VLE, and further, after a delay of time tPMRS, the hydraulic pump 51 Starts spinning. The flow control function shifts from the valve 71 to the hydraulic pump 51 only after a predetermined time has elapsed since the hydraulic pump 51 started rotating. Therefore, the flow rate control is performed by the hydraulic pump 51.
After the shift to, the control device 11 supplies a control current VIH as shown in FIG. 13 (e) to the valve 71, and the valve 71 is fully opened. As described above, in this embodiment, at the beginning of the descent start, the flow rate is controlled by the valve 71 first, then the valve 71 is fully opened, and the speed control of the car 1 is performed by the flow rate control of the hydraulic pump 51. The occurrence of the shock operation of the hydraulic pump 51 at the time of the descent start is avoided.

Next, after traveling based on a predetermined speed by the flow rate control of the hydraulic pump 51, after decelerating and stopping, FIG.
, The valve operation permission signal VLE is released,
After the elapse of the time tPME, the operation permission signal PMC is sent as shown in FIG.
As shown in (b), the descending direction selection signal DIR <D> is released and stopped.

Next, a processing procedure inside the control device 11 for performing the above-described operation sequence and speed control will be described with reference to FIG. In FIG. 14, Vref is a target speed reference,
Vplg indicates the actual speed of the car 1, and in the present embodiment, the signal from the speed detector 1a installed in the car 1 is used as the actual speed.

First, when performing the lift control of the hydraulic elevator, the control device 11 performs the operation sequence at the time of starting described with reference to FIG. 12, and thereafter, a deviation between the target speed reference Vref and the actual speed Vplg of the car 1. The electric motor 91
To control the number of revolutions. At this time, the hydraulic pump 51 cannot avoid a slight oil leak due to its characteristics, and there is an area where the car 1 does not immediately move even when the hydraulic pump 51 is rotated, so that the starting control and the traveling control are efficiently performed. Therefore, it is possible to start the speed control after operating the valve 71 and the hydraulic pump 51 in a predetermined operation sequence. Therefore, pressure adjustment at the time of starting is not required.

That is, if there is a deviation between the speed reference Vref and the actual car speed Vplg due to the leakage of the hydraulic pump 51, the control device 11 adjusts the rotation speed of the electric motor 91. Therefore, there is no need to overlap the bias pattern and the running pattern as in the related art.

When the hydraulic elevator is controlled to descend, the flow rate is controlled by the valve 71 at the time of starting.
It is necessary to output a command from the control device 11 to the hydraulic pump 51 together with a command to the valve 71, but other processes are the same as in the ascent control.

In the above description, the valve 71, the hydraulic pump 51 and the electric motor 91 which constitute one (one) are described, but the valve 72 and the hydraulic pump 52 which constitute the other (one).
The same is true for the motor 92, and the present invention can be applied to a configuration of three or more motors. Further, with two units, only the electric motor is used as a common unit as shown in FIG.
The opening and closing operation of the valves 71 and 72 causes the hydraulic pump 51,
The switching control of 52 may be performed.

In the fifth embodiment, two motors 91 and 92 and two valves 71 and 72 are simultaneously controlled. However, like in the first and second embodiments, the starting is performed. Only one motor and valve can be controlled at the time of landing or landing to smooth the operation at the time of starting and landing. Energy saving can be achieved.

In the fifth embodiment, when a plurality of devices are used as in the fourth embodiment shown in FIG. 9, it is not always necessary to control all the motors by inverter control. Alternatively, a combination of a low discharge rate type by constant rotation of the motor and a speed correction type by inverter control may be adopted.

As described above, the fifth embodiment has a simple configuration in which the valve capable of controlling the flow rate is connected between the hydraulic pump and the oil tank, and is used when the car of the hydraulic elevator is stopped. In addition, the pressure on the inlet and outlet sides of the hydraulic pump can always be almost equal to the pressure of the hydraulic jack, and the variation in equipment between the hydraulic cylinder side and the hydraulic pump side at the time of conventional startup is also considered. There is no need to perform complicated pressure adjustment, and the start-up time is reduced, enabling smooth and rapid operation.

As described above, the hydraulic elevator according to the present invention can provide a large discharge amount by controlling a plurality of electric motors and hydraulic pumps in one car to control the electric motor. By using an inverter for control and using variable speed control of a hydraulic pump, it is possible to improve running characteristics from start to landing, and to achieve power supply capacity and energy saving during running.

[0097]

According to the hydraulic elevator of the present invention, a plurality of hydraulic pumps are provided in one car to obtain a large discharge amount, and at least one electric motor employs inverter control or the like, and is controlled by a control command signal. By performing the variable speed control of the hydraulic pump, it is possible to increase the maximum loading load, improve the running characteristics at the time of starting and landing, and achieve the power source capacity and energy saving during running.

Further, the hydraulic elevator of the present invention has a simple structure in which a valve is arranged between a hydraulic pump and an oil tank, so that even when the car of the hydraulic elevator is stopped,
Since it is possible to control both the inlet and outlet sides of the hydraulic pump to be equal to the pressure of the hydraulic jack, complicated pressure adjustment operations of the hydraulic cylinder and hydraulic pump at startup are not required, and the start-up time is reduced. Shortening is now possible.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a hydraulic elevator according to the present invention.

FIG. 2 is a configuration diagram of a control device of the hydraulic elevator shown in FIG.

FIG. 3 is a speed pattern diagram output from the hydraulic elevator control device shown in FIG. 1;

FIG. 4 is a flowchart showing a control for raising and lowering the hydraulic elevator shown in FIG. 1;

FIG. 5 is an operation flowchart of the control device shown in FIG. 2;

FIG. 6 is a configuration diagram showing a second embodiment of the hydraulic elevator according to the present invention.

FIG. 7 is a configuration diagram of a control device for the hydraulic elevator shown in FIG. 6;

FIG. 8 is a configuration diagram showing a third embodiment of a hydraulic elevator according to the present invention.

FIG. 9 is a configuration diagram showing a fourth embodiment of a hydraulic elevator according to the present invention.

FIG. 10 is a configuration diagram showing a fifth embodiment of a hydraulic elevator according to the present invention.

FIG. 11 is an explanatory view of the operation of the valve of the hydraulic elevator shown in FIG. 10;

12 is a control timing chart when the hydraulic elevator shown in FIG. 10 is raised.

FIG. 13 is a control timing chart when the hydraulic elevator shown in FIG. 10 is lowered.

14 is an explanatory diagram showing a control system of the hydraulic elevator shown in FIG.

FIG. 15 is a configuration diagram of a conventional hydraulic elevator.

FIG. 16 is a configuration diagram of another conventional hydraulic elevator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Riding car 1a Speed detector 4 Hydraulic jack 5,51,52,53 Hydraulic pump 61,62,63 Piping 6a Load pressure sensor 7,71,72,73 Valve 8,81,82 Oil tank 9,91,92 Electric motor 10, 101, 102 Inverter device 11 Control device 12 AC power supply 15a, 15b Pressure detector 16 Relief valve

Claims (9)

[Claims] 1. A hydraulic jack for supporting a car, and a plurality of hydraulic pumps each connected to the branched pipe by branching a pipe connected to the hydraulic jack by providing one valve. An electric motor connected to each of the plurality of hydraulic pumps, and a control device that generates and supplies a control command signal to these electric motors and valves, and controls the car to move up and down in a predetermined speed pattern. A hydraulic elevator comprising: 2. The hydraulic elevator according to claim 1, wherein the control device is configured to individually control the plurality of electric motors via an inverter device. 3. A hydraulic jack for supporting a car, a plurality of valves juxtaposed to a pipe connected to the hydraulic jack, and a plurality of valves connected to the pipe so as to correspond to the plurality of valves, respectively. Hydraulic pumps, electric motors respectively connected to the plurality of hydraulic pumps, and generating and supplying control command signals to these electric motors and the plurality of valves, whereby the car moves up and down in a predetermined speed pattern. And a control device for controlling the hydraulic elevator. 4. The hydraulic elevator according to claim 3, wherein the control device is configured to individually control the plurality of electric motors via an inverter device. 5. The hydraulic elevator according to claim 4, wherein the control command signal supplied from the control device to each of the plurality of electric motors has a different drive timing. 6. The electric motor according to claim 4, wherein the plurality of electric motors are controlled by the control device such that the car operates at a substantially rated speed during parallel operation.
The hydraulic elevator as described. 7. The control device controls the plurality of electric motors such that only one of the plurality of hydraulic pumps is in an operating state when the car is started or when the car arrives on the floor. The hydraulic elevator according to any one of claims 4 to 6, wherein 8. The motor is constituted by a plurality of motors so as to be connected to the plurality of hydraulic pumps, and at least one of the plurality of motors is controlled at a variable speed via an inverter device. 2. The hydraulic elevator according to claim 1, wherein the other electric motor drives the corresponding hydraulic pump at substantially the rated speed rotation. 9. A hydraulic jack supporting a car, a plurality of hydraulic pumps juxtaposed via a pipe to the hydraulic jack, an electric motor respectively connected to the plurality of hydraulic pumps, An oil tank connected to a hydraulic pump through a pipe provided with a valve capable of controlling a flow rate, a control command signal generated and supplied to the electric motor and the plurality of valves, and the car is driven at a predetermined speed. A hydraulic elevator, comprising: a control device for performing control to move up and down in a pattern.