JPH0859126A - Hydraulic drive device and hydraulic elevator - Google Patents

Abstract

PURPOSE: To prevent extension of an accident by detecting slippage of a belt wound around between a drive motor and a hydraulic pump. CONSTITUTION: A standard value of an electric current of a drive electric motor 11 by a load of a hydraulic cylinder 3, temperature of working oil 9 of an oil tank 7 and oil temperature of a deliver pipe 14A is previously inputted against a microcomputer 23 of a control device 20. Existence of slippage of a V belt 12 is detected by providing a current transformer on the side of an electric power source of the drive electric motor 11, inputting a signal of the electric current of the drive electric motor 11 detected by this current transformer to the control device 20 through an analog-to-digital converter 22 and comparing the previously input standard value.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art FIG. 5 is a longitudinal sectional view of a building in which a conventional direct hydraulic elevator is installed. In FIG. 5, a low-rise building 17 is adjacent to the lower part of the hoistway 1 provided at one corner of a high-rise building where a hydraulic elevator is installed, and inside the machine room 5 provided under the building 17. A hydraulic unit whose details will be described later is installed in the.

Of these, a cylinder portion of the hydraulic cylinder 3 is embedded in a pit 1a formed at the lower end of the hoistway 1 shown on the right side. A car 4 is placed on the upper end of the rod portion 3 a of the hydraulic cylinder 3.

Guide rails 2 are vertically laid on opposing walls of the hoistway 1 in a direction orthogonal to the plane of the drawing, and a plurality of unillustrated cars provided above and below a car 4 are provided on the top and both side surfaces of the guide rail 2. The guide roller is pressed. In the hoistway 1, a landing gate 18 is shown on the right side in FIG. On the other hand, a pedestal 6 made of shaped steel is installed on the floor of the machine room 5, and an oil tank 7 for storing hydraulic oil 9 is placed on the upper surface of the pedestal 6.

Of these, a hydraulic pump 10 is installed at the center of the bottom of the frame 6. A drive motor 11 is arranged in parallel on the left side of the hydraulic pump 10, and the output shaft of the drive motor 11 is wound around the left end of a V-belt 12.
The right end of is wound around a pulley inserted into the end of the rotary shaft protruding from the hydraulic pump 11. A flow rate control valve 15 is provided above the hydraulic pump 10, and a suction port of the flow rate control valve 15 is connected to a discharge port of the hydraulic pump 10 by a pipe.

A filter 8 is housed in the center of the oil tank 7. An upper end of a suction pipe 13 is connected to the outflow side of the filter 8, and the suction pipe 13 penetrates a bottom plate of the oil tank 7 and is connected to a suction port provided at an upper portion of the hydraulic pump 10.

The discharge port on the left side of the flow control valve 15 is a discharge pipe 14
Is connected to the connection port of the bottom plate on the left side of the oil tank 7, and the discharge port on the right side of the flow control valve 15 is connected to the upper end of the cylinder portion of the hydraulic cylinder 3 via the discharge pipe 14A.

An air-cooled radiator 16 is provided above the oil tank 7, and a radiator fan 16a is housed on the left side of the radiator 16. The radiator 16 is provided with a hydraulic pipe through which the hydraulic oil 9 stored in the oil tank 7 circulates. A ventilation port 5a is formed in the wall of the building 17 on the left side of the heat radiation fan 16a in advance.

In the hydraulic elevator constructed as described above, when the drive motor 11 drives the hydraulic pump 10, the working oil 9 stored in the oil tank 7 is passed from the filter 8 to the suction pipe 13
Is sucked into the hydraulic pump 10 via the. A part of the hydraulic oil sucked and discharged from the discharge port on the other side of the hydraulic pump 10 is supplied to the hydraulic cylinder 3 through the discharge pipe 14 to raise the rod portion 3a of the hydraulic cylinder 3.

When the car 4 rises and approaches a predetermined floor as the rod portion 3a rises, the flow rate of the hydraulic oil 9 discharged from the flow control valve 15 decreases and the car decelerates. When the car reaches a predetermined position, the hydraulic oil 9 discharged from the flow control valve 15 is stopped, and the hydraulic oil 9 discharged from the hydraulic pump 10 is entirely returned to the oil tank 7 via the discharge pipe 14.

On the other hand, when the car 4 is stopped, the hydraulic oil discharged from the hydraulic pump 10 returns from the discharge port to the oil tank 7 via the flow rate adjusting valve 15 and returns to the oil tank 7 by so-called bleed-off operation. Return to.

When the car 4 descends, the flow rate of the working oil 9 in the cylinder portion of the hydraulic cylinder 3 is controlled by the flow rate adjusting valve 15 whose valve angle is controlled, and the oil tank 7 is passed through the discharge pipe 14. Is recirculated to the drive motor.
11 is stopped and the hydraulic pump 10 is also stopped.

In the hydraulic elevator, the hydraulic pump 10 is driven except when the car descends in this way. Therefore, the hydraulic oil 9 discharged by the hydraulic pump 10 is compressed by the hydraulic pump 10 or the like. The oil temperature of 9 rises. Therefore, in order to prevent deterioration of the hydraulic oil 9 and the packing used in these hydraulic devices and maintain controllability of the acceleration / deceleration of the car, the hydraulic oil is cooled by the radiator 16 to approximately 45 ° C to 60 ° C. Used in the range of ° C. Therefore, the radiator 16
Is turned on / off by a signal from an oil temperature detector (not shown).

On the other hand, in the hydraulic elevator control device, the signal from the position detector provided in the car is compared with the position of the car set as a control pattern in advance, and the drive motor 11 and the hydraulic pump 10 are wound. The presence or absence of slippage of the mounted V-belt 12 is determined, and if the slippage of the V-belt 12 is recognized, means for stopping the car or stopping at the nearest floor is adopted.

[0015]

However, in the hydraulic drive system and the hydraulic elevator constructed as described above, when the car 4 is stopped at a predetermined floor and the bleed-off operation is performed, the Even if the belt 12 slips, it cannot be detected unless the position of the car 4 changes significantly, so the motor 11 continues to operate and the V-belt 12
Damage may develop.

Particularly, in a hydraulic elevator, the rotation frequency of the drive motor 11 including starting and stopping is high, and the temperature around the drive motor 11 is also high due to the hydraulic oil and the pump 10.
Further, if the hydraulic oil or the oil supplied to the rotary shafts of these machines scatters and adheres to the V-belt 12, the V-belt 12 may slip. Then, the objective of this invention is to obtain the hydraulic drive unit and hydraulic elevator which can detect the slippage of a belt easily and can prevent advance of an accident.

[0017]

According to another aspect of the present invention, there is provided a hydraulic drive system, a hydraulic pump having one side connected to an oil tank, an electric motor for driving the hydraulic pump via a belt, and a hydraulic pump. Side, which is connected via a flow rate adjusting valve, the load side of this hydraulic cylinder, the oil temperature in the oil tank, and the reference current of the electric motor set by the hydraulic pressure on the load side of the flow rate adjusting valve are input in advance. It is characterized in that it is provided with a slip detecting means for detecting the slip of the belt as compared with the current of (1).

The hydraulic elevator according to the second aspect of the invention is a hydraulic pump having one side connected to an oil tank, an electric motor for driving the hydraulic pump via a belt, and a flow rate adjusting valve on the other side of the hydraulic pump. A hydraulic cylinder that is connected through the elevator to raise and lower the car in the hoistway, and the load current of the car, the oil temperature in the oil tank, and the reference current of the motor set by the oil pressure on the load side of the flow rate adjustment valve are input in advance, and It is characterized by comprising a slip detecting means for detecting the slip of the belt as compared with the electric current.

Further, the hydraulic drive system and the hydraulic elevator according to a third aspect are characterized by further comprising electric motor stopping means for stopping the electric motor by the slip detecting means.

Further, in the hydraulic elevator according to a fourth aspect, a hydraulic pump having one side connected to an oil tank, an electric motor for driving the hydraulic pump via a belt, and a flow rate adjusting valve on the other side of the hydraulic pump. Connected to each other to raise and lower the car in the hoistway, the load current of the car, the oil temperature in the oil tank, and the reference current of the electric motor set by the hydraulic pressure on the load side of the flow rate adjusting valve are input in advance, and In comparison, it is characterized by including a slip detecting means for detecting a belt slip and a landing means for landing the car on the nearest floor on the lower floor side by the slip detecting means.

[0021]

According to the invention described in claims 1 and 2, the electric current of the electric motor reduced by the slip of the belt wound around the electric motor and the hydraulic pump is input to the slip detecting means and input to the electric motor in advance. The presence or absence of belt slip is detected by comparison with the reference value of the current.

In the invention according to claim 3,
The electric current of the electric motor, which is reduced due to the slip of the belt wound around the electric motor and the hydraulic pump, is input to the slip detecting means and compared with the reference value of the electric current input in advance to the electric motor to detect the presence or absence of the slip of the belt. At the same time, the electric motor is stopped by this detection signal.

Further, in the invention of claim 4, the electric current of the electric motor reduced by the slip of the belt wound around the electric motor and the hydraulic pump is input to the slip detecting means and is equal to that of the electric current previously input to the electric motor. The presence or absence of belt slip is detected by comparison with the reference value, and the detection signal causes the car to land on the nearest lower floor.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a hydraulic drive system and a hydraulic elevator according to the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing an example of a hydraulic drive system and a hydraulic elevator according to the present invention, and is a view corresponding to FIG. 5 shown in the related art. 2 is a connection diagram on the power source side of the drive motor 11 shown in FIG.

1 and 2, the difference from FIG. 5 shown in the prior art is that the power source side of the drive motor 11 is
A low-voltage three-phase AC electromagnetic contactor 19 is connected, and a penetrating current transformer 24 is provided on the power source side of the low-voltage three-phase AC electromagnetic contactor 19. Further, the step-down transformer 21 is connected to the current transformer 24.

The secondary side of this step-down transformer 21 is connected to the AD converter 22 of the control circuit 20 of the hydraulic elevator, and this AD
The digital signal output from the converter 22 is input to the microcomputer 23 of the control circuit 20. Further, a signal from an oil temperature detector (not shown) installed in the oil tank 7 and a detection signal from an oil pressure gauge (not shown) installed in the discharge pipe 14A are input to the microcomputer 23.

By the way, in the hydraulic drive system and the hydraulic elevator constructed as described above, the current value of the drive motor 11, that is, the torque, is proportional to the load of the hydraulic pump 10.
That is, it is proportional to the oil pressure inside the discharge pipe 14A. It also changes when the oil temperature changes, and decreases even if the V-belt 11 slips.

In the hydraulic system and hydraulic elevator of the present invention, information on the current value of the drive motor 11 input from the current transformer 24, the oil temperature signal input from the oil temperature detector of the oil tank 7 and the discharge pipe 14A. The hydraulic signal input from the hydraulic pressure gauge is input to the microcomputer 23, and compared with each preset set value to perform calculation to turn on / off the drive motor 11.

FIG. 3 shows the case where the load of the car is large,
6 is a graph showing the current value of the drive motor 11 when the V-belt 12 slips and the transition of this current value over time when the load on the car is small.

In FIG. 4, a curve I ₁ is a drive motor when the load of the car is large at a certain oil temperature and hydraulic pressure.
11 shows changes in current when the V-belt 12 slips at the initial stage of turning on 11. A curve I ₂ shows changes in current at the initial stage of the drive motor 11 when the load on the car is small and when the V-belt 12 slips at the above oil temperature and oil pressure.

In the hydraulic drive system and the hydraulic elevator according to the present invention, the reference values IN10 and IN20 of the electric current shown by the alternate long and short dash line in FIG. I ₁ , I shown in FIG.
₂ is the reference value IN10, IN20 at time t shown in FIG.
When it falls below, the drive motor 11 is stopped as judged that the V-belt 12 has slipped, as shown in step S2 of the flow chart of FIG.

If the stop position of the car 4 is located midway between the upper floor and the lower floor, step S2 in FIG.
As shown in step S4 of FIG. 3, while controlling the drive motor 11 as described above, the flow rate adjusting valve 15 is controlled to land the car on the nearest floor on the lower floor side to prevent the accident from spreading. prevent.

[0033]

As described above, according to the hydraulic drive system of the invention described in claim 1, a hydraulic pump having one side connected to an oil tank,
An electric motor that drives this hydraulic pump via a belt, a hydraulic cylinder connected to the other side of the hydraulic pump via a flow rate adjustment valve, the load temperature of this hydraulic cylinder and the oil temperature in the oil tank, and the load of the flow rate adjustment valve. The reference current of the electric motor set by the hydraulic pressure of the side is input in advance, and the slip detection means for detecting the slip of the belt is compared with the electric current of the electric motor, and the slip of the belt wound around the electric motor and the hydraulic pump is provided. By inputting the electric current of the motor reduced by the slip detection means and comparing it with the reference value of the electric current of the electric motor that was input in advance, the presence or absence of belt slip was detected. It is possible to obtain a hydraulic drive system that can prevent the occurrence of the problem.

Further, according to the hydraulic elevator of the invention described in claim 2, a hydraulic pump having one side connected to the oil tank,
An electric motor that drives this hydraulic pump via a belt, a hydraulic cylinder that is connected to the other side of the hydraulic pump via a flow rate adjustment valve to raise and lower the car in the hoistway, a load of the car and the oil temperature and flow rate in the oil tank. The reference current of the electric motor, which is set by the hydraulic pressure on the load side of the adjusting valve, is input in advance, and the slip detection means for detecting the slip of the belt is compared with the electric current of the electric motor. The electric current of the motor reduced by the belt slip is input to the slip detection means and compared with the reference value of the electric current of the motor input in advance to detect the presence or absence of the belt slip, so the belt slip can be easily detected. Then
It is possible to obtain a hydraulic elevator that can prevent an accident from occurring.

Further, according to the hydraulic elevator of the third aspect, by providing the electric motor stopping means for stopping the electric motor by the slip detecting means, the electric motor reduced by the slip of the belt wound around the electric motor and the hydraulic pump is provided. The current is input to the slip detection means and compared with the reference value of the electric current of the electric motor that has been input in advance to detect the presence or absence of belt slip, and the electric motor is stopped by this detection signal, so belt slip is easy. Detected in
It is possible to obtain a hydraulic elevator that can prevent an accident from occurring.

Further, according to the hydraulic elevator of claim 4, a hydraulic pump having one side connected to the oil tank, an electric motor for driving the hydraulic pump via a belt, and a flow rate adjusting valve on the other side of the hydraulic pump. A hydraulic cylinder that is connected through the elevator to raise and lower the car in the hoistway, and the load current of the car, the oil temperature in the oil tank, and the reference current of the motor set by the oil pressure on the load side of the flow rate adjustment valve are input in advance, and Compared with the electric current, the slip detection means for detecting the slip of the belt and the landing means for landing the car on the nearest lower floor side by the slip detection means are wound around the electric motor and the hydraulic pump. The presence or absence of belt slip is entered by inputting the electric current of the motor, which has been reduced by the belt slip, to the slip detection means and comparing it with the reference value of the electric current of the motor that was input in advance. And detects, by the detection signal, since the implantation of the cage to the nearest lower floor side, it is possible to slip the belt easily detected, to obtain a hydraulic elevator which can prevent occurrence of an accident.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view showing an embodiment of a hydraulic drive system and a hydraulic elevator according to the present invention.

FIG. 2 is a partial connection diagram showing an embodiment of a hydraulic drive system and a hydraulic elevator according to the present invention.

FIG. 3 is a graph showing the operation of the hydraulic drive system and the hydraulic elevator according to the present invention.

FIG. 4 is a flowchart showing the operation of the hydraulic elevator according to claims 2, 3 and 4;

FIG. 5 is a partial vertical cross-sectional view showing an example of a conventional hydraulic drive system and hydraulic elevator.

[Explanation of symbols]

1 ... Hoistway, 2 ... Guide rail, 3 ... Hydraulic cylinder, 4
... basket, 5 ... machine room, 6 ... frame, 7 ... oil tank, 8 ... filter, 9 ... hydraulic oil, 10 ... hydraulic pump, 11 ... electric motor, 12 ... V
Belt, 13 ... Suction pipe, 14, 14A ... Discharge pipe, 15 ... Flow control valve, 16 ... Radiator, 17 ... Building, 18 ... Landing doorway, 19 ... Low-voltage AC electromagnetic contactor, 20 ... Control device, 21 ... Transformer Bowl, 22 ... AD
Converter, 23 ... Microcomputer, 24 ... Current transformer.

Claims (4)

[Claims] 1. A hydraulic pump, one side of which is connected to an oil tank,
An electric motor for driving the hydraulic pump via a belt, a hydraulic cylinder connected to the other side of the hydraulic pump via a flow rate adjusting valve, an oil temperature on the load side of the hydraulic cylinder and in the oil tank, and the flow rate adjustment. A hydraulic drive device comprising: a reference current of the electric motor set in advance by a hydraulic pressure on the load side of the valve; and slip detection means for detecting slip of the belt by comparing with the electric current of the electric motor. 2. A hydraulic pump, one side of which is connected to an oil tank,
An electric motor that drives this hydraulic pump via a belt, a hydraulic cylinder that is connected to the other side of the hydraulic pump via a flow rate adjusting valve to raise and lower the car in the hoistway, a load of the car and oil in the oil tank. A hydraulic elevator comprising: a temperature and a reference current of the electric motor set by the hydraulic pressure on the load side of the flow rate control valve, and slip detection means for detecting a slip of the belt in comparison with the electric current of the electric motor. 3. An electric motor stopping means for stopping the electric motor by the slip detecting means is provided.
The hydraulic drive system according to claim 2 or the hydraulic elevator according to claim 2. 4. The hydraulic elevator according to claim 2, further comprising landing means for landing the car on the nearest floor on the lower floor side by the slip detection means.