JPH08301546A - Hydraulic elevator - Google Patents

Abstract

PURPOSE: To prevent a seize of a motor by immediately emergency-stopping an elevator at the time of raising of a cage and descending it to the lower nearest floor, descending it to a target floor as such at the time of descending of the cage and further descending it to the lowermost floor and stopping a traveling in the case where a low level of an operation fluid is detected. CONSTITUTION: When a low oil switch 18 detects a low level, a control board 15 outputs a signal to a motor 5 and emergency-stops a cage 1 based on a signal from a rotary encoder 16 at the time of not landing but raising of the cage 1. Next, a present position is confirmed, a signal is outputted to a descending valve 14 and the descending valve 14 is opened to descend the cage 1 to the lower nearest floor. In the case where the nearest floor is not the lowermost floor, the cage 1 is descended to the lowermost floor and a traveling is stopped. The cage 1 is descended to a lower target floor as such at the time of descending and a zone sensor 17 detects whether or not the cage 1 arrives at the target floor. Next, the cage 1 is descended to the lowermost floor and a traveling is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic elevator that raises and lowers a car by using hydraulic pressure.

[0002]

2. Description of the Related Art In a conventional hydraulic elevator, a motor drives a pump to pump hydraulic oil in a tank to a cylinder of a hydraulic jack, push up a plunger to raise a car, and hydraulic oil in a cylinder to a tank. The car is lowered by discharging it.

[0003]

By the way, in order to pump the hydraulic oil from the tank to the cylinder, the tank and the cylinder are connected by piping, but the piping may be damaged or the hydraulic oil may leak. It may happen. This will reduce the amount of hydraulic oil in the tank.

Here, in order to raise the car, hydraulic oil in the tank is pumped up by a pump. For this reason,
When the amount of hydraulic oil in the tank is less than the minimum required low level, air will be mixed in when pumping this hydraulic oil. If hydraulic oil containing air is pumped to the cylinder, the motor will burn and cannot be reused.

It is an object of the present invention to provide a hydraulic elevator in which the operation of the motor is stopped when the motor may be burned so that the motor can be reused.

[0006]

In order to achieve such an object, according to the present invention, a hydraulic jack for ascending and descending a car disposed in a hoistway and a car, and hydraulic oil are stored. Tank, a pump for pumping hydraulic oil from the tank to the hydraulic jack through piping, a motor for driving the pump, and the hydraulic oil in the hydraulic jack installed in the piping to the tank. A control valve for discharging, a control means for controlling the control valve and the motor, and a low oil switch for detecting whether or not the operating oil in the tank is at a necessary minimum low level are provided. If the switch detects that the hydraulic oil is below the low level, immediately stop the emergency when the car is rising and then lower it to the nearest floor below, or As it is lowered into the destination floor when the Funaka, then the has a configuration which is adapted to suspend operation after further lowered to the lowest floor of the car from the nearest floor or the destination floor.

[0007]

[Operation] When the low oil switch detects that the hydraulic oil is at a low level or lower, immediately stops the emergency when the car is rising and then lowers it to the nearest floor below, or when the car is descending. At times, the car is lowered to the destination floor as it is, and then the car is further lowered from the nearest floor or the destination floor to the lowest floor, and then the operation is suspended.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. 1 and 2 are views showing an embodiment of a hydraulic elevator according to the present invention.

In FIG. 1, reference numeral 1 is a car disposed in the hoistway, and the car 1 is raised and lowered by a hydraulic jack 2. The hydraulic jack 2 is composed of a cylinder 3 and a plunger 4. When hydraulic oil is pumped into the cylinder 3, the hydraulic jack 2 pushes up the plunger 4 to raise the car 1 provided in the plunger 4, while discharging the hydraulic oil in the cylinder 3. Then, the car 1 descends.

The hydraulic oil pumped to the cylinder 3 drives the pump 6 by the motor 5 and is pumped from the tank 7 through the pipe 9. At this time, the check valve 10 is provided in the middle of the pipe 9, and the working oil is pressure-fed to the cylinder 3 through the check valve 10. However, the pressure of the working oil becomes too large and the predetermined pressure is exceeded. If it exceeds, there is a possibility that the cylinder 3 may be damaged, so a part is returned to the tank 7.

Pipings 11 and 12 for returning the hydraulic oil to the tank 7 are connected to both sides of the check valve 10 in the piping 9, and the ascending valve 1 including a solenoid valve is connected to the pipings 11 and 12.
3. A down valve 14 (control valve) is provided. Ascent valve 1
3 is for returning the hydraulic oil to the tank 7 when the hydraulic oil exceeds a predetermined pressure, and the descending valve 14 is for returning the hydraulic oil in the cylinder 3 to the tank 7.

The drive of the motor 5 is controlled by a control board 15 (control means) installed in the machine room.
5 also controls the ascending valve 13 and the descending valve 14. The control panel 15 receives a signal from a rotary encoder 16 (position detecting means) for detecting the position and traveling direction of the car 1, and a zone sensor 17 for detecting that the car 1 has landed. Input the signal from.

A signal from the low oil switch 18 is also input to the control panel 15. The low oil switch 18 is composed of a float floated on the working oil in the tank 7, a potentiometer for detecting the up and down of the float, and the like. The low oil switch 18 is for checking whether or not the working oil in the tank 7 is at a required minimum low level or more, and when it becomes below the low level, the low oil switch 18 detects it and outputs the detection signal. Is output to the control panel 15.

Here, the low level means a level (minimum necessary) where air is not mixed into the hydraulic oil when the hydraulic oil is pumped up from the tank 1. Also,
The low level is a level when pumping up the hydraulic oil, and therefore is relevant only when the car 1 is rising, and is not relevant when the car 1 is descending.

Next, the operation of this hydraulic elevator will be described with reference to the flow chart shown in FIG.

When the low oil switch 18 detects a low level, this signal is output to the control panel 15 (step S ₁ ). The control panel 15 determines whether the car 1 is currently landing on the floor based on the signal from the rotary encoder 16 (step S ₂ ).

When the car 1 is not landing, it is determined whether the car 1 is rising (step S ₃ ). When the car 1 is rising, the control panel 15 drives the motor 5
A signal is output to stop the pump 6 and stop the car 1 in an emergency (step S ₄ ). Then, check the current position of the rotary encoder 16 Dekago 1 (step S _5). Next, a signal is output from the control panel 15 to the descending valve 14, and when the descending valve 14 is opened, the hydraulic oil is discharged from the cylinder 3 and the car 1 descends to the nearest floor below (step S ₆ ). Next, the zone sensor 17 detects whether or not the car 1 has arrived at the nearest floor (step S ₇ ).

When the car 1 arrives at the nearest floor, the door is opened based on the signal from the control panel 15 and the door is left open for a predetermined time (step S ₈ ). During this time passengers are in the basket 1
Get out of Next, it is determined based on whether the nearest floor is the lowest floor to the signal from the rotary encoder 16 (step S _9).

Next, when the nearest floor is not the lowest floor, the descending valve 14 is opened again and the car 1 is lowered to the lowest floor (step S ₁₀ ). The zone sensor 17 detects whether or not the car 1 has arrived at the bottom floor (step S ₁₁ ). Upon arrival from the car 1 to the lowest floor, and the service in the dormant state (step S _12). That is, the door is left open so that it does not light up even if the hall button or the car button is pressed. On the other hand, when it is determined that the nearest floor is the lowest floor based on the signal from the rotary encoder 16, the operation is stopped immediately.

Here, even while the operation is stopped, the hydraulic oil leaks more and more, and in some cases, falls from the bottom floor. However, a shock absorber for soft landing when the car 1 falls is provided on the bottom of the hoistway below the lowest floor, so that the car 1 is prevented from falling greatly. .

When the car 1 is not rising but is descending, the car 1 is descended to the lower destination floor as it is (step S ₁₃ ).
Then, the car 1 is detected by the zone sensor 17 whether arrived destination floor (step S _14). When the car 1 arrives at the destination floor, it opened the door as described above, then moved down to the lowest floor, then halting the operation (step S ₈ ~
S ₁₂ ).

[0022] After the low oil switch 18 detects a low level, when the car 1 is in landing, the actuating likewise just as open the door (S ₈ ~S _12).

As described above, when the car 1 is located at the lowest floor and the operation is stopped, the motor 5 is prevented from seizing.

[0024]

As described above, according to the present invention,
If the low oil switch detects that the hydraulic oil is below the low level, immediately stop the emergency when the car is rising and then descend to the nearest floor below, or when the car is descending, continue to the target floor. Since the car is further lowered to the lowest floor from the nearest floor or the destination floor, the motor is not burned. Further, if the location where the hydraulic oil leaks is repaired while the operation is stopped and then the hydraulic oil is supplied to the tank, the motor can be reused.

On the other hand, since the operation of the car is stopped after the car is lowered to the lowest floor, the car is prevented from falling largely.

[Brief description of drawings]

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

FIG. 2 is a flowchart showing the operation of this elevator.

[Explanation of symbols]

 1 ... Basket 2 ... Hydraulic jack 5 ... Motor 6 ... Pump 7 ... Tank 14 ... Down valve 15 ... Control panel 16 ... Rotary encoder 18 ... Low oil switch.

Front page continued (72) Inventor Katsumi Maeda 3-2-1 Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa Nihon Otis Elevator Co., Ltd.

Claims (1)

[Claims] 1. A car provided in a hoistway, a hydraulic jack that raises and lowers the car, a tank that stores hydraulic oil, and a hydraulic oil that is pumped from the tank to the hydraulic jack through a pipe. A pump, a motor that drives the pump, a control valve that is interposed in the pipe, and that discharges the hydraulic oil in the hydraulic jack to the tank, and a control unit that controls the control valve and the motor. A low oil switch for detecting whether the hydraulic oil in the tank is at a minimum necessary low level, and if the low oil switch detects that the hydraulic oil is below the low level, the car rises When the car is in the middle, immediately stop the emergency and then descend to the nearest floor below, or when the car is descending, descend to the destination floor as it is, and then the nearest floor or A hydraulic elevator characterized in that the car is further lowered from the physical floor to the lowest floor and then the operation is suspended.