JPH0289786A - Device for detecting abnormal lowering of oil viscosity of hydraulic elevator - Google Patents

Abstract

PURPOSE:To prevent the lowering of the operating speed of an elevator and the worsening in riding quality by providing an informing means for informing the lowering of oil viscosity at the time of judging that the oil viscosity is lowered below a defined value even though an oil temperature is in a defined temperature range. CONSTITUTION:Oil temperature is monitored by an oil temperature detecting means 16 while always monitoring oil viscosity by an oil viscosity detecting means 15. When the oil viscosity is abnormally lowered even though the oil temperature is within the range of ordinary values, the lowering of viscosity is informed to an operator by an informing means, to demand to change of oil 14 in an oil tank 10 and other operations. As a result, the lowering of the operating speed of an elevator and the worsening in riding quality can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an abnormal oil viscosity drop detection device for a hydraulic elevator.

(Prior Art) As hydraulic elevators, there are generally known two types of hydraulic elevators: a direct drive system in which a hydraulic jack is located directly below the car and directly raises and lowers the car, and an indirect drive system in which the car is raised and lowered through lobes and sheaves.

FIG. 7 schematically shows a direct drive type hydraulic elevator, in which a power unit 3 which is a drive source for the hydraulic elevator is provided in a machine room 2 adjacent to a hoistway 1.

The pressure oil generated by the power unit 3 is then transferred to the pipe 4
The car 7 above the plunger 6 moves up in the hoistway 1 when the plunger 6 moves up. Note that 8 is a guide device for moving the car 7 up and down along the guide rail 9.

On the other hand, regarding the descent of the car 7, pressure oil in the hydraulic jack 5 passes through the pipe 4 due to the weight of the car 7, and is returned to the tank 10 of the power unit 3, so that the car 7 is lowered.

Next, the structure and operation of this power unit 3 will be explained.

The power unit 3 includes a tank 10, an electric motor 11, a hydraulic pump 12, and a flow control valve 13. The hydraulic pump 12 driven by the electric motor 11 sucks oil in the tank 10, converts it into pressure oil, and discharges it. The flow control valve 13
The flow rate is controlled by and fed into the hydraulic jack 5. As a result, the plunger 6 of the hydraulic jack 5 rises, and the car 7 rises accordingly.

On the other hand, when descending, the pressure oil in the hydraulic jack 5 flows through the pipe 4 due to the weight of the car 7 and is returned to the oil tank lO, and by controlling the amount of return by the flow control valve 13, a predetermined traveling pattern is set. Car 7 is lowered accordingly.

(Problem to be solved by the invention) However, in such a conventional hydraulic elevator,
An oil viscosity abnormal decrease detection device for detecting a decrease in oil viscosity is not provided, and therefore there are the following problems.

Oil generally has the characteristic that its viscosity changes with changes in temperature, but in addition to this, oil deteriorates and changes in quality due to oxidation etc. while in use, and moisture in the air can also get mixed in. As a result, the viscosity tends to decrease abnormally and the moisture content tends to increase.

For this reason, the flow rate characteristics of the hydraulic pump 12 change greatly due to changes in viscosity, and as the viscosity decreases, internal leakage of the pump 12 increases, resulting in a decrease in the pump discharge amount and a problem in that the rising speed of the car 7 decreases. there were. In addition, when the viscosity of the oil decreases, the flow rate of the oil flowing through the control circuit (not shown) increases, and the movement of the valve body also increases accordingly. There was a problem in that the amount of oil flowing into the hydraulic jack 5 suddenly changes, resulting in poor riding comfort.

Furthermore, if moisture gets mixed into the oil and increases, rust will occur inside the hydraulic pump 12, increasing wear on the rotor (not shown), and rust will occur on various parts of the hydraulic jack, inside of the tank, etc. There were also some problems.

This invention was made in order to solve such conventional problems, and is a method for detecting an abnormal decrease in oil viscosity in a hydraulic elevator, which can detect and notify a decrease in viscosity before water contamination progresses too much. The purpose is to provide equipment.

[Structure of the Invention] (Means for Solving the Problems) The oil viscosity abnormal decrease detection device for a hydraulic elevator of the present invention includes an oil temperature detection means, an oil viscosity detection means, and an oil temperature detection means for detecting oil temperature. Comparing means for determining whether the detected temperature value is within a predetermined temperature range and the detected oil viscosity value from the oil viscosity detecting means with a predetermined comparison value, and determining whether the detected temperature value has decreased beyond this comparison value. An oil viscosity comparison means outputs a viscosity decrease signal when the oil temperature is within a predetermined temperature range, but the oil viscosity exceeds a predetermined value. and a notification means for notifying a decrease in oil viscosity when it is determined that the oil viscosity has decreased.

(Function) In the oil viscosity abnormal drop detection device for a hydraulic elevator of the present invention, the oil temperature is monitored by the oil temperature detection means, and the oil viscosity is constantly monitored by the oil viscosity detection means, so that the oil temperature is within the normal value range. However, if the oil viscosity has decreased abnormally, the operator can be prompted to change the oil or perform other operations by notifying the operator of the decrease in viscosity.

(Example) Hereinafter, embodiments of the present invention will be explained in detail based on the drawings.

FIG. 1 shows a portion of a power unit 3 according to an embodiment of the present invention. The construction of the hydraulic jack 5, plunger 6, car 7, etc. of the elevator hoistway 1 in this embodiment is the same as the construction shown in FIG. 7 for the conventional example. Further, in FIG. 1, the parts shown with the same reference numerals as in FIG. 7 have the same configuration.

In the power unit 3 shown in FIG. 1, the oil tank 10
Inside is a ura viscosity detector 15 for detecting the viscosity of ura 14.
and an oil temperature detector 16 for detecting temperature, these detectors 15 and 16 constitute a detection section of an oil viscosity abnormal decrease detection device 17.

Note that these detectors 15 and 16 detect the oil 14 in the tank 10.
is fed into the hydraulic jack 5 by the hydraulic pump 12, and is installed at a position where the oil viscosity and oil temperature can be detected even if the liquid level drops.

Further, as the oil viscosity detector 15, for example, a rotary type, vibration type, magnetic type, or ultrasonic type viscometer, which outputs a voltage as an output signal, is used. Similarly, oil temperature sensor 16
Also used are thermocouple, resistance, or thermistor thermometers that output voltage as an output signal.

FIG. 2 shows the circuit configuration of the oil viscosity abnormal drop detection device 17, which includes a comparator 19 that receives the output signal Vs1 of the oil viscosity detector 15 and compares it with the reference voltage Vr from the variable resistor 18, and this comparator A switching transistor 20 operated by the output of 19, this switching transistor 2
A relay coil 21 that is energized by 0 and a relay contact 21a that is closed when the relay coil 21 is energized are provided.

Further, the output signal V s 2 of the oil temperature detector 16 is inputted, and compared with the upper limit comparison value vh by the variable resistor 22, V
Upper limit comparator 2 that outputs when s H is less than vh
3. Compare with the lower limit comparison value Vl by the variable resistor 24, and
Lower limit comparator 2 that outputs when s1 exceeds Vl
5. AND gate 2 of the outputs of these comparators 23°25
6. A switching transistor 27 that is operated by the output of this AND gate 26, a relay coil 28 that is excited by this switching transistor 27, and a relay contact 28a that is closed by the excitation of this relay coil 28.
is provided.

29 and 30 are diodes, respectively.

The relay contact 21a and the relay contact 28a are connected to a power source P.
, N are connected in series, and a light emitting diode 31 for reporting an abnormal decrease in oil viscosity is further connected in series to these.

The operation of the abnormal oil viscosity drop detection device for a hydraulic elevator configured as described above will be described next.

As shown in FIG. 3, the oil viscosity detector 15 exhibits a characteristic that the larger the oil viscosity, the larger the voltage signal vsI output, and the lower the viscosity, the lower the output voltage V s 1 .

Moreover, the oil temperature detector 16 is 1. As shown in FIG. 4, the higher the oil temperature, the higher the output voltage V s 2 is output.

Therefore, the oil viscosity detector 15 and oil temperature detector 16 provided in the oil tank 10 are operated according to the viscosity and temperature, respectively, as shown in FIG.
The output voltage signal V s IV s 2 shown in FIG.
Give the human power part of the circuit shown in the figure.

For example, when the oil temperature gradually rises when the elevator starts operating, the output voltage of the oil temperature detector 16 also gradually rises as shown in FIG. gradually decreases, and the output voltage of the oil viscosity detector 15 gradually decreases as shown in FIG.

Here, when the input Vs2 of the comparators 23 and 25 reaches between the lower limit voltage Vl and the upper limit voltage vh due to the rise in oil temperature, both comparators 23 and 25 output, and AN
D gate 26 opens and switching transistor 27 is turned on, energizing relay coil 28 and closing relay contact 28a.

Also, due to the decrease in oil viscosity due to the increase in oil temperature, comparator 1
When the human power V s 1 of 9 decreases and falls below the reference voltage Vr, the comparator 19 outputs an output, turns on the switching transistor 20, excites the relay coil 21, and closes the relay contact 21a. Note that this reference voltage V is set to be, for example, about 30% lower than the voltage value corresponding to the viscosity shown by the decrease in viscosity due to a normal temperature rise, and is designed to respond to an abnormal decrease in oil viscosity. It is set to .

In this way, if the oil temperature rises to a predetermined range and the oil viscosity in this state is abnormally lower than normal viscosity, the relay contact 21a.

28a are turned on at the same time, and the light emitting diode 31 connected in series to these emits light to notify abnormal decrease in oil viscosity.

In this way, in this example, the viscosity of the oil decreases as its temperature increases, but in order to detect moisture contamination and deterioration as factors that lower the viscosity regardless of temperature, the oil temperature is maintained within a certain range. If a viscosity that is abnormally lower than the oil viscosity considered in that temperature range is detected when the temperature is within the temperature range, it is determined that the oil viscosity has decreased abnormally, and the viscosity decrease is notified.

It should be noted that the present invention is not limited to the above-described embodiments; for example, as shown in FIG. 5, a buzzer 32 may be provided together with a light emitting diode 31 as a means for notifying an abnormal decrease in oil viscosity.

Also, as shown in FIG. 6, a relay contact 21a.

If a relay coil 33 is provided in series in the series circuit of 28a, a self-holding relay contact 33a is provided in parallel to the relay contacts 21a and 28a, and a light emitting diode 31 and a resistor 34 are connected in series to this. Once it is detected that the oil temperature is within a certain range and the oil viscosity has decreased abnormally, the relay contacts 21a and 28a are closed, and the relay coil 33 is energized. The holding relay contact 33a closes to self-hold the relay coil 33, allowing the light emitting diode 31 to continue operating, and even if maintenance personnel are not present when an abnormal drop in oil viscosity is detected, the light emitting diode 31 can be activated later. It is possible to confirm the occurrence of an abnormality when the number 31 is emitted.

Further, the installation location and number of the oil viscosity and oil temperature detectors are not limited to one, but may be installed at a plurality of locations for detection.

Furthermore, it can be connected to an elevator control device so that when an abnormal decrease in oil viscosity is detected, the elevator can be operated to the nearest floor and then stopped.

[Effect of the invention 1 As described above, according to the present invention, if the oil viscosity abnormally decreases beyond the standard value even though the oil temperature is within the normal range, an abnormal decrease in oil viscosity is notified. Therefore, by replacing or purifying the oil when an abnormal drop in oil viscosity is notified, elevator operating speed may be reduced and ride comfort may be worsened because abnormal drops in oil viscosity are not monitored as in the past. You will never know about an abnormal drop in oil viscosity until it happens, and you can prevent a drop in elevator operating speed and deterioration of ride comfort.

[Brief explanation of the drawing]

FIG. 1 is a mechanical configuration diagram showing the power unit portion of an embodiment of the present invention, FIG. 2 is a circuit diagram of the above embodiment, and FIG.
The figure is a characteristic diagram of the oil viscosity detector in the above embodiment, Figure 4 is a characteristic diagram of the oil temperature detector in the above embodiment, Figure 5 is a circuit diagram of another embodiment of the present invention, and Figure 6 is a characteristic diagram of the oil temperature detector in the above embodiment. A circuit diagram of still another embodiment of the invention, FIG. 7 is a mechanical configuration diagram of a general hydraulic elevator. 3...Power unit 10...Oil tank 12...
・Hydraulic pump 14... Oil 15... Oil viscosity detector 16... Oil temperature detector 17... Oil viscosity abnormality drop detection device 18... Variable resistor 19... Comparator 20...
・Switching transistor 21...Relay coil 21a...Relay contact 2
2... Variable resistor 23... Upper limit comparator 24.
... Variable resistor 25 ... Lower limit comparator 26 ...
AND gate 27... switching transistor

Claims (1)

[Claims] an oil temperature detection means, an oil viscosity detection means, a judgment means for determining whether an oil temperature detection value from the oil temperature detection means is within a predetermined temperature range, and oil viscosity detection from the oil viscosity detection means. an oil viscosity comparison means that compares the value with a predetermined comparison value and outputs a viscosity reduction signal if the value has decreased beyond the comparison value; and an output from the oil temperature judgment means and the oil viscosity comparison means. an oil viscosity reduction alarm for a hydraulic elevator, the oil viscosity of which is lowered is determined to be lower than a predetermined value even though the oil temperature is within a predetermined temperature range based on the output of the hydraulic elevator. Abnormal viscosity drop detection device.