JPS63282063A - Detector for temperature of oil for hydraulic elevator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field]

This invention relates to an improvement in an oil temperature detection device for a hydraulic elevator.

[Conventional technology]

FIG. 9 is a block diagram showing a conventional oil temperature detection device for a hydraulic elevator, as disclosed in, for example, Japanese Patent Laid-Open No. 57-170372. In the figure, 1 is the cylinder filled with oil 2, 3 is the cylinder 1
4 is a cage coupled to the head of the plunger 30; 5 is a conduit connected to the cylinder 1; 6 is a plunger inserted therein;
is connected to the pipe line 5, and when activated sends pressure oil to the pipe line 5, a rising solenoid valve; 7 is a descending solenoid valve that also discharges oil from the pipe line 5; 8 is connected to a rising solenoid valve 6. 9 is a hydraulic pump electric motor that drives the hydraulic pump 8, 10 is an oil tank connected to the lowering solenoid valve 7 and the hydraulic pump 8, and 90.91 is an oil temperature installed in the oil tank 10. It is a detector. That is, when a lift command is issued, the electric motor 9 rotates, drives the hydraulic pump 8, and controls the lift solenoid valve 6. Now, the tank 100 oil 2 is sent from the lifting solenoid valve 6 to the cylinder 1 through the pipe line 5, so the car 4 moves up. Further, when a descending command is issued, the descending electromagnetic valve 7 is controlled, and the oil 2 in the cylinder 1 is discharged to the oil tank 10 through the pipe 5 and the electromagnetic valve 7, so that the car 4 descends. In a hydraulic elevator, when the temperature of the oil 2 decreases, the viscosity of the oil 2 changes, and the ride comfort of the car 4 deteriorates, and the landing error increases. Therefore, regulations also stipulate that the oil temperature must be kept above a certain value. The oil temperature detectors 90 and 91 detect this, and when the oil temperature falls outside the lower limit, the oil temperature detector 90 is activated, causing the motor 9 to idle and not sending oil pressure into the cylinder 1. 2 to oil tank 10
The oil 2 is heated and the oil temperature is raised by circulating the oil 2 through a suitable pipe line (not shown). This operation continues for a certain period of time and then is stopped. Next, when the oil temperature rises and exceeds the upper limit, the oil temperature detector 91 is activated, the calling circuit is disconnected, and the operation of the car 4 is stopped, thereby cooling the oil 2 and lowering the oil temperature. let In this way, the oil temperature is maintained between the upper and lower limits.

[Problems to be solved by the invention]

In conventional oil temperature detection methods, the oil temperature detector can only detect either rising or falling oil temperature fluctuations, so two oil temperature detectors are provided to constantly detect both rising and falling fluctuations. It is necessary to separately detect rising fluctuations and falling fluctuations with each oil temperature detector, and therefore two oil temperature detecting devices must be provided, making the entire device larger and more expensive. This invention solves the above problems and makes it possible to detect all oil temperatures within the oil temperature range used in hydraulic elevators using a single oil temperature detector. However, since detection and car control are required, the purpose is to load the corresponding circuit. Means for Solving the Problems] The oil temperature detection device for a hydraulic elevator according to the present invention calculates in advance the upper part of each sensor output voltage with respect to the oil temperature detected by the oil temperature detection sensor, and stores it for each address. It has a memory section that
The output voltage information is inputted in a predetermined voltage level order to the comparator to which the temperature sensor output is input, and the presence or absence of a change in the output logic level output from the comparator is detected, and the presence or absence of a change in the logic level is detected. At the time of detection, it is determined whether there is an abnormal fluctuation in the oil temperature or whether the oil temperature sensor is defective, and when the abnormality is determined, the oil temperature data value at that time is held.

[For use]

In a state where the comparator of the oil temperature detection device for a hydraulic elevator in this invention is inputting a constant level of oil temperature detection voltage from the oil temperature sensor, the oil temperature sensor outputs an output from the storage unit via the D/A converter. Voltage output signals from the maximum possible voltage level to the minimum voltage level are sequentially inputted by the scanning means in a predetermined procedure, and when the logic output level of the comparator is scanned, if an abnormal oil temperature is detected, the oil temperature is The temperature data is stored and retained, and the car is controlled in a predetermined manner.

【Example】

An embodiment of the present invention will be described below with reference to FIGS. 1 to 8. In addition, in FIG. 3, 1 to 10 indicate the same parts as in FIG. 9. FIG. 1 is an overall configuration diagram of an embodiment of an oil temperature detection device for a hydraulic elevator according to the present invention. As is clear from FIG. 1, an oil temperature sensor 11 is provided to detect the temperature of the oil 2 in the oil tank 100, and the temperature detected by the oil temperature sensor 11 is converted into a voltage to make the comparator 15 manually operated. , the input value is compared with the preset voltage value for each oil temperature detected by the oil temperature sensor, from the maximum voltage level to the trouble voltage level, and the logic output level of the comparator 15 is determined by the scanning means 1.
As a result of scanning by a and detecting whether or not there is a reversal of the logical output level during scanning, the level detecting means 1b determines the oil temperature based on the set voltage level at the time of the logical output level reversing, and when no level reversal is detected, the abnormality determining means The IC determines abnormal fluctuations in oil temperature or failure of the oil temperature sensor. Then, based on the determination result, the oil temperature control circuit 26 is driven to safely operate the hydraulic elevator. In FIG. 2, 11 is an oil temperature sensor, for example, an NTC thermistor or the like is used. (+) is a DC power supply, 12 to 14.
17 is a resistor, 18 is a variable resistor, 15 is a comparator, 16 is D
/A converter, Vs is this reference voltage input, DI is D0 ~
8-bit digital signal input consisting of D7, VD
is the analog output voltage determined by Dl and ■3. 20 is a microcomputer having scanning means, level detection means, and abnormality determination means; 21.25 is an interface input and output circuit for converting analog signals and digital signals, and receives signals from the CPU 22; 23
is a ROM, and 24 is a RAM. 26 is an oil temperature control circuit in the circuit, and 27 is an oil temperature raising circuit when the oil temperature drops, □, for example, rotates the electric motor to recirculate the oil, or connects a heater. In addition, the oil temperature control circuit 2
6, 28 is an operation stop circuit when the oil temperature rises, and for example, disables the hall call and stops the car as being unable to start. 3
0 is an abnormal oil temperature control circuit, which performs, for example, a pause operation or a thinned-out operation (extension of door opening time) depending on the situation. FIG. 4 is a temperature-voltage characteristic diagram showing the relationship between the temperature detected by the thermistor 11 and the output voltage. -Finally, hydraulic elevators normally operate within the range of 5℃ to 60''C, so the temperature can generally be controlled within this range, but errors in detection circuits such as thermistors and low temperatures may occur during winter installation. Considering the case where the oil temperature is low, the oil temperature detection range should be controlled within the range of -5°C to 70°C.Since the oil temperature detection range has been set as above, it can be divided by resistance R1 and thermistor resistance RTH. The voltage VT)l appearing across the thermistor 11 is equal to the thermistor partial voltage (V
The reason why TH (-5)) is larger than the thermistor partial voltage (VTE, (70)) when the detected oil temperature is 70°C is because the NTC thermistor is used. Next, the setting of the analog output of the D/A converter 16 will be explained. If the oil temperature is lower than -5'C above, or thermistor 1
1 is disconnected, it is necessary to determine that this is abnormal when detecting the oil temperature, and it is necessary to make it impossible to start the operation outside the oil temperature control based on this abnormality determination. Therefore, in order to achieve this, when D, input D0 to D, and all bits are set to "1", the analog output VD is set to a temperature lower than the above VTM (-5) (for example, VTH (-5) + 0.3V). Change the value of resistor 18 so that VS is set. Next, the oil temperature detection operation will be explained with reference to FIGS. 5 to 8. In FIG. 5, 23 is a ROM, for example an EPROM or an EEP.
Consists of ROM. Here, the VT is the voltage converted from the resistance change value according to the thermistor oil temperature calculated in advance.
The digital input voltage information D1 for outputting the H(!-same voltage/A conversion output VD) is stored as an 8-bit binary value consisting of bits D0 to D, and is stored at address 1.
After address 000, for example, T M (-5) to T M
(70) Mateno values (76 values) are stored in 1°C increments. Therefore, as mentioned above, TM(-5)=FF)1 (-5
The reason is that it contains the value at °C. 6 to 8 are oil temperature detection programs, and the initial setting routine in FIG. 6 is a program that is executed only when the power is turned on or when the CPU is reset, for example. When the power is turned on now, the CPU 22 will go through this initialization routine after being reset. As a result, in flow 5o, 0UT1. In other words, D0 to D, FF whose 08 bit signals are all “1”
, I, which is input to D/A converter 1
6 output■. generates a voltage of VtM(-5) + 0.3V. At the same time, this output value is stored in THMO on RAM24.
is stored as. After this, depending on the interrupt cycle setting in flow 51 (for example, according to Intel 8085A, RST7.5
After a certain period of time (in order to set periodic interrupts such as If all the oil temperature sensors 11 are disconnected, the oil temperature sensor 11 will be at the oil temperature of 1, and the comparator 15
The (+) input oil temperature sensor voltage Yell is Vta(-
5). Therefore, since this value is larger than the (-) inputs of the comparator 15, the comparator 15 outputs a (+) potential, and the input circuit 21 inputs the 'FFMJ signal to the CPU 22 with the (+) voltage. For this reason, according to flow 52 in FIG.
-FF is stored in the RAM 24. Next, as a result of determining that VTM is larger than VTM (-5) in flow 53, by passing through flow 56.57, F L
A G = F F H, and THCG and THMO
Input the value FF. As a result, the current oil temperature is set to FF as a data value. This means that it has been recognized that it has become. Next, in flow 58, THMO is set to the value of (FF, -1) 'FE HJ, and in flow 59.60, it is again set to D0 to D, and the value is D.
+ and output through a D/A converter. This output voltage is D + = FF M, which is the output voltage. Next, when another interrupt occurs, the process starts again from flow 52, and in this case too, the oil temperature sensor voltage vTH is VT)I(
-5), so THMI=FF, and FL
AGI-FF, so it will go from 56 to 61. As a result, the oil temperature value is determined to be FF. From now on, T.H.
Repeatedly execute the process of subtracting 1 from MO, and at 61, “Y
”, and as it passes through 64, it is determined that the oil temperature is out of the normal oil temperature range, so it passes through flow 55, and at 63, the output and flag are reset. When it is determined that the oil temperature is outside the range, in this example, in flow 55, an output is issued to turn off the oil temperature indicator 29, an abnormal signal is generated, and the abnormal oil temperature memory T is
Since the data of the detected oil temperature THCG is input to the HCG, the oil temperature control circuit 26 maintains the abnormality control operation 29, and causes the elevator to be stopped, rendered inoperable, etc., for example. As described above, after an abnormality in the oil temperature detection section of the elevator is determined by turning off the oil temperature indicator, when an interruption occurs again, the process of flow 52 is performed again. The detection circuit that replaces the oil temperature sensor and the like is composed of a semiconductor such as a thermistor, but when the thermistor is used with a large current or voltage, the resistance change increases due to self-heating of the thermistor, resulting in a detection error. For this reason, it must be driven at low voltage. However, if such a low-voltage, low-current thermistor detection signal is sent from the oil tank to the control panel, there is a risk of a surge occurring between the two, and in this case, even though the oil temperature is normal, the oil temperature sensor 1
When the signal to the comparator 15 of No. 1 is input to the microcomputer 20, it may be input as an abnormal oil temperature as described above. In this program, since the oil temperature is not determined to be abnormal due to the accidental mixing of abnormal signals as described above, the same oil temperature determination process is always performed at a constant cycle when the CPU is operating. As a result, if the voltage input according to the oil temperature is input without making the above abnormality determination, THMI will not go to flow 54 for the first time, so it will go to the processing from flow 53 onwards, and when the predetermined oil temperature is determined, the flow will flow. 54 is released and normal display and operation are performed. Next, a case where the oil temperature is 6°C, for example, will be explained. T
It is assumed that the HMO is set to the maximum value through flow 50 or flow 63. ■The voltage of VTM (6) is generated in the eye, and the (-) side D/A output of the comparator 15 (VyH (-5
) + 0.3V) is larger, so in this case flow 5
In 2.53 THMI is 'OOMJ and also FLAG
Since I has been reset, flow 58 is passed from flow 54. As a result, the full open output value THMO is subtracted by 01.1,
Voltage information is output to the D/A converter 16. Since the output is output from the D/A converter 16, the comparator 15 compares the oil temperature sensor output with the analog voltage value and outputs a logical output. After this, side interference is applied and the TH
The MI signal is captured, but with a difference of about 018, VD
The output decreases only slightly, and the same operation is repeated. T.H.
When MO is sequentially subtracted and reaches the value of oil temperature 6°C (TH(6) or TH(6)-01,'), the voltage on the input (-) side of comparator 15 becomes large, so an interrupt occurs. flow 52
When THM 1 comes to , it changes from "00H" to 'FFMJ, passes through flows 53 and 56, and reaches flow 57. The oil temperature data THMO corresponding to the fully output oil temperature value is stored in THCG by flow 57, and this oil temperature detection device detects the oil temperature in the oil tank by capturing the change in THMI. At the same time, after putting 'FFMJ in FLAGI and subtracting THMO four times again, the interrupt is set to ``FROM 53-53-56-61''.
Y”, that is, from THMI'0OIIJ to rF
The oil temperature data at the point where the change to FNJ was captured is memorized, and then the oil temperature data is lowered and output, so if it is normal, THMI will always be rFF, J, indicating that it has been normal four times. After making a determination, the process proceeds to the next subroutine 62. This is because when the difference between the output voltage of the thermistor oil temperature sensor and the D/A output voltage is almost O■, the comparator 15 outputs a forward and reverse voltage if either is even slightly high. Area removal and oil temperature change from moment to moment, and in some cases, the comparator 15 may oscillate and repeat positive and reverse voltages. THMI is “00”,
Either rFFJ can occur, and THMI has unreliable data that says "Even though it has become FFHJ,
Next, input '0ONJ' to go through the flow 53-54-63 and start again from the beginning (THMO is from 'FFIIJ)
Reliability is increased by performing calculations. On the other hand, if the THMI value continues to be ``FFHJ'' four times from the time of the change, the process goes to flow 62, determines that the oil temperature detection is reliable, and executes the oil temperature determination subroutine process. The oil temperature determination routine is shown. All detected oil temperature data is stored in the memory as THCG. On the other hand, the second
The figure ROM 23 contains the set oil temperature data value corresponding to the oil temperature value as described above, and in the flow 71, the 7 row 77
The loop of returning to 71 is repeated, and the set oil temperature data value is moved to the high temperature side, and the set oil temperature data value T M
When (7) becomes 7°C, proceed to 73 using the detective in flow 71, and in 76 FLAG2 is set to rFF in advance.
, J, the program goes to the subroutine 74 and outputs the oil temperature, for example "6", from the output circuit 25 to the display 29. As a result, the oil temperature detection is completed, and the oil temperature detection is repeated again in the same manner through the flow 75-63. in this case,
The oil temperature is low, for example, the lower oil temperature set in advance.

(for example, 10° C.), a signal is output to the oil temperature raising circuit 27 through the output circuit 25, and an oil temperature raising operation is performed. Even when the soil temperature is within the normal range and on the high temperature side, similar oil temperature detection is performed and the oil temperature is displayed, and a signal is input to the operation stop circuit 28 to prevent the oil temperature from rising by stopping the operation or the like. In this case, the return to operation is also performed by similar oil temperature detection and settings in the operation processing subroutine. Next, a case will be described in which, for example, the oil temperature sensor becomes short-circuited. In this case, VTH is 0■, and the (+) side of the comparator 15 is 0■. As before, THMO is subtracted from rFF and J, but since the (-) side of comparator 15 is high voltage, THM 1 is '0011J, and 52-53-54-58-59-61 in Figure 7 Each loop is sequentially repeated (.Here, when the THMOO value becomes '2F>IJ (for example, a value of 70°C) in this example, the flow 59
4-5, the oil temperature display is turned off as in the case of disconnection, and when an abnormal signal is generated, for example, the elevator is stopped. Here, the final value of THMO output is 2F, and the final value is 001.
When subtracted to 1 and compared, it is possible that the output of the D/A converter 16 may be less than 0 due to variations in elements, aging, etc. Also, depending on a failure of the operation stop circuit 28, the oil temperature may be normal. Since it is conceivable that the oil temperature may rise beyond the range, the structure is designed to minimize this including the oil temperature detection error. If the above-mentioned disconnection or short circuit occurs temporarily (for example, a disconnection due to poor contact or a short circuit due to contact with a conductor) and the abnormal condition is restored, the oil temperature detection circuit Therefore, during this oil temperature detection operation, the normal oil temperature is detected and a normal display is displayed, and there is a risk that the abnormality may be overlooked.For this reason, as mentioned above, when an abnormal oil temperature is recognized, this oil temperature Since the data is stored and retained as THCGM, it is possible to clarify the cause of the abnormal operation of the car, and it is also easy to detect temporary defects. When the customer cut off the power,
Even in cases where the user thinks that the problem will be resolved by turning the power on again, it can be maintained by adding a known memory backup circuit (for example, a circuit that is maintained by a battery or the like - not shown). In addition, instead of using an A/D converter, we used a D/A converter to detect one count of oil temperature every interrupt cycle. This is because the response of the thermistor oil temperature sensor is slow because it is not directly immersed in oil, so it can be used without any problems in actual use. Further, although the set oil temperature data is set in units of 1'C, there is no particular restriction. Further, although the display in the event of an abnormality is turned off, it is also possible to have a display other than numbers and to distinguish between a disconnection or oil temperature drop abnormality and a short circuit or oil temperature rise abnormality by lighting them up. As described above, according to the present invention, the voltage output value of the oil temperature detection sensor and the sensor for each oil temperature, which is wider than the normal oil temperature range in which the sensor detects the oil temperature, can be adjusted. The output voltage setting value is compared with a comparator over the entire oil temperature range, and the oil temperature is detected based on the logic output level reversal detection of the comparator during the comparison, and if an abnormality in oil temperature is detected, this is memorized. At the same time, the oil temperature control circuit is activated in the event of an abnormality, so
Abnormalities in the oil temperature detection circuit can be detected early, and since the oil temperature data at this time is stored and retained, the cause of the abnormality can be discovered early.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of an oil temperature detection device for a hydraulic elevator according to the present invention, FIG. 2 is a configuration diagram showing the electrical connections of an oil temperature detection circuit according to the invention, and FIG. 3 is a configuration diagram of a hydraulic elevator. Figure 4 is a characteristic diagram of the oil temperature detector, Figure 5 (a)
, (b) is a memory configuration diagram of the storage section, FIGS. 6 to 8 are flowcharts showing the oil temperature detector program, and FIG. 9 is a configuration diagram of a conventional hydraulic elevator. 1a...Scanning means, lb...Level detection means, IC
... Abnormality determination means, 2... Oil, 10... Oil tank, 15... Comparator, 16... D/A converter, 26...
...Oil temperature control circuit. Note that the same reference numerals in the figures indicate the same or equivalent parts. Figure 3 - 556070γ Curved Base (°C) Figure 5 Figure 6 Figure 8

Claims (3)

[Claims] (1) Detect the oil temperature of the hydraulic elevator with an oil temperature sensor,
In an oil temperature detection device for a hydraulic elevator that controls an elevator based on the detection output, when the oil temperature detected by the oil temperature sensor is determined to be abnormal, it controls the operation of the car and also controls the oil temperature at the time of abnormality determination. An oil temperature detection device for a hydraulic elevator, characterized by storing and retaining data. (2) The oil temperature detection device for a hydraulic elevator as set forth in claim (1), wherein the oil temperature data at the time of abnormality determination is stored and retained by a battery even after power is cut off. (3) The oil temperature detection device for a hydraulic elevator according to claim (1), which maintains the operation of the oil temperature control circuit and limits the movement of the car after determining that the detected oil temperature is abnormal. .