JPS6017748B2 - Hydraulic elevator control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a hydraulic elevator, and more particularly to a control device capable of eliminating adverse effects on speed characteristics caused by temperature changes in hydraulic fluid.

As is well known, a hydraulic elevator sends oil discharged from a pump to a cylinder and operates a plunger to raise and lower a car.The flow rate of oil discharged from the pump is controlled by a solenoid valve, choke, etc. Low speed is achieved by bypassing the valve.

However, since the viscosity of the hydraulic fluid in a hydraulic elevator changes with temperature changes, the time point at which it becomes effective changes and the low-speed running time of the Qin car also changes, which adversely affects the speed characteristics. This will be explained in detail with reference to FIGS. 1 to 3.

In Figures 1 and 2, 1 is a hoistway, 2 is a Hata car, 3 is a guide rule for guiding the real car 2, 4 is a guide shoe, 5 is a slope limit switch for commanding deceleration, and 6 is a limit switch. 5 is a bracket for mounting, 7 is a cam for operating the limit switch 5, 8 is a hydraulic cylinder ~ 9 is a plunger, IQ is a tank, 11 is a hydraulic pump, 12 is an electric motor for driving the hydraulic pump 11, 13
14 is a check valve, 14 is a pilot check valve, 15 is a solenoid valve for operating the pilot check valve 14, 15C is a coil thereof, 16 is a choke for adjusting the operating characteristics of the pilot check valve 14, 17 is a pipe connecting the hydraulic cylinder 8 and the check valve 13; 18 and 19 are the hydraulic pump 11;
The discharged oil is passed through the pilot check valve 14 to the tank 101.
There are two pipes and hydraulic oil to bypass this.

When the car 2 reaches the deceleration point R of the destination floor and the cam 7 and the limit switch 5 attached to the car 2 engage, the P-switch 5-coil 16C-N circuit is opened and the coil 15C is activated. When the oil is extinguished, the solenoid valve 15 is activated outside the neutral block, and the pilot reverse valve 14 is opened. The supply of oil to the hydraulic cylinder 8 decreases, and the Qin car 2 becomes low speed and travels at the same speed until a stop command is issued.However,
Since the choke 16 is susceptible to changes in the viscosity of the hydraulic oil 20 due to changes in oil temperature, the temperature difference causes a large difference in low-speed running time. In other words, ``When the oil temperature is low as shown in Figure 3, the low speed S, shown by the solid line, the low speed running time T,
In addition, when the oil temperature is high, the low speed S2 and low speed running time T2 shown by the broken line occur, causing a drop in performance such as landing errors. SUMMARY OF THE INVENTION An object of the present invention is to provide a control device for a hydraulic elevator that eliminates the drawbacks of the prior art described above and can always perform good speed control even when the temperature of hydraulic oil changes.

In order to achieve this object, the present invention provides a plurality of at least one of a switch that issues a deceleration command and a switch actuating body separated by a necessary period, and optionally switches any one of the plurality of switches to a switch. The present invention is characterized in that a switching selection means is provided for selecting one to enable and the other to disable, and the time point at which deceleration of the car is started can be changed by the switching selection.

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5.

In these figures, the same reference numerals as in FIGS. 1 and 2 indicate the same or equivalent parts. The difference from the slave example shown in Figs. 1 and 2 is that two glue mitt switches 5, 52 are provided vertically with a distance K apart from each other, and these parallel circuits are connected in series to the coil j6C of the solenoid valve. The temperature detection section 21a of the temperature switch is provided in the tank 10, and its switching contact section 21b is connected in series to the coil 15C and the limit switch 6. This is the same as the example. When the oil temperature is low, the switching contact part 21b of the temperature switch is on the a-b side, the limit switch 5 is selected, and the P-a-b-5 one coil 1
A circuit of 5c-N is configured.

Therefore, only limit switch 5 becomes effective,
When the limit switch 5 engages with the cam 7, a deceleration command is issued as described above, and the Qin car 2 is brought to a low speed. Next, the oil temperature increases and reaches a certain temperature,
When the temperature detection section 21a of the temperature switch detects this,
The switching contact portion 21b switches to the a-c side, the limit switch 52 is selected, and the P-a-c-52 - coil 15
A C-N circuit is constructed.

Therefore, in this case, the aforementioned limit switch 5
1 is disabled, and the other limit switch 52 located below the limit switch 5 by a distance K becomes effective, and the deceleration shown in FIG. 3 is reduced compared to when the oil temperature is low. Point R can be delayed. For this reason,
By determining the moving distance K of the deceleration point through experiments, it is possible to make the low-speed running time approximately constant regardless of the oil overflow difference. In the embodiment described above, a temperature switch is provided to automatically select the limit switches 5, 52, but this is not necessarily the case. In other words, in the case of commonly used hydraulic fluids, the oil temperature changes that require this kind of switching selection occur only twice, in winter and summer. It is quite possible to obtain. Therefore, a manual switching switch can be used in place of the temperature switch, whereby the oil temperature detection section can be omitted and the apparatus can be made simple and inexpensive. 6 and 7 are examples in which a non-contact relay is used in place of the limit switch and cam.

That is, as shown in FIG.
Positionless relays 221 and 222 are used instead of the cam 7, and a shielding plate 23 of the contactless relay is used instead of the cam 7. Since the other structures and operations are completely the same as those of the previous embodiment, their explanations will be omitted. Also,
In the embodiment described above, a plurality of switches such as limit switches are provided on the Hata car side, and one operating body such as a cam for operating the switch is provided on the hoistway side. Alternatively, it is also possible to use one switch and provide a plurality of switch operating bodies.

In the latter case, a switching mechanism is required to switch the unused switch operating body from the operating position to the non-operating position. As described above, according to the present invention, the low-speed running time can be kept substantially constant regardless of changes in the temperature of the hydraulic oil, and good speed control can always be performed.

Brief explanation of the drawings Figure 1 is an overall configuration diagram of a conventional hydraulic elevator, Figure 2 is a deceleration command circuit diagram of the same hydraulic elevator, Figure 3 is a speed characteristic diagram of the same hydraulic elevator, and Figure 4 is a diagram of the present invention. An overall configuration diagram of a hydraulic elevator equipped with a control device according to one embodiment, FIG. 5 is a deceleration command circuit of the same hydraulic elevator, and FIG. 6 is a partial front view of a control device according to another embodiment of the present invention. 7th
The figure is a partial plan view of the control device.

1...Hoistway, 2...Qin cage, 5,,52
...Limit switch, 7...Cam, 11.
... Hydraulic pump, 13 ... Check valve, 1
4...Pilot check valve, 15...Solenoid valve, 15C...Coil, 16...Choke, 21
a...Temperature detection section of temperature switch, 21b...
・・・・Temperature switch switching contact part, 22, 222・
...Positecta of non-contact relay, 23...
- Shielding plate for non-contact relays.

Figure 1 Figure 2 Figure 3 Figure 5 Figure 7 Figure 4 Figure 6

Claims (1)

[Scope of Claims] 1. A car that goes up and down in a hoistway, a hydraulic pump, a hydraulic cylinder and a plunger that raise the car using pressure oil from the hydraulic pump, and pressure oil from the hydraulic pump. a pipe line for bypassing the pilot oil to the tank via the pilot check valve, a solenoid valve for controlling pilot pressure oil to the pilot check valve, and a switch provided on either the hoistway side or the car side; and a switch actuating body provided on either the hoistway side or the car side, and the actuation of the switch switches and controls the solenoid valve to open the pilot check valve and release pressure oil from the hydraulic pump. In a control device for a hydraulic elevator that decelerates the rising speed of the car by bypassing the tank via the bypass pipe line, a plurality of at least one of the switch and the switch actuating body is provided isolated for a necessary period, and A switching selection means is provided for arbitrarily switching and selecting any one of these plurality of points to make it effective and disabling the others, so that the deceleration opening point of the car can be changed by the switching selection. A control device for a hydraulic elevator, characterized in that: 2. In claim 1, an oil temperature detector is provided to detect when the temperature of the hydraulic oil reaches a predetermined value, and the switching selection is automatically performed based on the detection output of the oil temperature detector. A hydraulic elevator control device characterized by: 3. A control device for a hydraulic elevator according to claim 1, characterized in that a plurality of switches are provided on the car side and one switch operating body is provided on the hoistway side. 4. The control device for a hydraulic elevator according to claim 1, wherein the switch is a limit switch, and the switch operating body is a cam that engages with the switch. 5. The control device for a hydraulic elevator according to claim 3, wherein the switch is a positioner of a non-contact relay, and the switch operating body is a shielding plate that operates the positioner.