JPH075240B2 - Hydraulic elevator valve device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hydraulic elevator apparatus, and more specifically, it includes a raising control valve and a lowering control valve, and controls the amount of oil from a hydraulic pump or an actuator. The present invention relates to a hydraulic elevator valve device that keeps a cage speed at a command value.

[Conventional technology]

As one of elevator drive devices for raising and lowering the cage of an elevator, a hydraulic cylinder is often adopted when the raising and lowering distance of the cage is short. For raising and lowering the cage, one is to directly use the expansion and contraction of the plunger of the hydraulic cylinder, and the other is an indirect type in which a fixed pulley is installed at the upper part of the cage elevating space and a rope is hung on it to increase the expansion and contraction amount of the plunger and raise and lower the cage. There are things.

In any case, by operating an actuator such as a hydraulic cylinder and adjusting the operating speed of the actuator, it is possible to obtain acceleration, constant speed (full speed) and deceleration operation when the cage moves up and down. The amount of supply and discharge of hydraulic oil is controlled by.

In order to control the amount of oil supplied and discharged from the actuator that directly raises and lowers the cage, a case where a hydraulic pilot system is applied to the raising control valve and the lowering control valve of the elevator valve device,
In some cases, an electric control method is applied. These are equipped with a normally open type ascending control valve and a normally closed type ascending control valve, and control the amount of oil from the hydraulic pump or actuator to keep the cage speed at the command value. .

In the former hydraulic pilot system, the spools of the raising control valve and the lowering control valve are adapted to be displaced by the pilot pressure. Each hydraulic pilot circuit has an electromagnetic control valve.By turning the electromagnetic control valve on and off based on an elevator up / down command, the amount of oil supplied to the actuator during ascent or the actuator during descent can be adjusted. The amount of oil discharged from the tank is adjusted.

On the other hand, in the latter electric control method, both the raising control valve and the lowering control valve are electromagnetic control valves, and the solenoid is provided with a pre-stored current pattern to change the degree of excitation, and each control valve directly controls the oil. I try to adjust the amount. Such a latter type of hydraulic elevator valve is described in "Elevator World", Vol. 21, No. 84, page 25, issued by the Japan Elevator Association.

Of the above two types of hydraulic elevator valves, the latter will be taken as an example to explain the control. When raising the cage, when there is a command from the passenger, the hydraulic pump 31 shown in FIG. 20 is driven, and at the same time, for example, the opening command means 32 such as a microcomputer causes an electromagnetic proportional valve which is a lift control valve. A signal for exciting the solenoid 33a of the valve 33 is output. The signal has a pattern that initially increases gradually and gradually to increase the supply amount to the actuator 34.

The opening degree of the raising control valve 33 is kept small so that the actuator 34 expands at a constant total speed after a lapse of a predetermined time. When approaching the deceleration position by raising the cage, the deceleration limit switch operates, and the opening control means 32 causes the raising control valve 33
A signal for weakening the exciting force of the solenoid 33a is output based on the memory pattern so as to gradually increase the opening degree.
When the landing speed reaches about 1/8 to 1/10 of the total speed, a signal for maintaining the opening for a predetermined time is applied to the solenoid 33a.

When the stop limit switch for floor alignment is activated,
The signal from the opening degree instruction means 32 is stopped. Such a signal pattern is, for example, as shown in FIG.
It is a constant trapezoidal current waveform Su that realizes constant velocity Vju and deceleration, and is partially modified so that the landing velocity Vf can be obtained before landing.

When the cage descends, when an instruction is given from the passenger, the opening degree command means 32 outputs an excitation signal of the solenoid 35a of the descending control valve 35. Actuator 34 due to the weight of the cage
However, the signal pattern Sd [see FIG. 21 (b)] is such that the opening degree of the lowering control valve 35 is initially small and gradually increases to increase the amount of oil discharged from the actuator 34. ing. The opening degree of the lowering control valve 35 is kept large so that the actuator 34 contracts at a constant total speed Vjd after a lapse of a predetermined time.

The deceleration limit switch is actuated when approaching the deceleration position when the cage is descending, and the opening command means 32 outputs a signal for weakening the exciting force of the solenoid 35a so as to gradually reduce the opening of the descending control valve 35. . At the landing speed Vf, a signal for maintaining the opening for a predetermined time is applied to the solenoid 35a, and when the stop limit switch for floor alignment is activated, the signal from the opening command means 32 is stopped.

The signal waveform thus operated is similar to the diagram showing the cage speed, and is substantially equal to the oil amount waveform passing through the ascending control valve 33 and the descending control valve 35.

[Problems to be Solved by the Invention]

In any of the elevator valve devices described above, the speed of the cage is determined by the amount of hydraulic oil that passes through the ascending control valve and the descending control valve. If the amount of oil is constantly reproduced, it will be possible to raise and lower the cage while maintaining the desired hoisting speed and riding comfort, but in reality, it operates at the beginning of elevator operation and at the time of subsequent operation. Oil temperature is different. Of course, the oil temperature may change due to the difference in environmental temperature depending on the season.

When the temperature of the hydraulic oil changes, the valve flow rates of the ascending control valve and the descending control valve also change according to the valve opening. If the exciting current of the control valve is kept the same even if the temperature changes, that is, if the valve opening is kept the same, the flow rate passing through the valve generally decreases as the temperature rises. As a result, even if the valve is opened to a desired degree, if the temperature changes, the amount of oil supplied to and discharged from the actuator becomes undesired, and the ascending / descending speed of the cage changes.

The influence of such a temperature change not only changes the amount of oil passing through each control valve, but also affects the volumetric efficiency of the hydraulic pump that supplies hydraulic oil to the actuator. That is, as the temperature rises, the pump discharge rate decreases,
When raising the cage, the opening of the control valve must be adjusted to allow for changes in the pump discharge rate.

As described above, in the hydraulic pilot type hydraulic elevator valve device, for example, a hydraulic pilot type raising control valve for controlling the amount of oil supplied from the hydraulic pump when the cage is raised is adopted. An electromagnetic control valve for applying pressure has conventionally been an on / off valve [see, for example, "Hydraulic pressure and air pressure", Vol. 17, No. 3, page 16].

With such a hydraulic pilot structure, it is almost impossible to finely control the pilot pressure according to the change in oil temperature. Therefore, the acceleration / deceleration, the constant (total) speed, and the landing speed are different depending on the temperature, which has a problem that the mobility of the cage and the riding comfort are affected.

On the other hand, in the hydraulic elevator valve device shown in FIG. 25, which is controlled by the electric waveform signal, the amount of oil supplied to and discharged from the actuator 34 is detected by the flow sensor 36 in the device, and this is converted into a voltage. The differential voltage is further compared with the command voltage signal and the solenoid 33 of the ascending control valve 33 or the descending control valve 35
A predetermined amount of oil is achieved by applying a to 35a.

However, in such feedback control, there is a problem that initial adjustment of proportional, integral, and derivative gains becomes complicated. In addition, if the adjustment is improper, the operation of the ascending control valve and the ascending control valve will be unstable, causing a problem of valve vibration.

In this case, since feedback control is performed to make the supply / discharge amount to the actuator constant, it is not affected by the temperature change as described above, but since the flow rate sensor is built in the elevator valve device, The cost of the device is increased, and the hydraulic elevator valve device becomes extremely complicated.

By the way, Japanese Utility Model Laid-Open No. 58-41759 discloses that when the cage is raised, the set speed designation is output to the main control valve, and the hydraulic oil from the hydraulic pump is bleed off via the main control valve. A control device for a hydraulic elevator is described.

This involves interposing a fixed throttle and an electromagnetic control valve that operates by receiving a preset control signal in a pilot circuit that branches from an oil passage toward the actuator. And
The pressure on the downstream side of the fixed throttle is controlled by the electromagnetic control valve to act as the pilot pressure of the main control valve, and the downstream side pressure is balanced with the spring force arranged on the other side of the main control valve. Are trying to control.

If the number of passengers in the cage now increases, the pressure in the oil passage increases and the downstream pressure also increases, so the valve opening of the main control valve decreases and the cage speed increases. Conversely, if the number of passengers decreases, the speed of the cage will decrease.

In order to prevent the cage speed from changing with respect to such a change in the load state, it is necessary to control the valve opening degree of the electromagnetic control valve according to the load state. In order to achieve this, the flowmeter inserted in the oil passage detects the amount of oil, compares it with the command value, and successively gives a correction value to the electromagnetic control valve to adjust the valve opening of the main control valve. There is.

This is a flow rate feedback control, and as in the above-mentioned example, there are drawbacks that initial adjustment is complicated, a highly sensitive detection function is imposed on the flow meter, and stable operation cannot be expected sufficiently.

The present invention has been made in view of the above problems, and an object thereof is to be applicable to a hydraulic elevator valve device that adopts a hydraulic pilot system, and to avoid the trouble of electric adjustment by adopting an electric open control system that does not require gain adjustment. That is, even if the temperature of the hydraulic oil changes, the amount of oil passing through each control valve is set to a desired value, and acceleration of the cage, deceleration, high running speed and landing speed can be secured. The pilot system is to provide a hydraulic elevator valve device that can obtain stable control characteristics with good linearity that does not depend on load pressure, as an electromagnetic proportional flow rate control method using an electromagnetic pressure reducing valve and a downstream fixed throttle.

[Means for Solving the Problems]

The present invention includes a normally open type ascending control valve and a normally closed type ascending control valve, and adjusts the opening of each valve to control the amount of oil from a hydraulic pump or an actuator. It is applied to the hydraulic elevator valve that keeps the speed of the.

As for the feature, referring to FIG. 1, a check valve 14 is interposed in an oil passage 16 connected to an actuator 6 for moving up and down the hydraulic pump 4 and the cage 5, and the hydraulic pump side with the check valve 14 as a boundary. A bleed-off circuit in which a normally open type rising control valve 2 is arranged is provided branching from the oil passage. An ascending hydraulic pilot circuit that applies a pilot pressure to the pilot chamber 2A of the ascending control valve 2 is provided in parallel with the bleed-off circuit in a continuous manner with the oil passage on the hydraulic pump side. The lifting hydraulic pilot circuit receives a control signal to control the opening of the lifting electromagnetic proportional pilot valve 7 having a pressure reducing valve structure, and the secondary electromagnetic proportional pilot valve 7 located downstream of the secondary electromagnetic proportional pilot valve 7. An upstream downstream fixed throttle 8 that regulates the amount of pilot oil according to the pressure and an upstream upstream fixed throttle 9 that generates a differential pressure between the upstream and downstream from the pilot flow generated by the downstream downstream fixed throttle 8 are interposed. To be dressed. And the pilot chamber of the raising control valve 2
The downstream pressure P1 of the upstream upstream fixed throttle 9 is introduced into 2A as a pilot pressure, and the upstream pressure of the upstream upstream fixed throttle 9 is introduced into the bleed-off chamber 2B facing the pilot chamber 2A.
Pp is being introduced.

On the other hand, an exhaust circuit in which a normally closed type descent control valve 3 is arranged is provided branching from an oil passage on the actuator side with the check valve 14 as a boundary. A lowering hydraulic pilot circuit for applying a pilot pressure to the pilot chamber 3A of the lowering control valve 3 is arranged in parallel with the exhaust circuit in a manner connected to the actuator-side oil passage. The descending hydraulic pilot circuit has a reducing electromagnetic proportional pilot valve 10 whose opening is adjusted by receiving a control signal, and a secondary electromagnetic proportional pilot valve 10 located downstream of the secondary electromagnetic proportional pilot valve 10. The downstream fixed throttle 11 for descending that regulates the amount of pilot oil according to the pressure, and the upstream fixed throttle 12 for descending that is located upstream and generates a differential pressure between the pilot flow generated by the downstream fixed throttle 11 for descending before and after. To be dressed. Then, in the pilot chamber 3A of the descending control valve 3, a descending upstream fixed throttle is installed.
The downstream side pressure P3 of 12 is introduced as a pilot pressure, and the upstream side pressure P of the descending upstream fixed throttle 12 is introduced into the exhaust chamber 3B facing the pilot chamber 3A. An opening degree command means 23 is provided for outputting the solenoid drive signal of the pattern as an open loop control signal to each electromagnetic proportional pilot valve 7, 10.

Further, oil temperature detecting means 25 for detecting the temperature of the hydraulic oil is installed in the hydraulic circuit. Based on the temperature signal from the oil temperature detection means 25, the opening degree command means 23 receives a solenoid drive signal in which the valve flow rate when the cage is raised is compensated and the volumetric efficiency of the hydraulic pump 4 is compensated. An ascending signal correction unit 26 for outputting and a descending signal correction unit 27 for outputting a solenoid drive signal in which the valve flow rate when the cage is descending are provided.

[Action]

When there is a command to raise the cage 5, the opening degree of the electromagnetic proportional pilot valve 7 for raising of the pressure reducing valve structure is adjusted according to a command pattern which is an open loop control signal from the opening command means 23. As a result, a predetermined pilot pressure P1 is generated in the raising hydraulic pilot circuit of the raising control valve 2, and the opening of the raising control valve 2 is increased by the pressure difference Pp-P1 acting before and after the valve body of the raising control valve 2. Is adjusted.

A part of the total amount of oil introduced from the hydraulic pump 4 to the raising control valve 2 and bleeding off is supplied to the actuator 6, and the cage 5 rises. The opening degree of the raising control valve 2 is adjusted in accordance with a command pattern for driving the solenoid of the raising electromagnetic proportional pilot valve 7, and the actuator 6
The cage 5 rises according to the amount supplied to the cage.

The case of lowering the cage 5 is almost the same, and the opening degree of the lowering control valve 3 is adjusted based on a command pattern for driving the solenoid of the lowering electromagnetic proportional pilot valve 10 of the pressure reducing valve structure. The amount of oil discharged from the actuator 6 flows into the tank 13 according to the opening degree of the descending control valve 3, and the descending speed according to the command pattern is given to the cage 5.

In the above operation, if the temperature of the hydraulic oil changes, the amount of oil supplied to and discharged from the actuator and the amount of oil discharged from the hydraulic pump will change even if the opening degree of each control valve 2, 3 is set as instructed. It will come. Therefore, when the cage 5 rises, the solenoid that compensates the valve flow rate and the volumetric efficiency of the hydraulic pump 4 in the raising signal correction unit 26 based on the temperature signal from the oil temperature detecting means 25. The drive signal is output.

Therefore, the valve opening of the rising electromagnetic proportional pilot valve 7 is adjusted based on the correction pattern according to the temperature change, and the bleed-off amount of the rising control valve 2 determined by the pilot pressure generated by the valve opening is used to drive the actuator. The supply amount to No. 6 is set to a desired value regardless of the oil temperature.

On the other hand, when the cage 5 descends, the solenoid signal for compensating the valve flow rate is output in the descending signal correcting section 27 based on the temperature signal from the oil temperature detecting means 25. Therefore, the amount of oil discharged from the actuator 6 at the time of descending is adjusted by the valve opening degree of the descending electromagnetic proportional pilot valve 10 based on the correction pattern according to the change in temperature, and the flow from the descending control valve 3 to the tank 13 is adjusted. The amount has a desired value regardless of the oil temperature.

〔The invention's effect〕

According to the present invention, the differential pressure across the upstream fixed throttle is controlled by the ascending electromagnetic proportional pilot valve or the descending electromagnetic proportional pilot valve and its downstream fixed throttle, and the downstream pressure of the upstream fixed throttle upstream and downstream differential pressure is increased. Control valve and lowering control valve into the pilot chamber, upstream pressure is introduced into the oil chamber facing each pilot chamber, and the valve opening of the rising and lowering control valves is adjusted by this pressure balance. You will be able to decide.

The ascending electromagnetic proportional pilot valve and the descending electromagnetic proportional pilot valve are electromagnetic proportional pressure reducing valves with a pressure reducing valve structure whose opening is adjusted by receiving a control signal.The secondary pressure is controlled regardless of the primary pressure, and the downstream fixed throttle valve is used. With, it is possible to control the pilot flow rate according to the command regardless of the primary pressure.

Therefore, even if the number of passengers changes and the load pressure changes, the pressure before and after the upstream fixed throttle does not change, and the differential pressure can be changed only by the command current of the rising electromagnetic proportional pilot valve and the falling electromagnetic proportional pilot valve. Can be decided

Further, all the electromagnetic proportional pilot valves are also electromagnetic proportional pressure reducing valves, and the fixed throttles are arranged upstream and downstream thereof, so that the differential pressure characteristic with respect to the command current becomes linear.
In this way, since a stable differential pressure characteristic having good linearity that does not depend on the load pressure can be obtained, the open loop control can be performed only by the signal from the opening degree commanding means. This eliminates the need for gain adjustment required for foot-back control, thus avoiding the troublesome electric adjustment in the initial adjustment work of the apparatus.

Further, even if the oil temperature changes, the amount of oil supplied to the actuator when rising and the amount of drained oil that passes through the lowering control valve when falling can be set to desired values. Therefore, even in the hydraulic pilot type elevator valve, it is possible to always give a desired acceleration / deceleration to the cage, and to drive the cage at high speed and at low speed.

〔Example〕

Hereinafter, the present invention, based on the drawings showing the embodiment,
The details will be described. FIG. 1 is a hydraulic circuit diagram of a hydraulic elevator valve device 1 adopting a hydraulic pilot system.

This is equipped with a normally open type ascending control valve 2 and a normally closed type ascending control valve 3, and by adjusting the opening of each of these valves 2 and 3, the hydraulic pump 4 and cage 5 are moved up and down. The amount of oil from the actuator 6 such as a hydraulic cylinder to be controlled is controlled to adjust the speed of the cage 5 to a command value.

A check valve 15 is provided in a main oil passage 16 for supplying hydraulic oil from the hydraulic pump 4 to the actuator 6 for moving the cage 5 up and down. The ascending control valve 2 is arranged in a bleed-off circuit that branches from the oil passage on the hydraulic pump side with the check valve 14 as a boundary, and the descending control valve 3 as a boundary with the check valve 14 as a boundary. It is arranged in the exhaust circuit that branches from the oil passage on the actuator side.

In such an elevator valve device, a rising hydraulic pilot circuit that applies pilot pressure to the pilot chamber 2A of the rising control valve 2 is arranged in parallel with the bleed-off circuit and is connected to the oil passage on the hydraulic pump side. Further, a descending hydraulic pilot circuit that applies a pilot pressure to the pilot chamber 3A of the descending control valve 3 is also provided in parallel with the exhaust circuit.

The rising hydraulic pilot circuit is provided with a rising electromagnetic proportional pilot valve 7 having a pressure reducing valve structure, the opening of which is adjusted in response to a control signal, and a downstream fixed throttle 8 for rising. Further, there is provided a rising upstream fixed throttle 9 for generating a pilot pressure P1 by the pilot flow generated in the lifting hydraulic pilot circuit and for causing the pressure to act on the pilot chamber 2A of the rising control valve 2.

On the other hand, the descending hydraulic pilot circuit is provided with a descending electromagnetic proportional pilot valve 10 of a pressure reducing valve structure whose opening is adjusted in response to a control signal and a descending downstream fixed throttle 11. Further, there is provided an upstream fixed throttle 12 for descending, which generates a pilot pressure P3 by a pilot flow generated in the descending hydraulic pilot circuit and acts the pilot pressure P3 on the pilot chamber 3A of the descending control valve 3.

Therefore, when the cage 5 rises, the remaining amount of the hydraulic oil supplied from the hydraulic pump 4 that has been bleed-off to the tank 13 according to the valve opening degree of the raising control valve 2 is the check valves 14 and 15. The hydraulic oil is supplied to the hydraulic cylinder 6 via the above, and the amount of hydraulic oil is adjusted. In addition, check valve
Reference numeral 14 is for preventing the hydraulic oil from the hydraulic cylinder 6 from being introduced into the raising control valve 2 when the cage 5 descends.

The pilot pressure P1 applied to the above-mentioned raising control valve 2 is
It is generated as follows. When the rising electromagnetic proportional pilot valve 7 is opened, the pressure on the secondary side of the reducing electromagnetic proportional pilot valve 7, which is a pressure reducing valve structure, does not depend on the pressure P1 on the primary side, and the secondary pressure depends on the valve opening degree. The pressure P2 is regulated while taking the feedback of. The amount qu of oil passing through the upstream fixed downstream throttle 8 is determined according to the secondary pressure P2. That is, the amount of oil qu passing through the fixed downstream fixed throttle 8 changes in proportion to the opening of the rising electromagnetic proportional pilot valve 7.

The pilot flow passes through the upstream upstream fixed throttle 9 downstream of the filter 17, which is interposed upstream of the hydraulic upstream pilot circuit, and the flow thereof causes a differential pressure before and after the upstream upstream fixed throttle 9. That is, the pressure P1 on the downstream side of the rising upstream fixed throttle 9 becomes lower than the pressure Pp in the oil passage 16 through which the hydraulic oil from the hydraulic pump 4 is supplied to the hydraulic cylinder 6. Since this front-to-back differential pressure Pp-P1 changes in proportion to the opening of the rising electromagnetic proportional pilot valve 7, the opening of the rising control valve 7 is adjusted using this differential pressure.

The pressure P1 on the downstream side of the rising upstream fixed throttle 9 acts on the spring chamber 2A which is a pilot chamber of the rising control valve 2, and the bleed-off chamber 2B facing the spring chamber 2A with the piston 2a interposed therebetween is The pressure Pp of the oil passage 16 acts. Due to the spring, the piston 2a of the lift control valve 2 that was in the fully open state is displaced, the spool moves, the valve opening decreases, and the bleed-off chamber 2B
The amount of oil that is bleed off to the tank 13 via the oil is reduced. Therefore, the amount of oil supplied from the oil passage 16 to the hydraulic cylinder 6 is increased accordingly.

On the other hand, the pilot flow of the descending control valve 3 is generated by the descending electromagnetic proportional pilot valve 10 and its descending downstream fixed throttle 11, and the flow of the descending upstream fixed throttle 12 provided downstream of the filter 18 is generated. A differential pressure P-P3 is generated in the front and rear, and the pressure P3 on the downstream side of the differential pressure P-P3 is a spring chamber that is a pilot chamber of the descending control valve 3.
Acts as pilot pressure on 3A.

The exhaust chamber 3B, which faces the piston 3a with the piston 3a in between, is supplied with the working oil of the pressure P returned from the hydraulic cylinder 6.
With the pilot pressure P3 acting on the spring chamber 3A, the valve opening of the lowering control valve 3 is adjusted, and the amount of hydraulic oil discharged from the hydraulic cylinder 6 is controlled.

An electromagnetic pilot switching valve 20 that opens upon receiving a downward command for the throttle 19 and the cage 5 is interposed in a circuit that bypasses the check valve 15. The electromagnetic pilot switching valve 20 opens immediately when there is a command to lower the cage 5. As described above, the pilot pressure P3 is generated by the flow of the hydraulic oil from the hydraulic cylinder 6 through them, but the check valve 15 is also opened according to the opening operation of the lowering control valve 3 and is discharged. Most of the hydraulic oil flows from the check valve 15 to the tank 13 via the lowering control valve 3.

By the way, an emergency manual valve 21 for directly draining the hydraulic oil from the hydraulic cylinder 6 and lowering the cage 5 to the bottom in an emergency is provided in a circuit directly connected to the tank 13.

Such a hydraulic elevator valve device is built in the valve casing 22 as shown by the chain double-dashed line in the figure, forming an integral valve mechanism. Therefore, three ports P, T, and C are opened in the valve casing 22, and the respective pipings are connected.

By the way, the solenoid proportional pilot valve 7 for ascent and the solenoid proportional pilot valve 10 for descending are respectively connected to the solenoid 7
Although a and 10a are excited to change their opening, opening instruction means 23 for generating the excitation signal is installed.

This is composed of a microprocessor or the like, and when there is a command to move the cage 5 up and down, it receives a command signal from a separately installed controller 24 that controls the hydraulic elevator valve device,
It outputs an electric signal according to a command pattern described later. Further, it is composed of a central processing unit, a fixed storage unit, a writing storage unit, a timer, and the like, and the fixed storage unit has a structure for acceleration / deceleration as shown by the solid line in FIGS. The command pattern is stored.

The pattern is a current waveform, and each waveform is preliminarily smoothly shaped so that the portions indicated by arrows Xu, Yu, Zu, Xd, Yd, and Zd in the figure are S-shaped curves. When the solenoid drive command signal is received, the cage 5 is shown in FIG. 3 (a).
And as shown in (b), the desired acceleration state during the ascent and descent, the full-speed state of the speeds Vu, Vd and the deceleration state,
Moreover, when the vehicle moves from acceleration to high speed or from deceleration to low speed, it is possible to obtain a good ride comfort.

An oil temperature detecting means 25 for detecting the temperature of the hydraulic oil is installed in a part of the oil passage of the above-mentioned valve casing 22, in the vicinity of the tank port T in FIG. This is, for example, a thermistor, and is used to make adjustments when the temperature of the hydraulic oil differs between the beginning of elevator operation and the subsequent operation, or the oil temperature changes due to the difference in environmental temperature depending on the season. belongs to.

The opening command means 23 is a solenoid drive in which the valve flow rate when the cage is raised is compensated and the volumetric efficiency of the hydraulic pump 4 is compensated based on the temperature signal from the oil temperature detection means 25. A rising signal correction unit 26 that outputs a signal and a falling signal correction unit 27 that outputs a solenoid drive signal in which the valve flow rate when the cage is moving down are provided.

The temperature compensation will be described in detail below. As shown in FIG. 4, when the solenoid drive currents Id1, Id2, Id3, ... Of the solenoid proportional pilot valve 10 for lowering are kept constant without temperature compensation, the corresponding control valve 3 for lowering
Each of the passing oil amount Qd1, Qd2, Qd3 ··· decreases with increasing temperature.

In order to make the oil quantities Qd1, Qd2, Qd3 ... Constant regardless of the temperature, the exciting currents Id1, Id2, Id3 ... May be increased as the temperature rises, as shown in FIG. In this case, the exciting current applied to the descending electromagnetic proportional pilot valve 10 is as shown by the broken line when the oil temperature is higher than the pattern at the standard temperature as shown by the solid line in FIG. When the oil temperature is low, the current at each time is increased or decreased as shown by the one-dot chain line pattern. In this way, when the exciting current pattern is corrected by the descending signal correcting unit 27 according to the oil temperature, the same downward movement of the cage 5 is always achieved as shown in FIG. 3 (b).

The above is the control of the amount of oil discharged from the hydraulic cylinder 6 when the cage is lowered when the hydraulic pump 4 does not operate.
When the oil pressure rises, the hydraulic pump 4 operates, so that it is also necessary to compensate its volumetric efficiency according to the oil temperature. Similarly to the above, in the opening operation of the rising electromagnetic proportional pilot valve 7, the following correction is added to the correction to the same effect as in FIG. 5 due to the change in oil temperature.

The discharge amount Qp of the hydraulic pump 4 decreases as the oil temperature rises as shown by the solid line in FIG. In order to supply the constant oil temperature Qu2 to the hydraulic cylinder 6 as indicated by the broken line even if the temperature changes, it is necessary to decrease the bleed-off amount Qu1 in the raising control valve 2 as the oil temperature rises. In order to reduce the opening degree of the raising control valve 2, it is necessary to increase the opening degree of the raising electromagnetic proportional pilot valve 7. Therefore, the solenoid exciting current of the raising electromagnetic proportional pilot valve 7 must be increased. I won't.

As a result, the rising signal correction unit 26 is adjusted so as to output a drive current that takes into consideration the compensation of the valve flow rate characteristic due to the change of the oil temperature and the compensation of the change of the volumetric efficiency of the hydraulic pump 4. For the drive currents Iu1, Iu2, Iu3 ··· as shown in Fig. 7, the bleed-off amounts Qu11, Qu12, Qu13 · · of the rising control valve 2
Is obtained, and even if the temperature of the hydraulic cylinder 6 changes, a constant amount of supplied oil Qu21, Qu22, Qu23 ... Is realized.

When the pattern of the exciting current according to the oil temperature is changed by the rising signal correction unit 26, the same rising motion of the cage 5 is always achieved as shown in FIG. In addition,
The flow rate characteristic with respect to the temperature of each control valve 2, 3 and the temperature characteristic of the volumetric efficiency of the hydraulic pump 4 are grasped in advance, and the data for correcting the solenoid drive current based on the characteristic is stored in the opening command means 23. It is stored in the rising signal correction unit 26 and the falling signal correction unit 27.

By the way, the change in the volumetric efficiency of the hydraulic pump 4 has a great influence when the above-mentioned increase due to the landing speed, that is, when the amount of oil supplied to the hydraulic cylinder 6 is small, and the correction effect is remarkably exhibited at that speed. It

The operation sequence with the above configuration will be described below. First, the raising control valve 2 is normally open, and the spring 2b
By the action of, the piston 2a is pressed and the valve is fully opened.

When a rising command is issued, the hydraulic pump 4 is activated [see FIG. 8], and commands for operation, high speed rising, and low speed rising are input to the controller 24 [FIG. 9 (a), FIG. 10 (a)]. And FIG. 11 (a)]. Now, the raising control valve 2 is in the fully open state, and the amount of hydraulic oil from the hydraulic pump 4 is all in the tank 13
Has been bleeded off (see Fig. 12).

The oil temperature detection means 25 detects the temperature of the hydraulic oil and the signal
As shown in the block diagram of FIG. 13, the opening command means is converted into a digital signal from the controller 24 through the interface 28 together with the command signal for the above-mentioned operation or high speed rising.
Entered in 23. In the opening degree commanding means 23, the command pattern shown in FIG. 2 (a) stored in advance in accordance with the temperature signal is a broken line or one-dot chain line pattern in consideration of the valve characteristic and the volumetric efficiency of the hydraulic pump 4. Is corrected and converted into an analog signal.

When the solenoid-excited current is output by the voltage-current converter 29 having the constant current characteristic, and the rising electromagnetic proportional pilot valve 7 is opened by the current, the secondary side pressure P2 corresponding to the opening is defined. An amount of oil qu passing through the rising downstream fixed throttle 8 is generated according to the pressure, and a differential pressure is generated before and after the rising upstream fixed throttle 9.

When the opening degree of the ascending electromagnetic proportional pilot valve 7 changes, the differential pressure Pp-P1 further increases and the bleed-off amount of the ascending control valve 2 is gradually reduced. That is, the solenoid exciting current of the rising electromagnetic proportional pilot valve 7 is
It increases during t3 [see FIG. 2 (a)], and when the pilot flow rate qu passing through the ascending downstream fixed throttle 8 increases [14th
[Fig.], Pressure P2 on the upstream side of the downstream fixed throttle 8 for rising
Also increases [see Figure 15].

Therefore, the pump pressure Pp (see FIG. 16) before and after the upstream upstream fixed throttle 9 downstream of the filter 17 interposed in the hydraulic hydraulic pilot circuit provided in the oil passage 16 and the electromagnetic proportional pilot valve 7 for upstream Upstream pressure P1 (see Fig. 17)
And the differential pressure Pp-P1 increases.

Since the pressure P1 acting on the spring chamber 2A is lower than the pressure Pp acting on the bleed-off chamber 2B, the raising control valve 2 operates in the closing direction. As a result, the pressure Pp in the oil passage 16 gradually increases [see FIG. 16], and when the pressure Pc slightly higher than the pressure Pc corresponding to the weight of the cage 5 acting on the hydraulic cylinder 6 and the occupant, the check valve 15 Is opened, the supply of hydraulic oil to the hydraulic cylinder 6 is started, and the cage 5 starts to move upward (see FIG. 3 (a)).

Furthermore, an S-shaped command pattern Xu [see FIG. 2 (a)]
Accordingly, when the solenoid drive current increases, the raising control valve 2 operates in the direction of further closing, and the bleed-off flow rate Qu1 of the raising control valve 2 gradually decreases [see FIG. 12], while the supply to the hydraulic cylinder 6 is continued. The flow rate Qu2 increases [18th
The cage 5 is smoothly accelerated [see FIG. 3 (a)]. Next, the command pattern is the predetermined high-speed current Iu
t [see FIG. 2 (a)], the hydraulic cylinder 6 extends at high speed, and the cage 5 rises at speed Vu [FIG. 3 (a)].
reference〕.

When the cage 5 approaches the upper floor, the deceleration limit switch operates, so that the high-speed rising signal in the controller 24 is cut off [see FIG. 10 (a)], and only the low-speed rising signal remains [Fig. 11 ( a)], the solenoid exciting current of the ascending electromagnetic proportional pilot valve 7 follows an S-shaped pattern Yu [see FIG. 2 (a)], and operates the ascending control valve 2 in the opening direction. As a result, the supply flow rate Qu2 to the hydraulic cylinder 6 decreases (see FIG. 18), while the bleed-off flow rate Qu1 of the raising control valve 2 increases (see FIG. 12),
The cage 5 is decelerated [see FIG. 3 (a)].

Next, the command pattern becomes a predetermined low-speed current Iui [see FIG. 2 (a)], and a low speed, that is, an ascending state due to the landing speed Vf [see FIG. 3 (a)]. When the stop limit switch for floor alignment is operated, the low speed rising signal of the controller 24 is also cut off (see FIG. 11 (a)), and the command current is a predetermined S-shaped command pattern Zu (see FIG. 12 (a)). Decrease according to. The raising control valve 2 bleeds off the total discharge amount Qp of the hydraulic pump 4 [see FIG. 12], and the cage 5 stops [see FIG. 3 (a)].

In order to mitigate the shock when the cage 5 stops, the hydraulic pump 4 is stopped after a certain short time elapses from the stop command after the cage 5 completely stops [see FIG. 8]. ].

The descending control valve 3 is normally closed, the piston 3a is being pressed by the action of the spring 3b, and the valve is fully closed. When there is a command to lower the cage 5, the hydraulic pump 4 is not driven [see FIG. 8], and the operation, high speed lowering, and lower speed lowering signals are input to the controller 24 [FIG. 9 (b), 10]. See FIG. (B) and FIG. 11 (b)].

The solenoid 20a of the electromagnetic pilot switching valve 20 is excited by a signal from the controller 24 [see FIG. 19], the electromagnetic pilot switching valve 20 is opened, and the hydraulic oil from the hydraulic cylinder 6 flows through the throttle 19. The pressure P in the oil passage 16 rises (see FIG. 20). In this state, the temperature signal from the oil temperature detecting means 25 is input to the opening degree commanding means 23 via the controller 24, and the drive current gradually increases according to the temperature-corrected command pattern [see FIG. 2 (b)]. ].

The solenoid excitation of the descending electromagnetic proportional pilot valve 10 is increased, and the secondary side pressure P4 is specified according to the opening degree (see FIG. 21). Downstream fixed throttle for descending according to the pressure
An oil amount qd passing through 11 is generated (see FIG. 22), and a differential pressure is generated before and after the descending upstream fixed throttle 12. When the opening degree of the descending electromagnetic proportional pilot valve 10 changes, the differential pressure P-P3 thereof further increases, and the amount of oil passing through the descending control valve 3 gradually increases.

That is, the solenoid exciting current of the descending electromagnetic proportional pilot valve 10 increases (see FIG. 2 (b)), and the pilot flow rate qd passing through the descending downstream fixed throttle 11 increases [22nd
The pressure P4 on the upstream side of the downstream fixed throttle 11 also increases [see FIG. 21].

As a result, the pressure P of the oil passage 16 (see FIG. 20) before and after the downstream fixed upstream throttle 12 downstream of the filter 18 interposed in the hydraulic pilot circuit provided in the oil passage 16 and the solenoid proportional pilot valve for lowering. The pressure difference P-P3 with the upstream pressure P3 of 10 (see FIG. 23) increases.

Since the pressure P3 acting on the spring chamber 3A is lower than the pressure P acting on the exhaust chamber 3B, the lowering control valve 3 operates in the opening direction. The check valve 15 opens according to the opening operation of the lowering control valve 3. Command current is S of command pattern Xd
According to the letter shape [see FIG. 2 (b)], the control flow rate Qd of the descending control valve 3 increases [see FIG. 24], and the cage 5
Is accelerated [see FIG. 3 (b)].

Next, the command pattern becomes a predetermined high-speed current Idt [second
The cage 5 descends at a high speed Vd (see FIG. 3B) (see FIG. 3B). When the cage 5 approaches the lower floor, the deceleration limit switch operates, the high speed descending signal of the controller is cut off (see Fig. 10 (b)), and the current of the descending solenoid proportional pilot valve 10 is gradually decreased according to the command pattern Yd. [Second
(See FIG. 2B), the lowering control valve 3 is operated in the closing direction. The control flow rate Qd of the descending control valve 3 decreases [see FIG. 24], and the cage 5 is decelerated [see FIG. 3 (b)].

Next, the command pattern becomes a predetermined low-speed current Idi [second
(See FIG. 3B)], and a low speed running state is set [see FIG. 3B]. When the stop limit switch for floor alignment operates, the low-speed falling signal of the controller 24 is cut off (see FIG. 11 (b)), and the command current decreases in the S-shaped stop pattern of the predetermined pattern Zd [FIG. 2]. (See (b)], the lowering control valve 3 is gradually closed from the closing operation.

In order to mitigate the shock when the cage 5 stops, the solenoid drive signal of the electromagnetic pilot switching valve 20 has a certain short time after the stop command after the lowering control valve 3 is completely closed. Will be shut off (see Fig. 19).

As can be seen from the above description, the differential pressure Pp-P1 across the rising upstream fixed throttle 9 is adjusted by receiving a control signal and the opening is adjusted. 8 and controls the downstream pressure P1 by the downstream fixed throttle 8 for raising the pilot chamber 2A of the raising control valve 2
On the other hand, the throttle upstream pressure Pp is applied to the pilot chamber 2A.
Since the bleed-off chamber 2B is opposed to the bleed-off chamber 2B, the valve opening degree of the raising control valve 2 is determined by the equilibrium of the pressure.

The rising electromagnetic proportional pilot valve 7 is an electromagnetic proportional pressure reducing valve. The secondary pressure P2 is controlled regardless of the primary pressure P1 of the rising electromagnetic proportional pilot valve 7, and the rising downstream fixed throttle 8
The pilot flow rate qu defined by is also controlled independently of the pressure P1. Therefore, the oil passage 16
Differential pressure across the upstream fixed upstream throttle 9 even if the pressure Pp changes
Pp-P1 does not change and can be determined only by the command current of the ascending electromagnetic proportional pilot valve 7.

Further, since the fixed throttle 9 is arranged upstream of the rising electromagnetic proportional pilot valve 7 of the pressure reducing valve structure and the fixed throttle 8 is arranged downstream thereof, the upstream fixed throttle 9 for rising with respect to the command current of the electromagnetic proportional pilot valve 7 for rising. The characteristic of the differential pressure Pp-P1 across is linear. In this way, open loop control that can obtain a stable differential pressure Pp-P1 that does not depend on the load pressure can be achieved, and therefore the troublesome initial adjustment of the device, which is necessary for feedback control, can be eliminated.

In addition, even if the oil temperature changes, the amount of oil supplied to the actuator and the amount of oil passing through the descent control valve can be set to predetermined values, and acceleration / deceleration of the cage and high-speed and low-speed running can be maintained at desired values. To be done.

Further, since the solenoid drive command signal having an ascending or descending pattern with an S-curve pattern during acceleration / deceleration is output to each of the electromagnetic proportional pilot valves, the command signal for shifting from acceleration or deceleration to low speed is It is smooth and improves the ride comfort of the cage.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a hydraulic elevator valve device according to the present invention, and FIG.
3 (a) and 3 (b) are solenoid drive signal waveform diagrams of an ascending electromagnetic proportional pilot valve and an ascending electromagnetic proportional pilot valve whose opening is adjusted by receiving a control signal output from the opening command means, FIG. (A) and (b) are the cage up-and-down velocity diagrams,
FIG. 4 is a change diagram of the amount of oil passing through the lowering control valve when a solenoid drive current without temperature compensation is applied to the electromagnetic proportional pilot valve, and FIG. 5 is a solenoid drive pilot for lowering the temperature-compensated solenoid drive current. FIG. 6 is a diagram of the amount of oil passing through the valve in the lowering control valve when applied to the valve, FIG.
FIG. 7 is a diagram of a solenoid drive current applied to a rising electromagnetic proportional pilot valve by temperature compensation, a change in the amount of oil bleed-off from the rising control valve in response to it, and a diagram of the amount of oil supplied to the actuator by the bleed-off amount. FIG. 8 is an operation state diagram of the hydraulic pump, FIGS. 9 (a) and 9 (b) are operation signals input to the controller, and FIGS. 10 (a) and 10 (b).
Is a high speed up / down signal input to the controller, FIGS. 11 (a) and 11 (b) are low speed up / down signals input to the controller, FIG. 12 is a change state diagram of the bleed-off amount in the raising control valve, FIG. 13 Is a block diagram for outputting a solenoid drive signal corrected by the detection signal from the oil temperature detecting means, FIG. 14 is a change state diagram of the pilot control oil amount at the time of ascent, and FIG. 15 is a downstream of the ascending electromagnetic proportional pilot valve. Change diagram of control pressure, Fig. 16 is a change diagram of pressure in the oil passage downstream of the hydraulic pump, Fig. 17 is a change diagram of pilot control pressure of the raising control valve, and Fig. 18 is hydraulic oil supplied to the hydraulic cylinder. Fig. 19 is a diagram showing the amount of change, Fig. 19 is a diagram showing the opening of the electromagnetic pilot switching valve, Fig. 20 is a diagram showing changes in the pressure in the return oil passage from the hydraulic cylinder, and Fig. 21 is the downstream control pressure of the descending electromagnetic proportional pilot valve. Change diagram, Fig. 22 descends Fig. 23 is a diagram showing changes in the pilot control oil amount, Fig. 23 is a diagram showing changes in the pilot control pressure of the lowering control valve, Fig. 24 is a diagram showing changes in the controlling amount by the lowering control valve during lowering, and Fig. 25 is an electrical diagram. An example of a hydraulic elevator valve device according to the prior art by feedback control, FIGS. 26 (a) and 26 (b) are speed change diagrams of a vertically moving cage. 2 ... Rise control valve, 2A ... Pilot chamber (spring chamber),
2B ... Bleed-off chamber, 3 ... Descent control valve, 3A ... Pilot chamber (spring chamber), 3B ... Exhaust chamber, 4 ...
Hydraulic pump, 5 ... Cage, 6 ... Actuator (hydraulic cylinder), 7 ... Ascending solenoid proportional pilot valve, 8
...... Upstream fixed throttle for rising, 9 …… Upstream fixed throttle for rising,
10 …… electromagnetic proportional pilot valve for descending, 11 …… downstream fixed throttle for descending, 12 …… upstream fixed throttle for descending, 23 …… opening command means, 25 …… oil temperature detecting means, 26 …… rising signal Correction unit,
27 …… Descent signal compensator, P1, P3 …… Pilot pressure.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-57-126378 (JP, A) JP-A-60-129404 (JP, A) Actual opening 58-41759 (JP, U) Actual opening Sho-57- 144970 (JP, U)

Claims (1)

[Claims] 1. A normal open type ascending control valve and a normally closed type ascending control valve are provided, and the opening of each valve is adjusted to control the amount of oil from a hydraulic pump or actuator, respectively. In a hydraulic elevator valve that keeps the speed of a cage at a command value, a check valve is provided in an oil passage connected to the hydraulic pump and an actuator that moves the cage up and down, and an oil passage on the hydraulic pump side with the check valve as a boundary Is provided with a bleed-off circuit in which the normally open type rising control valve is arranged, and the rising hydraulic pilot circuit that applies pilot pressure to the pilot chamber of the rising control valve is connected to the oil on the hydraulic pump side. Of the pressure reducing valve structure, which is arranged in parallel with the bleed-off circuit in parallel with the road, and whose opening is adjusted by receiving a control signal in the ascending hydraulic pilot circuit. An ascending electromagnetic proportional pilot valve, a downstream fixed throttle for ascending which regulates the amount of pilot oil according to the secondary pressure generated by the ascending electromagnetic proportional pilot valve, and an ascending upstream upstream throttle valve. A fixed upstream upstream restrictor for generating a differential pressure between the pilot flow generated by the downstream fixed upstream throttle and the upstream upstream fixed restrictor is installed in the pilot chamber of the upstream control valve. The upstream side pressure of the upstream fixed upstream throttle is introduced into the bleed-off chamber facing the pilot chamber, and the pressure is branched from the oil passage on the actuator side with the check valve as a boundary. And an exhaust circuit in which the normally closed type lowering control valve is arranged is provided, and a pilot pressure is applied to the pilot chamber of the lowering control valve. Hydraulic pilot circuit is arranged in parallel with the exhaust circuit in series with the hydraulic passage on the actuator side, and the hydraulic pilot circuit for lowering has a reducing electromagnetic proportional pilot of a pressure reducing valve structure for adjusting the opening in response to a control signal. A valve, a downstream fixed throttle for descending that regulates the amount of pilot oil according to the secondary pressure generated by the electromagnetic proportional pilot valve for downstream, and a downstream fixed throttle for downstream that is upstream. A downstream upstream fixed throttle that generates a differential pressure between the generated pilot flow and the downstream is interposed, and the downstream pressure of the downstream upstream fixed throttle is introduced as a pilot pressure into the pilot chamber of the lower control valve. The upstream pressure of the descending upstream fixed throttle is introduced into the exhaust chamber facing the pilot chamber, so that the rising or falling command pattern Renoid drive signal,
An opening command means for outputting to each of the electromagnetic proportional pilot valves as an open loop control signal is provided, and an oil temperature detecting means for detecting the temperature of hydraulic oil is installed in the hydraulic circuit. Based on the temperature signal from the temperature detecting means, a rising signal correction unit that outputs a solenoid drive signal in which the valve flow rate when the cage is raised and the volumetric efficiency of the hydraulic pump is compensated, and a cage descent signal when the cage is lowered A hydraulic elevator valve device, comprising: a descending signal correction unit that outputs a solenoid drive signal in which the valve flow rate is compensated.