JP2010030722A - Hydraulic elevator device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To add a closing function used when a lowering speed exceeds to the pressure holding valve of a hydraulic elevator device inexpensively by a simple configuration. <P>SOLUTION: In this hydraulic elevator device having the pressure holding valve 11 in a main circuit between a hydraulic power unit 7 and a hydraulic jack 3, a solenoid valve 21 is installed in a discharge circuit 18 for discharging pressure oil from the back pressure chamber 17 of an opening/closing valve 15. Normally, the discharge circuit 18 is closed by the solenoid valve 21, and when a down instruction is given to a car 1, the discharge circuit 18 is opened to discharge the pressure oil from the back pressure chamber 17. The hydraulic elevator device is provided with a discharge circuit closing means for closing the discharge circuit 18 when necessary. The flow of the hydraulic oil flowing through the main circuit is detected by the discharge circuit closing means. When the flow equal to or more than a predetermined value is detected, the discharge circuit 18 is closed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hydraulic elevator apparatus in which a pressure holding valve is provided between a hydraulic power unit and a hydraulic jack.

  Conventionally, a hydraulic elevator apparatus has been provided with a fall prevention device to prevent a car from falling. In the case of a hydraulic elevator device, it is extremely unlikely that overspeed will occur due to a failure of the hydraulic system, or the car will fall due to oil leakage from hydraulic piping or joints. For this reason, the conventional hydraulic elevator apparatus is mainly applied with a device for preventing the car from dropping due to a rope breakage or the like, for example, a device called a slack rope type emergency stop. It was configured to make an emergency stop.

  However, in recent years, when the free arrangement of the elevator machine room, which is an advantage of the hydraulic elevator apparatus, is widely adopted, there are not many hydraulic pipes that are placed in a rusting and corrosive environment such as outdoors. Things are getting scattered. Even in such a case, the safety must be ensured by regular maintenance inspections. However, if hydraulic piping or its joints are significantly corroded and oil leaks from those parts, There was a possibility that the car could descend uncontrolled while the elevator doors were open.

  As a prior art for such a problem, for example, there is one described in Patent Document 1 below. In the thing of patent document 1, the pressure holding valve is installed in the hydraulic piping which connects a hydraulic power unit and a hydraulic jack. This pressure holding valve is intended to prevent the car from descending due to oil leakage from the hydraulic piping or the failure of the hydraulic control valve in the machine room, or to minimize the car's ups and downs when passengers get on and off. It is prepared for the purpose of keeping it down.

JP 11-322207 A

  In the hydraulic elevator system, as described in Patent Document 1, by installing a pressure holding valve in the vicinity of the hydraulic jack, it is possible to reduce the ups and downs of the car when getting on and off, and in the unlikely event that oil leaks from the hydraulic piping Even if this occurs, the car can be held at the stop position. However, since this pressure holding valve does not have an overspeed detection function, when the lowering speed of the car exceeds a predetermined value, the car cannot be decelerated and stopped urgently. For this reason, conventionally, a rupture valve, an emergency stop with a governor, etc. must be provided to prepare for hydraulic oil spills due to a hydraulic pipe rupture accident, etc., and the configuration becomes complicated and expensive. was there.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to add a closing function when the descending speed is exceeded to the pressure holding valve with a simple configuration and at a low cost. It is to provide a hydraulic elevator device that can be used.

  A hydraulic elevator apparatus according to the present invention includes a hydraulic jack for driving an elevator car, a hydraulic power unit connected to the hydraulic jack via a main circuit, and an on-off valve provided in the main circuit for opening and closing the main circuit. When raising the car, the pressure of the hydraulic oil supplied from the hydraulic power unit opens the on-off valve to send the hydraulic oil to the hydraulic jack, and when lowering the car, A hydraulic elevator device that opens the on-off valve by discharging the pressure oil from the back pressure chamber of the on-off valve and returns the hydraulic oil to the hydraulic power unit side, and discharges the pressure oil from the back pressure chamber. A solenoid valve that is provided in the circuit and normally closes the discharge circuit and opens the discharge circuit to discharge pressure oil from the back pressure chamber when the lowering command is issued to the car. Detecting the flow rate of the oil, when more than a predetermined value of the flow rate is detected, in which and an exhaust circuit closure means closing the discharge circuit.

  According to the present invention, a closing function when the descending speed is exceeded can be added to the pressure holding valve of the hydraulic elevator device with a simple configuration and at a low cost.

  In order to explain the present invention in more detail, it will be described with reference to the accompanying drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a hydraulic elevator apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a view for explaining the operation of the electromagnetic valve shown in FIG.
In FIG. 1, reference numeral 1 is a car that moves up and down in an elevator hoistway, 2 is a main rope that has one end connected to the car 1, and the other end connected to a fixed body of the hoistway, etc. It is a hydraulic jack that is erected in the road and drives the car 1 through the main rope 2.

  The main part of the hydraulic jack 3 includes a cylinder 4, a plunger 5, and a sheave 6. For example, the sheave 6 is rotatably provided at the upper end portion of the plunger 5, and a part of the main rope 2 is wound around the rope groove at the outer peripheral portion. Then, the hydraulic oil supplied to the cylinder 4 is controlled by the hydraulic power unit 7 or the like, so that the plunger 5 (sheave 6) is moved up and down to move (elevate and lower) the car 1 through the movement of the main rope 2. Further, while the car 1 stops at the landing and the passenger gets on and off the car 1, the car position is held by the check valve (a control valve 10 described later) in the hydraulic power unit 7.

  The hydraulic power unit 7 is connected to the hydraulic jack 3 via a main circuit, and its main part is constituted by a pump 8, a motor 9, a control valve 10, and the like. The pump 8 is for supplying hydraulic oil to the hydraulic jack 3 and is driven by the motor 9. The control valve 10 adjusts the flow rate of hydraulic oil supplied from the hydraulic power unit 7.

  Reference numeral 11 denotes a pressure holding valve provided between the hydraulic power unit 7 and the hydraulic jack 3, that is, in the main circuit. A hydraulic pipe 12 is connected between the pressure holding valve 11 and the hydraulic power unit 7, and a hydraulic pipe 13 is connected between the pressure holding valve 11 and the hydraulic jack 3. That is, the hydraulic pipe 12 constitutes a main circuit closer to the hydraulic power unit 7 than the pressure holding valve 11, and the hydraulic pipe 13 constitutes a main circuit closer to the hydraulic jack 3 than the pressure holding valve 11. A stop valve 14 is provided in the hydraulic pipe 12 near the hydraulic power unit 7.

As described above, the pressure holding valve 11 is used to prevent the car 1 from descending due to oil leakage from the hydraulic piping 12 or failure of the hydraulic control valve in the machine room, or when passengers get on and off. It is provided for the purpose of minimizing the ups and downs of the car 1. Further, the pressure holding valve 11 is disposed in the vicinity of the hydraulic jack 3 for the above purpose.
Hereinafter, the configuration of the pressure holding valve 11 and the configuration for adding a closing function when the descending speed is exceeded to the pressure holding valve 11 will be specifically described.

  An open / close valve 15 is provided in the pressure holding valve 11 and has a function of opening and closing the main circuit. Specifically, in a state where the on-off valve 15 is fully closed, the hydraulic oil passage between the hydraulic pipe 12 and the hydraulic pipe 13 is shut off, and the on-off valve 15 opens (moves upward in FIG. 1), The hydraulic fluid is configured to pass between the hydraulic piping 12 and the hydraulic piping 13.

Reference numeral 17 denotes a back pressure chamber of the on-off valve 15. A discharge circuit 18 is connected to the hydraulic pipe 12, and a connection circuit 19 is connected to the hydraulic pipe 13.
The discharge circuit 18 is provided for discharging hydraulic oil from the back pressure chamber 17, and a check valve 20, a solenoid valve 21, and a differential pressure detection valve 22 are provided in series. The check valve 20 has a function of preventing hydraulic oil from flowing into the back pressure chamber 17 from the hydraulic pipe 12. The solenoid valve 21 always closes the discharge circuit 18 to cut off the flow of hydraulic oil from the back pressure chamber 17 to the hydraulic pipe 12 and opens the discharge circuit 18 when necessary to operate the back pressure chamber 17. A flow path for discharging oil to the hydraulic pipe 12 is formed. Specifically, as shown in FIG. 2, the solenoid valve 21 is coil-excited when a lowering command for the car 1 is output from a control panel (not shown), opens the discharge circuit 18, and the back pressure chamber 17. Is discharged to the hydraulic pipe 12.

  The differential pressure detection valve 22 constitutes a main part of the discharge circuit closing means together with the hydraulic power unit side pilot circuit 23 and the hydraulic jack side pilot circuit 24. That is, the differential pressure detection valve 22 and the like have a configuration for detecting the flow rate of hydraulic oil flowing in the main circuit and closing the discharge circuit 18 when a flow rate equal to or higher than a predetermined value is detected.

  Here, the discharge circuit closing means in the present embodiment is configured to detect the flow rate of the hydraulic oil flowing through the main circuit based on the pressure difference of the hydraulic oil generated before and after the pressure holding valve 11. In the pressure holding valve 11, it is known that a pressure difference corresponding to the flow rate of the hydraulic oil is generated in the hydraulic oil flow (flow from the hydraulic jack 3 to the hydraulic power unit 7) when the car 1 is lowered. . That is, when the flow rate of hydraulic oil is large, the pressure difference increases (proportional to the square of the flow rate), and when the flow rate is small, the pressure difference also decreases. The discharge circuit closing means detects the flow rate of the hydraulic oil flowing in the main circuit using this property.

  Specifically, the differential pressure detection valve 22 has a function of opening and closing the discharge circuit 18 and is normally held in a state where the discharge circuit 18 is opened by the adjustment spring 25. The hydraulic power unit side pilot circuit 23 has one side connected to the hydraulic pipe 12 (in the configuration shown in FIG. 1, the hydraulic pipe 12 via a part of the discharge circuit 18), and the other side to the differential pressure detection valve 22. On the other hand, the pressure is applied in the direction in which the discharge circuit 18 is opened. Further, the hydraulic jack side pilot circuit 24 is connected to the hydraulic pipe 13 on one side (in the configuration shown in FIG. 1, the hydraulic jack side pilot circuit 24 is connected to the back pressure chamber 17, thereby connecting the back pressure chamber 17 and the connection circuit 19. And the other side has a configuration in which pressure is applied to the differential pressure detection valve 22 in a direction in which the discharge circuit 18 is closed.

  When the flow rate of the hydraulic fluid flowing through the main circuit increases, the differential pressure detection valve 22 increases the differential pressure across the pressure holding valve 11 (pressure difference between the hydraulic power unit side pilot circuit 23 and the hydraulic jack side pilot circuit 24). When this differential pressure reaches a predetermined set value, the discharge circuit 18 is closed, and the flow of hydraulic oil from the back pressure chamber 17 to the hydraulic pipe 12 is shut off.

When the elevator is in operation, the pressure difference fluctuates due to a change in the viscosity of the hydraulic oil due to the oil temperature or the like. For this reason, regarding the arrangement, adjustment, and the like of the differential pressure detection valve 22, it is necessary to set in advance a point at which malfunction does not occur in consideration of fluctuations in the pressure difference.
The differential pressure detection valve 22 is adjusted so that, for example, when the car 1 descends at a speed 1.4 times or more the rated speed of the elevator, the pressure difference at that time is detected and the discharge circuit 18 is closed. Keep it. Such adjustment is performed by increasing or decreasing the initial opening amount of the differential pressure detection valve 22. During the adjustment, the initial deflection amount of the adjustment spring 25 is also set at the same time.

  1, 26 is a stop valve provided in the discharge circuit 18 in parallel with the electromagnetic valve 21, 27 is a fixed throttle provided in the connection circuit 19, 28 is provided in the back pressure chamber 17, and the on-off valve 15 is always connected. This is a push spring that urges one side (downward in FIG. 1).

Next, the operation of the hydraulic elevator apparatus having the above configuration will be specifically described.
When a raising command is output from the control panel to raise the car 1, the motor 9 of the hydraulic power unit 7 is driven, and hydraulic oil is supplied from the pump 8 to the hydraulic pipe 12. When the hydraulic oil is supplied from the pump 8, the pressure of the hydraulic oil in the main chamber 16 rises, and the opening / closing valve 15 of the pressure holding valve 11 causes the pressure of the hydraulic oil in the back pressure chamber 17 and the pressure spring 28. It is pushed up against the urging force. Then, the hydraulic oil is supplied from the hydraulic pipe 12 side to the hydraulic jack 3, whereby the plunger 5 is pushed up and the car 1 is raised.

When the car 1 is raised, the solenoid valve 21 is not coil-excited. For this reason, the hydraulic oil in the back pressure chamber 17 cannot return to the hydraulic pipe 12 via the discharge circuit 18. That is, a part of the hydraulic oil in the back pressure chamber 17 escapes to the hydraulic pipe 13 through the fixed throttle 27 when the on-off valve 15 is pushed up.
Further, when the car 1 is raised, the pump pressure from the hydraulic power unit 7 side becomes higher than the jack pressure, so that the on-off valve 15 is automatically opened. Therefore, the ascending operation is possible regardless of the open / closed state of the discharge circuit 18. Further, in the hydraulic elevator device, the hydraulic oil flow rate does not exceed the rotational speed of the pump 8, and therefore the ascending speed of the car 1 does not increase to the critical speed.

  On the other hand, when a lowering command is output from the control panel in order to lower the car 1, the electromagnetic valve 21 is coil-excited, and a flow path of hydraulic oil from the back pressure chamber 17 to the hydraulic pipe 12 is formed. That is, when the electromagnetic valve 21 is opened, the hydraulic oil in the back pressure chamber 17 flows into the hydraulic pipe 12 via the discharge circuit 18. For this reason, the pressure in the back pressure chamber 17 falls, and the force for opening the on-off valve 15 is generated. As a result, the on-off valve 15 is opened, the control valve 10 controls the flow rate of the working oil to be recirculated from the hydraulic jack 3, and the car 1 is lowered.

  When the hydraulic oil flow rate is exceeded due to some reason, for example, a hydraulic oil spill accident or a valve failure when the car 1 is lowered, the hydraulic oil flow rate (pressure difference between the front and rear valves 15) is predetermined. When the value is exceeded, the differential pressure detection valve 22 is closed. As a result, the hydraulic oil in the back pressure chamber 17 loses escape, and the hydraulic oil in the hydraulic pipe 13 only flows into the back pressure chamber 17 through the fixed throttle 27. When the car 1 is lowered, the pressure on the hydraulic jack 3 side is higher than the pressure on the hydraulic power unit 7 side. For this reason, when the hydraulic oil on the hydraulic jack 3 side flows into the back pressure chamber 17, the on-off valve 15 is immediately closed, and the lowering of the car 1 is prevented.

  Note that once the differential pressure detection valve 22 is operated when the car 1 is lowered, the on-off valve 15 is closed, so that the pressure on the hydraulic pipe 12 side is held lower than the pressure on the hydraulic pipe 13 side (hydraulic pipe The pressure on the 12 side is almost zero). For this reason, in such a case, the differential pressure detection valve 22 does not automatically open, and the differential pressure detection valve 22 keeps the discharge circuit 18 closed unless it is manually opened.

  According to the first embodiment of the present invention, a closing function when the descending speed is exceeded can be added to the pressure holding valve 11 of the hydraulic elevator apparatus with a simple configuration and at a low cost.

  In other words, even when the hydraulic oil flow rate is exceeded due to an accident such as a hydraulic oil spill or a valve failure when the car 1 is descending, the on-off valve 15 is immediately closed and the car 1 can be prevented from descending. Moreover, the safety | security at the time of the raise of the cage | basket | car 1 and a stop can be ensured with the function which the pressure holding valve 11 had conventionally. For this reason, it is possible to ensure safety in various situations, such as when there is a deficiency in maintenance inspection, which is a human work, or when a power failure or valve failure occurs.

Embodiment 2. FIG.
FIG. 3 is a main part configuration diagram showing a hydraulic elevator apparatus according to Embodiment 2 of the present invention. In the first embodiment, the case where the flow rate of the hydraulic fluid flowing through the main circuit is detected based on the pressure difference of the hydraulic fluid generated before and after the pressure holding valve 11 by employing the differential pressure detection valve 22 and the like will be described. did. In contrast, in the present embodiment, a case will be described in which the flow rate of hydraulic oil flowing through the main circuit is directly detected as the discharge circuit closing means.

Specifically, the main part of the discharge circuit closing means in the present embodiment is constituted by a flow rate sensor 29 using ultrasonic waves and a control unit 30 (closing means).
Recently, high-quality flow sensors have been developed, and high-reliability and high-accuracy flow measurement is possible. For example, in the market, devices that can measure up to a unit level with an error of about 1% and a flow rate of about 0.3 m / s are commercially available. Therefore, even if such a flow rate sensor is used in a hydraulic elevator that is used in a flow velocity range of about 1 to 5 m / s during normal traveling, it is possible to detect the overspeed sufficiently. The flow rate sensor 29 is employed in consideration of the above-described circumstances and the like. For example, the flow rate sensor 29 is provided in the hydraulic piping 12 and detects the flow rate of the hydraulic oil flowing inside the hydraulic piping 12 from the outside of the hydraulic piping 12. It has a function.

Specifically, the flow sensor 29 transmits an ultrasonic wave having a predetermined frequency from a transmitting ultrasonic transducer 31 installed on the outer peripheral surface of the hydraulic pipe 12 and receives a reflected wave reflected by the inner wall of the hydraulic pipe 12. Is received by the ultrasonic transducer 32 for use.
When the ultrasonic wave generated by the ultrasonic vibrator 31 is received by the ultrasonic vibrator 32, a slight time difference is generated in the reflected wave according to the flow rate of the hydraulic oil flowing in the hydraulic pipe 12. . For this reason, the control unit 30 converts the time difference detected by the flow sensor 29 into a flow value, and outputs a command for closing the discharge circuit 18 when the flow value reaches a predetermined threshold value. FIG. 3 shows a configuration in which the discharge circuit 18 is closed by exciting the electromagnetic valve 21 as an example. That is, when the flow rate of the hydraulic oil equal to or greater than a predetermined value is detected by the flow sensor 29, the control unit 30 excites the electromagnetic valve 21 and blocks the hydraulic oil flow path from the back pressure chamber 17 to the hydraulic pipe 12. To do.

As described above, the lowering speed of the car 1 when operating the discharge circuit closing means is preferably within 1.4 times the rated lowering speed. However, in the case of a hydraulic elevator device, when an overspeed phenomenon occurs due to the outflow of hydraulic oil, the lowering speed of the car 1 often easily reaches a speed that is at least twice the rated lowering speed. For this reason, in the discharge circuit closing means having the above-described configuration, the discharge circuit closing means is operated when the car 1 reaches, for example, twice the rated lowering speed of the elevator in consideration of the risk of malfunction. The discharge circuit 18 may be adjusted to be closed.
Others have the same configuration and functions as in the first embodiment.

  According to the second embodiment of the present invention, the same effects as those of the first embodiment can be obtained even in the above configuration. Further, if the flow sensor 29 having the above-described configuration is employed, the flow rate of the hydraulic oil flowing through the hydraulic pipe 12 from the outside of the hydraulic pipe 12 can be detected. There is also an advantage that it can be done.

It is a block diagram which shows the hydraulic elevator apparatus in Embodiment 1 of this invention. It is a figure for demonstrating operation | movement of the solenoid valve shown in FIG. It is a principal part block diagram which shows the hydraulic elevator apparatus in Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Car 2 Main rope 3 Hydraulic jack 4 Cylinder 5 Plunger 6 Sheave 7 Hydraulic power unit 8 Pump 9 Motor 10 Control valve 11 Pressure holding valve 12, 13 Hydraulic piping 14, 26 Stop valve 15 Open / close valve 16 Main chamber 17 Back pressure chamber 18 Discharge Circuit 19 Connection circuit 20 Check valve 21 Solenoid valve 22 Differential pressure detection valve 23 Hydraulic power unit side pilot circuit 24 Hydraulic jack side pilot circuit 25 Adjustment spring 27 Fixed throttle 28 Push spring 29 Flow rate sensor 30 Control unit 31, 32 Ultrasonic vibrator

Claims (6)

A hydraulic jack to drive the elevator car;
A hydraulic power unit connected to the hydraulic jack via a main circuit;
A pressure holding valve provided in the main circuit and having an on-off valve for opening and closing the main circuit;
With
When raising the car, the pressure of hydraulic oil supplied from the hydraulic power unit opens the on-off valve to send hydraulic oil to the hydraulic jack, and when lowering the car, the back of the on-off valve A hydraulic elevator apparatus that opens the on-off valve to discharge hydraulic oil to the hydraulic power unit side by discharging pressure oil from a pressure chamber;
Provided in a discharge circuit for discharging pressure oil from the back pressure chamber, and normally closes the discharge circuit and opens the discharge circuit to discharge pressure oil from the back pressure chamber when a lowering command is issued to the car. A solenoid valve;
A discharge circuit closing means for detecting a flow rate of the hydraulic oil flowing through the main circuit and closing the discharge circuit when a flow rate of a predetermined value or more is detected;
A hydraulic elevator apparatus comprising:   The hydraulic elevator apparatus according to claim 1, wherein the discharge circuit closing means detects a flow rate of the hydraulic oil flowing through the main circuit based on a pressure difference between the hydraulic oil generated before and after the pressure holding valve. The discharge circuit closing means is
A differential pressure detection valve that opens and closes the discharge circuit;
A hydraulic power unit side pilot circuit that is connected to a main circuit on the hydraulic power unit side of the pressure holding valve and applies pressure to the differential pressure detection valve in a direction to open the discharge circuit;
A hydraulic jack-side pilot circuit that is connected to the main circuit on the hydraulic jack side of the pressure holding valve and applies pressure to the differential pressure detection valve in a direction to close the discharge circuit;
With
The differential pressure detection valve keeps the discharge circuit open at all times, and when the pressure difference between the hydraulic jack side pilot circuit and the hydraulic power unit side pilot circuit reaches a predetermined set value, the discharge pressure detection valve The hydraulic elevator apparatus according to claim 2, wherein the circuit is closed. A connection circuit connected between the main circuit on the hydraulic jack side of the pressure holding valve and the back pressure chamber of the pressure holding valve;
Further comprising
4. The hydraulic elevator apparatus according to claim 3, wherein the hydraulic jack-side pilot circuit is connected to a main circuit on the hydraulic jack side of the pressure holding valve via the back pressure chamber and the connection circuit. . The discharge circuit closing means is
A flow rate sensor for detecting the flow rate of hydraulic fluid flowing in the main circuit from the outside of the hydraulic piping constituting the main circuit;
Closing means for closing the discharge circuit when the flow rate of the hydraulic oil above a predetermined value is detected by the flow rate sensor;
The hydraulic elevator apparatus according to claim 1, further comprising:   6. The hydraulic elevator apparatus according to claim 5, wherein the closing means excites the electromagnetic valve to close the discharge circuit when the flow rate of the hydraulic oil equal to or higher than a predetermined value is detected by the flow rate sensor.

Images