JPH04277180A - Fluid pressure elevator - Google Patents

Abstract

PURPOSE:To decrease the capacity of a power source installation by reducing the drive power of a fluid pressure elevator, and to decrease the installation space by miniaturizing a fluid pressure control device, thereby effectively using the space of a building. CONSTITUTION:There are provided a fluid pressure cylinder 1 for driving a cage 7, an energy storage device 20 for storing energy having a value which can substantially balance the value of energy which is obtained when the load is one-half of a rated load of the elevator, and a fluid pressure control device 10 for shifting working fluid between the fluid pressure cylinder 1 and the energy storage device 20 while controlling the flow rate thereof. The fluid pressure energy of an fluid pressure elevator is boosted and stored in the energy storage device 20, and the pressure fluid is shifted between the fluid pressure cylinder 1 and the energy storage device 20 by the fluid pressure control device 10, thereby to control the elevation of a cage 7.

Description

[Detailed description of the invention]

0001

[Industrial Application] The present invention increases or decreases the speed of a car driven directly or indirectly by a hydraulic cylinder by controlling the flow rate of pressure fluid supplied to or discharged from the hydraulic cylinder. This invention relates to a type of hydraulic elevator.

0002

[Prior Art] When raising a car, a fluid pressure pump is used to generate enough fluid pressure to support the weight of the car including its load, and the flow rate of high-pressure fluid is controlled directly by a flow control valve or by the pump. The car is raised by supplying it to a fluid pressure cylinder while controlling the rotation speed by changing it. When lowering the car, the high-pressure fluid is discharged from a fluid pressure cylinder while being controlled directly by a flow control valve or by changing the rotational speed of a pump to lower the car.

[0003] This type of fluid pressure elevator using an accumulator is disclosed in, for example, Japanese Patent Laid-Open No. 63-30617.
There is one described in Publication No. 8.

0004

[Problems to be Solved by the Invention] When raising a car, the fluid pressure generated by the pump is the entire weight of the car including the load, and the energy required to drive the hydraulic pump is large. Therefore, the required power supply equipment or drive device becomes large. When lowering the car, the positional energy of the car is directly converted into heat energy by a control valve or motor and discarded. This may lead to an increase in the temperature of the fluid. That is, the energy supplied during upward movement is converted into heat and discarded during downward movement, resulting in a large energy loss.

An object of the present invention is to provide a fluid pressure elevator that can improve energy efficiency and reduce driving power when driving the fluid pressure elevator.

Another object of the present invention is to provide a hydraulic elevator whose power supply equipment or drive device can be made smaller and its installation area can be reduced.

[0007]

[Means for Solving the Problem] The above object is to control the flow rate of fluid supplied to or discharged from a fluid pressure cylinder by a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve, thereby increasing the speed of a car. This is achieved by providing an energy storage means coupled to the fluid pressure cylinder via the fluid pressure control means and storing fluid pressure energy for supplying to the fluid pressure cylinder in the hydraulic elevator for controlling the fluid pressure.

[0008] Furthermore, in the fluid pressure elevator, the speed of the car is controlled by controlling the flow rate of fluid supplied to or discharged from the fluid pressure cylinder by a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve. A pressure increasing means that is placed in parallel with the fluid pressure cylinder and stores gas on the high pressure side is provided, the pressure increasing means and the fluid pressure cylinder are coupled via the fluid pressure control means, and the fluid pressure is increased by the fluid pressure control means. This is achieved by reciprocating fluid between the cylinder and the pressure increasing means.

[0009]Furthermore, the car and the hydraulic cylinder are connected via a rope, and the car is raised by contracting the hydraulic cylinder, and lowered by the expansion of the hydraulic cylinder. In the pressure elevator, the fluid pressure cylinder and an accumulator storing gas on the high pressure side are placed side by side, and both are coupled via a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve, and the fluid pressure control means This is accomplished by reciprocating fluid between the hydraulic cylinder and the accumulator.

[0010]Furthermore, in the fluid pressure elevator, the speed of the car is controlled by controlling the flow rate of fluid supplied to or discharged from the fluid pressure cylinder by a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve. This is achieved by providing energy storage means coupled to the hydraulic cylinder via the hydraulic pressure control means, configured integrally with the hydraulic cylinder, and storing hydraulic energy for supplying to the hydraulic cylinder. Ru.

[0011]

[Function] Energy equivalent to the sum of the car's own weight and the rated load can be stored as fluid pressure in the energy storage means in advance, and when the fluid pressure elevator is actually driven, the energy is stored in the fluid pressure cylinder and the energy storage means. The hydraulic elevator is driven by supplying or absorbing energy corresponding to the energy difference between the hydraulic pump and the hydraulic pump. As a result, the energy required to drive the hydraulic elevator is reduced, and the required power is reduced, so that the power supply equipment and drive device can be made smaller, and the installation area can be reduced.

0012

[Embodiment] An embodiment of the present invention is shown in FIG. The fluid pressure elevator according to the present invention includes a car 7, a fluid pressure cylinder 1
, a fluid pressure control device 10 and an energy storage device 20. The car 7 is guided by rails 8 and supported by a hydraulic cylinder 1 via a rope 6 and a pulley 4. The fluid pressure cylinder 1 is composed of a cylinder 2 and a plunger 3 having a pulley 4 at the top thereof, and the plunger 3 expands and contracts by supplying and discharging working fluid to the cylinder 2. The fluid pressure control device 10 includes a fluid pressure pump 12 that can be rotated in forward and reverse directions, a motor 11, and control valves 13 and 14, and controls the flow of fluid between the fluid pressure cylinder 1 and the energy storage device 20. The energy storage device 20 includes a cylinder 21 and a stopper 2.
6 and a high-pressure gas tank 23, which converts the pressure energy of fluid, which is the working medium, into gas pressure energy and stores it. When the plunger 3 of the hydraulic cylinder 1 is at the lowest position, the working fluid is injected so that the piston 24 of the energy storage device 20 is at the highest position, and the car load is half of the rated load and half of the rated stroke. During a stroke, the gas chamber 25 and the gas tank 23 are filled with gas so that the pressure in the fluid pressure cylinder 1 and the pressure in the fluid chamber 24 of the cylinder 21 are approximately balanced.

The weight of the car is WC, the load of the car is WL, the weight of the pulley and plunger is Wj, the cross-sectional area of the plunger is Aj, the pressure of the fluid pressure cylinder is pj, and the fluid pressure of the cylinder of the energy storage device ( The pressure of the fluid chamber 24) is po, the gas pressure (pressure of the gas chamber 25) is pa, the variable volume of the fluid chamber 2c of the fluid pressure cylinder 1 is Vj, and the maximum volume of the fluid chamber 24 of the cylinder 21 is Vo (Vj<Vo ), the flow of fluid from the energy storage device 20 to the fluid pressure cylinder 1 is Qp, and the power supplied from the motor 11 to the fluid pressure pump 12 at this time is Lm. The speeds of the plunger 3 and the piston 22 are vj and va, and the pressure receiving areas of the piston 22 on the fluid side and gas side are Ao and Aa. If the structure of the fluid pressure elevator is indirect as shown in the figure, pj=(2・(WC+WL)+Wj)/AjLm=Qp
・(pj-po) Qp=Aj・vj=Ao・va Ao・po=Aa・pa Also, when the car is at approximately half of its rated stroke, the pressure in the fluid chamber is po0≒(2・WC+WL+Wj)/ Aj (the amount of gas sealed is not exact, but a rough amount is sufficient). In addition, it is sufficient that the amount of working fluid is slightly more than twice the fluctuating volume of the fluid pressure cylinder (Vj + Vo),
It does not require a large tank like conventional ones. Furthermore, since the pressure in the fluid chamber 24 is increased and stored in the gas chamber 25, the size of the energy storage device 20 is also reduced, making it much smaller than a conventional fluid pressure power unit.

Since the hydraulic elevator according to the present invention has the above-described structure, it operates as follows. First, when the car 7 rises, the control valve 14 is opened to communicate the fluid chamber 24 of the cylinder 21 to the fluid pressure pump, and the fluid pressure pump 12 is driven to supply high pressure fluid to the fluid pressure cylinder 1 via the control valve 13.
and push the car up through the rope. Speed control of the car 7 is performed by controlling the speed of a motor 11 that drives a fluid pressure pump 12.

Next, when the car 7 descends, the control valve 1
3 to open the high pressure fluid in the fluid pressure cylinder 1 to the fluid pressure pump 12, drive the fluid pressure pump 12, and open the control valve 14.
The high pressure fluid is supplied to the fluid chamber 24 of the energy storage device 20 through the
Then, the car 7 is lowered using its own weight. The speed control of the car 7 is executed by controlling the rotation speed of the fluid pressure pump 12 with the motor 13 in the same way as when raising the car.

The hydraulic elevator according to the present invention is adjusted as follows. After the elevator is assembled, the hydraulic cylinder 1 and the energy storage device 20 are supplied with working fluid at low pressure. Car 7 due to low fluid pressure
unable to push up its own weight. However, the hydraulic cylinder 1 is filled with working fluid. Furthermore, since the energy storage device 20 has no force to push the piston 22 (no gas is sealed), even if the fluid pressure is low, the piston 22 is pushed up and the fluid flows into the fluid chamber 24, which is filled with working fluid. The fluid chambers 24 of the fluid pressure cylinder 1, the fluid pressure control device 10, and the energy storage device 20 are now filled with working fluid. After that, working gas is filled into the gas tank 23 at a required pressure.

FIG. 2 is a diagram illustrating the state of supply and discharge of energy accompanying the operation of the elevator, that is, the relationship between the stroke of the car and fluid pressure. Elevators have strokes from 0 to full stroke, and pressure from minimum (no load) to maximum (
(full load) range. The pressure in the fluid chamber 24 of the energy storage device 20 is represented by a solid line because the volume of the gas chamber changes depending on the stroke. This gradient depends on the volume of the gas tank 23; the larger the volume, the smaller the gradient, and the smaller the volume, the larger the gradient. A certain load condition (
When the car makes a full stroke with the pressure of the fluid pressure cylinder = pj), the following energy is supplied and discharged to raise and lower the car.

In the case of ascending: The car 7 moves from A to C via B. At this time, the pressure in the fluid chamber 24 of the cylinder 21 changes from A' to C' via B. In other words, as the car 7 rises, the pressure AB changes from the pressure A'BC' line.
Move fluid to line C. Therefore, this ABC line and A'B
The energy corresponding to the area surrounded by C' line is the motor 1.
1 and the pump 12. This energy is Q
P・(pj-po), and the motor 11 has an area ABA'
and supplies the area BCC'.

In the case of descent: The car 7 moves from C to A via B. At this time, the pressure in the fluid chamber 24 of the cylinder 21 changes from C' to A' via B. In other words, as the car 7 descends, the pressure CB changes from the pressure C'BA' line.
Move fluid to line A. Therefore, this CBA line and C'B
The energy corresponding to the area surrounded by A' line is motor 1.
1 and the pump 12. This energy is Q
P・(pj-po), and the motor 11 has an area BCC'
and supplies area ABA'.

Comparing this with the conventional case, when the car 7 moves along the line ABC, the motor 11 uses the fluid pressure pump 12 to increase the fluid pressure from atmospheric pressure to the load pressure and sends it to the fluid pressure cylinder 1. supply That is, area ABC
Supply energy equivalent to DO. In the case of descent, when the car 7 moves along the CBA line, the working fluid in the hydraulic cylinder 1 is lowered from the load pressure to atmospheric pressure by the flow control valve (or by the motor 11 and the fluid pressure pump 12) and discharged into the tank. . That is, it absorbs energy corresponding to the area ABCDO.

The amount of energy supplied at this time determines the power of the motor, that is, the size of the power supply equipment, and the amount of energy absorbed determines the amount of heat generated. Therefore, it can be seen that the smaller the amount of energy supplied or absorbed in driving the elevator, the more convenient it is. Conventionally, it was necessary to supply and absorb energy between the load pressure and atmospheric pressure, and the amount was large, but in the present invention, the energy storage device 20 stores energy approximately equivalent to half of the rated load. The amount decreases dramatically. Therefore, if the present invention is compared with the conventional technology, it is clear that the present invention is superior.

FIG. 3 shows another embodiment of the present invention, which differs from the embodiment of FIG. 1 in the structure of the fluid pressure cylinder that is the driving device and the transmission path of the driving force. Fluid pressure cylinder 1
is composed of a cylinder 2, a piston 3 and a stopper 2a,
While the embodiment shown in FIG. 1 is a push-up type fluid pressure cylinder, this embodiment is a tension type fluid pressure cylinder. A pulley 4 is provided on the long part of the piston 3, and a pulley 5 is also provided in the hoistway to ensure stability. The rope 6, which is a driving force transmission medium, drives the car 7 via these pulleys. The car 7, the fluid pressure control device 10, and the energy storage device 20 are the same as in the previous embodiment. This embodiment is a tension-type fluid pressure cylinder, and there is no buckling of the plunger, which was a problem with the fluid pressure cylinders of the previous embodiments, and the fluid pressure cylinder 1 can be made compact. The pressure control device 10 can also be made smaller. In other words, it is possible to further reduce the size than the previous embodiment. Since the operation and the like are the same as those in the previous embodiment, the explanation will be omitted. Note that the same symbols as in the previous embodiment represent the same parts.

FIG. 4 shows an embodiment in which the energy storage device 20 of the embodiment shown in FIG. 3 is replaced with an accumulator 27.
This is possible because the hydraulic cylinder of the embodiment is small. The other structures, operations, and effects are the same as before, so their explanations will be omitted. Note that the same symbols as in the previous embodiment represent the same parts.

FIG. 5 shows yet another embodiment in which an energy storage device and a hydraulic cylinder are integrated. That is, the fluid pressure cylinder 1 is made into a double cylinder, and the piston 3 is slidably inserted into the inner cylinder 2, so that it functions as a fluid pressure cylinder as in the previous embodiment. The outer cylinder 2b acts as an accumulator of the energy storage device and stores energy. Therefore, the control valve 14 is in communication with the fluid chamber 2d of the outer cylinder, and the control valves 13, 1 are connected to the fluid chamber 2c of the inner cylinder 2.
4 and fluid pressure pump 12 to temporarily store the fluid pressure energy flowing through the pump 12 .

FIG. 6 is a diagram showing another embodiment of the present invention.
The fluid pressure cylinder 1 is composed of a cylinder 2 and a plunger 3 having a pulley 4 at the top thereof, and the plunger 3 expands and contracts by supplying and discharging working fluid to the cylinder 2. Further, the fluid pressure cylinder 1 is made into a double cylinder, and a piston 3 is slidably inserted into the inner cylinder 2, so that it functions as a fluid pressure cylinder. The outer energy storage device 20 functions as an accumulator by separating the fluid chamber 2d and the gas chamber 2f with a free piston 2e, and stores fluid pressure energy. The control valve 14 therefore communicates with the fluid chamber 2d of the outer energy storage device 20 and the inner cylinder 2d.
The fluid pressure energy flowing from the fluid chamber 2c through the control valves 13, 14 and the fluid pressure pump 12 is temporarily stored. The fluid pressure control device 10 includes a fluid pressure pump 12 that can be rotated in forward and reverse directions.
and a motor 11 and control valves 13 and 14 to control the flow of fluid between the hydraulic cylinder 1 and the energy storage device 20.

The hydraulic elevator in this embodiment is adjusted as follows. After the elevator is assembled, the hydraulic cylinder 1 and the energy storage device 20 are supplied with working fluid at low pressure. Since the fluid pressure is low, the weight of the car 7 cannot be pushed up. However, the hydraulic cylinder 1 is filled with working fluid. Also, since the energy storage device 20 does not have the force to push the free piston 2e (
Even if the fluid pressure is low (no gas is sealed), the free piston 2e is pushed up and the fluid flows into the fluid chamber 2d, which is filled with working fluid. The fluid chambers 2d of the fluid pressure cylinder 1, the fluid pressure control device 10, and the energy storage device 20 are now filled with the working fluid. After that, working gas is filled into the gas chamber 2f at a required pressure.

[0027] With the above structure, the required power can be reduced, so that the power supply equipment and the drive device can be made smaller, and the installation area of the drive device can also be made smaller.

FIG. 7 shows another embodiment of the hydraulic cylinder 1 of FIG. 6, in which the free piston 2e in the outer cylinder 21
is removed. When a gas and a fluid are brought into contact with each other and pressurized, a phenomenon occurs in which the gas becomes bubbles and mixes into the fluid. However, if there is no problem with the mixed amount, the number of parts can be reduced and the free piston 2e and cylinder 21
Work such as processing the inner surface is not required, making production easier.

FIG. 8 shows an embodiment of the fluid pressure control device 10 and a fluid pressure circuit of a precision car position correction device. The fluid pressure control device 10 includes a motor 11, a fluid pressure pump 12, main switching valves 31, 32, a pilot switching valve 33, shuttle valves 34, 35, a relief valve 36, a suction valve 37, and a tank 38. The flow path 15a communicates with the hydraulic cylinder 1, and the flow path 15b communicates with the energy storage device 20. Hydraulic cylinder 1 and energy storage device 2
0 means flow paths 15a, 15b, main switching valves 31, 32,
and are coupled via a fluid pressure pump 12. When driving the elevator, when the pilot switching valve 33 is energized, the high pressure side of the flow paths 15a and 15b becomes the pilot fluid pressure via the shuttle valve 34, and the main control valves 31 and 32 are operated to switch the flow paths 15a and 15b. and the fluid pressure pump 12. The fluid pressure pump 12 is connected to the motor 11
When the car 7 is driven in the upward or downward direction, the pressure fluid flows from the flow path 15b to 15a or in the opposite direction, causing the car 7 to rise or fall. When the pilot switching valve 33 is deenergized after the elevator stops, the main switching valves 31 and 32 return to their original positions and maintain the car 7 at its stopped position. The shuttle valve 35 and the relief valve 36 are connected to the flow path 15c.
, 15d are emergency valves that prevent abnormally high pressure. Conversely, the suction valve 37 prevents the flow paths 15c, 15d from becoming vacuum and damaging the hydraulic pump.

The precision position correction device 40 is composed of a motor 41, a pump 42, an accumulator 43, a flow control valve 44, a relief valve 45, a filter 46, and a tank 47. The flow control valve 44 is connected to the flow path 15a. and,
When the load on the car 7 changes and the car sinks or floats up, pressure fluid is supplied to or discharged from the hydraulic cylinder 1 to correct the position of the car 7 with high precision. That is, high-pressure fluid is stored in an accumulator 43 using the pump 42, and when the car 7 sinks, the pressure fluid in the accumulator 43 is supplied to the fluid pressure cylinder 1 using the flow control valve 44 to quickly correct the position of the car 7. . Conversely, when the car 7 floats up, the pressure fluid in the fluid pressure cylinder 1 is discharged to the tank 47 by the flow control valve, and the position of the car 7 is quickly corrected.

[0031]

[Effects of the Invention] According to the present invention, the driving power of the fluid pressure control device that drives the car can be significantly reduced, and furthermore,
Since the amount of working fluid is reduced, the fluid control device can be downsized. This not only makes it possible to downsize the power supply equipment, but also
The installation area of the elevator can be reduced, which means that the efficiency of building use can be increased.

[0032]

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of a hydraulic elevator according to the present invention.

FIG. 2 is a stroke-pressure diagram accompanying elevator operation.

FIG. 3 is a diagram showing another embodiment of the hydraulic elevator of the present invention.

4 shows another embodiment of the energy storage device of the embodiment shown in FIG. 2; FIG.

FIG. 5 is a diagram showing still another embodiment of the hydraulic elevator of the present invention.

FIG. 6 is a structural diagram of a hydraulic elevator showing another embodiment of the present invention.

FIG. 7 is a structural diagram of a hydraulic cylinder with an energy storage device;

FIG. 8 is a diagram showing an embodiment of a fluid pressure circuit of a fluid pressure control device for a fluid pressure elevator according to the present invention.

[Explanation of symbols]

1: Fluid pressure cylinder
13, 14: Control valve 2: Cylinder
15a, 15b: Channel 3: Plunger or piston 20: Energy storage device 4, 5: Pulley
21: Cylinder 6: Rope
22: Piston 7: Car 23
:Gas tank 8:Rail
24: Fluid chamber 10: Fluid pressure control device 25: Gas chamber 11: Motor 2
6: Stopper 12: Pump
27: Accumulator 31, 32: Main switching valve 40:
Precision position correction device 33: Pilot switching valve 41: Motor 34, 35: Shuttle valve
42: Fluid pressure pump 36: Relief valve
43: Accumulator 37 suction valve
44: Flow rate control valve 38, 47: Tank
45: Relief valve 46: Filter

Claims (9)

[Claims] 1. A fluid pressure elevator that controls the speed of a car by controlling the flow rate of fluid supplied to or discharged from a fluid pressure cylinder by a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve. A hydraulic elevator characterized in that it comprises an energy storage means coupled to the fluid pressure cylinder via the fluid pressure control means and storing fluid pressure energy for supplying to the fluid pressure cylinder. 2. The hydraulic elevator according to claim 1, wherein the energy storage means has two pressure receiving surfaces, one pressure receiving surface being acted upon by working fluid and the other pressure receiving surface being acted upon by gas. A fluid pressure elevator characterized by having a pressure intensifier structure. 3. In the fluid pressure elevator according to claim 2, when the car's own weight is WC and the car's load is WL, when the car is at approximately the center of its ascending and descending stroke, the pressure intensifier A fluid pressure elevator characterized in that the pressure intensifier is filled with gas so that the working load corresponds to (WC+WL/2). 4. The hydraulic elevator according to claim 2, wherein the volume of the chamber on which the high-pressure fluid of the pressure intensifier acts is larger than the volume of fluid flowing in and out of the fluid pressure cylinder, and the stroke of the piston of the pressure intensifier is A fluid pressure elevator characterized by being provided with a stopper that limits the 5. A fluid pressure elevator in which the speed of the car is controlled by controlling the flow rate of fluid supplied to or discharged from the fluid pressure cylinder by a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve. A pressure increasing means that is placed in parallel with the fluid pressure cylinder and stores gas on the high pressure side is provided, the pressure increasing means and the fluid pressure cylinder are coupled via the fluid pressure control means, and the fluid pressure is increased by the fluid pressure control means. A fluid pressure elevator characterized in that fluid is reciprocated between a cylinder and the pressure increasing means. 6. A hydraulic fluid having a structure in which a car and a hydraulic cylinder are connected via a rope, the car is raised by contraction of the hydraulic cylinder, and the car is lowered by extension of the hydraulic cylinder. In the pressure elevator, the fluid pressure cylinder and an accumulator storing gas on the high pressure side are placed side by side, and both are coupled via a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve, and the fluid pressure control means A fluid pressure elevator characterized in that fluid is reciprocated between the fluid pressure cylinder and the accumulator. 7. The hydraulic elevator according to claim 6, wherein the accumulator has two pressure receiving surfaces, one of which receives fluid pressure from the fluid pressure pump, and the other narrower pressure receiving surface receives gas. A fluid pressure elevator characterized by having a structure in which pressure acts, increases fluid pressure, and stores the energy in gas. 8. A fluid pressure elevator in which the speed of a car is controlled by controlling the flow rate of fluid supplied to or discharged from a fluid pressure cylinder by a fluid pressure control means including a fluid pressure pump and a fluid pressure control valve. Energy storage means is provided which is connected to the fluid pressure cylinder via the fluid pressure control means, is configured integrally with the fluid pressure cylinder, and stores fluid pressure energy to be supplied to the fluid pressure cylinder. A hydraulic elevator. 9. The fluid pressure elevator according to claim 8, wherein the fluid pressure cylinder constitutes a double cylinder fluid pressure cylinder with another cylinder provided to cover the outer periphery, and the outer cylinder is used for energy storage. A fluid pressure elevator characterized in that it is used as a means.