JPH01308383A - Energy-saving type hydraulic elevator - Google Patents

Abstract

PURPOSE:To make motive power and equipment power both smaller by lowering a main elevator with its own weight at the time of down of this main elevator in the case where loadage of the main elevator is heavier than an adjusting weight, and forming it into such a structure as feeding a sub cylinder with hydraulic fluid in a main cylinder and thereby rotating a hydraulic pump and a motor. CONSTITUTION:When a main elevator is made to go up in the case where loadage of this main elevator 4 is heavier than an adjusting weight 13, a hydraulic pump 10 is driven and hydraulic fluid is fed to the inside of a main cylinder of the main elevator from the inside of a sub cylinder of a balance elevator 7. At the time of its down, the main elevator is lowered with its own weight, whereby a hydraulic pump-motor is rotated. Inversely, when the loadage of the main elevator is lighter than the adjusting weight and it goes up, the balance elevator is lowered with its own weight, hydraulic fluid in the sub cylinder is fed to the inside of the main cylinder, thereby rotating the hydraulic pump- motor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a hydraulic elevator, and particularly to one with improved energy efficiency during operation.

(Prior Art) In a conventional hydraulic elevator, a ram (15) having a cage (2) for loading people and/or cargo at the upper end is inserted into a hydraulic cylinder (16), as shown in FIG. 2, for example. A hydraulic pump (not shown) causes hydraulic oil (X) to flow into or out of the hydraulic cylinder (16) from an oil tank to raise or lower the cage (2), or a person as shown in FIG. and/or attach the upper end of the cargo loading cage (2) to one end of the wire (17) through a pulley (18) and attach a weight (19) to the other end so that the cage (2) can be raised. There is a structure in which the cage (2) is pulled upward by the weight of (19) and the load on the hydraulic pump is reduced by the pressure valve corresponding to the tension.

[Problem to be solved by the invention] However, in the hydraulic elevator shown in Fig. 2, the cage (2)
When the weight of the ram (15) is A, the weight of the ram (15) is 8, and the maximum loading weight is W, the power of the hydraulic pump drive motor, that is, the required power when raising the elevator at the speed of ■, is given by the following formula: expressed.

(A+B+W)xV (1) Since the entire load is applied as a load to the motor, a large-capacity motor is required, and the temperature rise of the hydraulic oil is also large.

Further, in the hydraulic elevator shown in FIG. 3, when the weight of the weight (19) is 7, the power required to raise the elevator at a speed of V is expressed by the following equation.

(A+B+W-Z)xV...(2) In this way, the load on the motor is smaller than in equation (1), and a relatively small capacity motor is sufficient, but the above weight is held by the building. Therefore, the structure of the building will be large-scale or require strong reinforcement.

In addition, when these hydraulic elevators are lowered, it is common to construct a circuit that uses the weight of the elevator to force the hydraulic oil in the cylinder to pass through a throttle valve, control the speed, and return it to the oil tank. The hydraulic elevator shown in FIG. 1 works effectively only when the weight (Z) of the weight is lighter than the total weight of the loaded weight, cage, and ram (fir(W+A+8)).

[Means to solve the problem]

In view of this, as a result of various studies, the present invention has developed an energy-saving hydraulic elevator that solves these problems.

That is, the present invention consists of a main elevator that raises and lowers a ram to which a cage for carrying people and/or cargo is attached by causing hydraulic oil to flow into or out of the main cylinder, and a balance elevator consisting of a ram to which a fixed weight is attached and a sub-cylinder. A communication path is formed that communicates the inside of each cylinder with each other via a hydraulic pump, and an adjustment weight with a weight of approximately 172 kg, which is the maximum load weight, is attached to the fixed weight to balance the hydraulic pressure in the communication path on the main elevator side. An emergency lowering valve is provided to reduce the pressure difference with the hydraulic pressure in the communication passage on the elevator side and discharge internal hydraulic oil to the communication passage on the main elevator side, and supply internal hydraulic oil to the communication passage on the balance elevator side. A hydraulic pump is provided to correct the relative position of the main cylinder and sub-cylinder, and when the main elevator's loaded weight is greater than the adjustment weight, the hydraulic pump installed in the communication path is driven to pump hydraulic fluid when the main elevator is raised. is sent from the auxiliary cylinder of the balance elevator to the main cylinder of the main elevator.In this case, when the main elevator is lowered, the main elevator is lowered by its own weight, so that the hydraulic oil in the main cylinder flows through the communication passage. The hydraulic pump and motor are rotated by the hydraulic oil sent and distributed in the sub-cylinder, and when the main elevator is raised when the main elevator's loaded weight is smaller than the adjustment weight, the balance elevator is lowered by its own weight. Due to the operation of the sub cylinder,
The hydraulic pump and motor are rotated by the hydraulic oil that circulates through the communication passage and sends the oil into the main cylinder.
On the other hand, when lowering the main elevator in this case, a hydraulic circuit is formed in the communication path to drive the hydraulic pump and send hydraulic oil from the main cylinder to the sub cylinder, and a device is also installed to control the drive motor of the hydraulic pump using an inverter. It is characterized by the fact that it has been provided.

[For production]

In this way, the main elevator's maximum loading type ffi (W>), which has a weight of approximately 172, is attached to the balance elevator's fixed weight by adjusting the hydraulic pressure in the communication passage on the main elevator side and the oil pressure in the communication passage on the balance elevator side. This is to reduce the pressure difference between the cylinders of both elevators because the load on the balance elevator side is approximately 172W higher when the main elevator is raised with no people and/or cargo loaded in the cage of the main elevator. The main elevator is pushed up with a pressure equivalent to about 172 W by communicating with the inside and lowering the balance elevator by its own weight, so in this case, a hydraulic pump is not required, that is, no electrical energy is required to drive the hydraulic pump. Moreover, since the hydraulic pump is rotated by the hydraulic oil flowing through the communication path at this time, it has the advantage that the motor acts as a generator and regenerates electric power to the inverter.By performing such regeneration control, this regeneration Electric power is stored in a capacitor in the DC circuit inside the inverter, and as this increases, the electric power is recovered as thermal energy by an external braking resistor unit, etc. for multi-purpose demand such as hot water supply and space heating, but it is also released outdoors. It has the advantage of being able to

On the other hand, in order to lower the main elevator in this state, the hydraulic oil in the main cylinder, which is under pressure due to the weight of the main elevator cage and the weight of the ram, is applied with a hydraulic pump to a pressure equivalent to the weight of approximately 172 W, and the hydraulic oil is transferred to the secondary balance elevator. send into the cylinder.

By operating in this manner, the balance elevator ascends at the same speed (V) as the descending speed of the main elevator. That is, the required power of the motor in this case is approximately as follows.

-1/2WXV----- (3) 5 Therefore, compared to the above equations (1) and (2), it has the advantage that it can be operated with a motor of very small capacity.

Conversely, if the main elevator is raised with the maximum loading weight (W>) added to the main elevator, the above is...
On the other hand, the addition on the main elevator side increases by about 1/2 W, so the hydraulic oil in the sub cylinder, which is under the pressure of the balance elevator's adjustment weight weight, fixed weight weight, and ram weight, is pumped by a hydraulic pump to a weight equivalent to about 172 W. Pressure is applied and sent into the main cylinder of the main elevator to raise the main elevator and simultaneously lower the balance elevator. In this case, the power required by the motor for driving the hydraulic pump is expressed as in equation (3), where V is the elevator's ascending/descending speed, resulting in great energy savings.

On the other hand, when lowering the main elevator in this state, by communicating the insides of the cylinders of both elevators and allowing the main elevator to descend under its own weight, the balance elevator can be raised at the same speed as the lowering speed of the elevator, so the hydraulic pump is used. It does not need to be driven, and has the advantage of being able to use regenerated power in the same way as above.

In this way, the weight of the adjustment weight of a balance elevator is generally about 172 kg, which is the maximum loading weight, but this weight depends on the actual usage conditions due to the pressure difference between the communication passage on the main elevator side and the communication passage on the balance elevator side. It should be set to the most effective value in terms of efficiency so that the overall value is small.

Since an emergency lowering valve is provided in the communication passage on the main elevator side, there is an advantage that the main elevator can be lowered regardless of the failure of the balance elevator or the hydraulic pump.

Since the rough correction hydraulic pump can supply leaked hydraulic oil into the auxiliary cylinder, it has the feature that the relative position of the balance elevator with respect to the main elevator can always be kept constant.

Furthermore, as shown in equation (3), the power of the motor is smaller than that of the conventional motor, so a small-capacity motor can be used, and the cost of electrical equipment can be reduced.

Furthermore, since the hydraulic fluid is received and transferred only within both cylinders, a very small oil tank is sufficient to store the hydraulic fluid, which is advantageous in terms of space, and because the hydraulic fluid generates little heat, the amount of oil can be reduced. Less is enough.

In addition, balance elevators can be installed in dead spaces in buildings, so they do not require new space.
Another feature is that it does not require a structure to support the weight of the building as in the past.

Since the power source of the Zaraani drive motor is controlled by an inverter, the poor riding comfort caused by the shock during normal elevator acceleration can be eliminated by speed control.
52784). Note that it is also possible to use a normal variable pump without an inverter.

〔Example〕

Next, one embodiment of the present invention will be described.

Fig. 1 shows an example of an energy-saving hydraulic elevator according to the present invention.The main cylinder (1) has a main ram (1) with a cage (2) for loading people and/or cargo attached to its upper end by allowing hydraulic oil to flow into or out of the main cylinder (1). The balance elevator (7) consists of a main elevator (4) that raises and lowers the balance elevator (7) and a sub-ram (3°) integrally equipped with a fixed weight (5) and a sub-cylinder (6). ), and a hydraulic pump (10) and a speed regulating valve (11) driven by a motor (9) with an inverter control device (not shown) installed in the communication path (8). )
A hydraulic circuit (12) consisting of (11°) etc. is provided, and an emergency lowering valve (20) consisting of a check valve is provided on the main elevator side of the communication path (8) to discharge hydraulic oil in an emergency.
In addition, on the balance elevator side of the communication passage (8), there is a correction hydraulic pump (14) that supplies hydraulic oil into the sub-cylinder (6).
).

The balance elevator (7) has a main elevator (4).
) Adjustment weight (1
3) was attached on the fixed weight (5).

Note that since the speed control valves [11] (11') each have a check valve, the stop position of each elevator can be completely compensated for.

The operation of the energy-saving hydraulic elevator having such a configuration will be explained next.

■If there are no people or loaded cargo in the main elevator cage, in this case the pressure on the balance elevator (7) side will be high by the load of the adjustment weight, but in order to raise the main elevator at this time, balance elevator (7) By lowering it by its own weight, the hydraulic oil flows through the communication passage (8), and the speed control valve (11") on the balance elevator (7) side
The communication passage (8) is narrowed down and the secondary cylinder (6) on the high pressure side
The main elevator (4) is raised by controlling the speed at which the hydraulic oil inside flows to the low-pressure side main cylinder (1). At this time, since the hydraulic pump (10) rotates at the same time, the motor (9) acts as a generator, and the rotational energy is regenerated as electric power to the inverter and stored or released.

Next, to lower the main elevator, use the main elevator (4).
The communication passage (8) is opened by the speed control valve (11) on the side, and the hydraulic pump (10) is rotated to force-feed the hydraulic oil in the main cylinder (1) on the low pressure side to the high pressure side. At this time, the hydraulic pump (1
The pressure applied to the hydraulic oil by 0) is adjusted by the adjustment weight (13).
The pressure shall be greater than or equal to the weight of the

■ Maximum loading type ffi inside the main elevator cage
(If W> is added In this case, the pressure on the main elevator (4) side will be high by the load of the adjustment weight.
), the communication passage (8) is opened by the speed control valve (11°) on the balance elevator (7) side, and the hydraulic pump (10) is rotated to drain the hydraulic oil in the sub cylinder (6) on the low pressure side. A pressure corresponding to at least the load of the adjustment weight is applied to the main cylinder (1) on the high pressure side, and the main elevator (4) is raised.

Next, in order to lower the main elevator (4), the speed control valve (11) on the main elevator (4) side throttles the communication passage (8), causing the main cylinder (1) on the high pressure side to descend due to the weight of the main elevator (4). The main elevator (4) is lowered and the balance elevator (7) is raised while controlling the speed by moving hydraulic oil from the main elevator to the low-pressure side auxiliary cylinder (6). At the same time, the regenerated power is stored in the inverter or returned to the power source.

■, Energy saving effect - Next, based on this example, balance elevator (7)
We calculated the energy saving effect when using . Table 1 shows the weight of each component of the main elevator and balance elevator.

First of all, the load applied to the balance elevator (7) is always ram weight, fixed weight weight, and adjustable weight mm.
Therefore, i? The static pressure generated in the JI cylinder (6) is determined by the cross-sectional area of the cylinder (35/2) 2π = 96
Since it is 1.6cri, it becomes as shown in equation (4).

2,000 +19.580+7.000 = 29.
7N, 7CIi,... (4)961.6 Next, when there is no load in the cage (2) of the main elevator (4), the static pressure generated in the main cylinder (1) at no 1 load is The cross-sectional area is (30/2) 2π=
706.5C/j, so the equation (5) is obtained.

L 500 + 13.000=2o, c, (<y
/CM,,, (5)706,5 Also, the maximum reconnaissance weight on the main elevator (4) is (13,000
Kg>, that is, the static pressure generated in the main cylinder (1) at full+oad is expressed by equation (6).

From the above, the maximum pressure difference that occurs in the main cylinder (1) and the cylinder (6) is calculated, but in reality there is resistance in the moving part (in this example, when the cylinder rises, +3 to 3/cis -3Kl/ci during descent), so the static pressure in (4), (5), and (6) above differs when the elevator ascends and descends, so it is
1, Ioad, as shown in Tables 2 and 3 below.

From Table 2 and Table 3, the maximum pressure difference is 15.2 kg/d, which corresponds to the maximum horsepower of the motor (9). On the other hand, if the balance elevator (7) is not installed, that is, in the case shown in Fig. 2, the horsepower required for the motor is f.
Since this corresponds to the static pressure when the main elevator (4) rises at 1 oad, 41.9 is 3/cr from Table 3.
I'm here. Therefore 300. If the speed of pushing up the outer diameter ram is the same, the energy consumption will be 1/2 as shown by the following equation
．． Reduced to 75.

15.2 to 3/cri = 1 41.9KFl/crtr, 2.75 [Effects of the Invention] As described above, according to the present invention, it is possible to provide a hydraulic elevator that does not take up much space and is advantageous in terms of layout. It has remarkable effects such as being an energy-saving type with low equipment power consumption.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the present invention, and FIGS. 2 and 3 are explanatory diagrams showing a conventional example. 1...Main cylinder 2...Cage for loading people and/or cargo 3...Main ram 3°...Secondary Ram 4...Main elevator 5...Fixed weight
I6......Sub-cylinder 7...Balance elevator 8...
...Communication path 9...Motor 10...Hydraulic pump it, 11'...Speed control valve 12...Hydraulic circuit 13... ...Adjustment weight 14...Auxiliary hydraulic pump 15...Ram 16...Hydraulic cylinder 17... Wire 18... Pulley 19... Weight 20... Emergency lowering valve Fig. 3

Claims (1)

[Claims] (1) A main elevator that raises and lowers a ram equipped with a cage for loading people and/or cargo by flowing hydraulic oil into or out of the main cylinder, and a balance elevator that consists of a ram equipped with a fixed weight and a sub-cylinder. A communication passage is formed in the cylinders to communicate with each other via a hydraulic pump, and approximately 1/1 of the maximum loading weight is
Attach the adjustment weight of weight 2 to the above fixed weight to reduce the pressure difference between the hydraulic pressure in the communication passage on the main elevator side and the oil pressure in the communication passage on the balance elevator side, and An emergency lowering valve is provided to discharge hydraulic oil, and a pump is provided to correct the relative position of the main cylinder and sub cylinder to supply hydraulic oil to the communication passage on the balance elevator side, so that the main elevator's loaded weight is greater than the adjustment weight. In this case, when the main elevator is to be raised, the hydraulic pump is driven to send hydraulic fluid from the sub-cylinder of the balance elevator to the main cylinder of the main elevator, while when the main elevator is to be lowered, the main elevator is By lowering it by its own weight, the hydraulic oil in the main cylinder flows through the communication path and is sent into the sub cylinder, and the hydraulic oil that flows rotates the hydraulic pump and motor, and the loading weight of the main elevator is smaller than the adjustment weight. In this case, when raising the main elevator, the balance elevator is lowered by its own weight, and the hydraulic oil in the sub cylinder is circulated through the communication passage and sent into the main cylinder, and the hydraulic oil flowing in the cylinder rotates the hydraulic pump and motor. In this case, when the main elevator is lowered, a hydraulic circuit is formed in the communication path to drive the hydraulic pump and send hydraulic oil from the main cylinder to the auxiliary cylinder, and the motor for driving the hydraulic pump is controlled by an inverter. An energy-saving hydraulic elevator characterized by the installation of a device.