JPH05338962A - Hydraulic elevator - Google Patents

Abstract

PURPOSE:To provide a hydraulic elevator which can give a comfortable ride by suppressing a vibration of the car. CONSTITUTION:A speed control device 13 controls the rotation frequency of an electric motor 9 by an inverter 15, and a hydraulic pump 10 is driven by this electric motor 9 so as to control the discharge amount of a hydraulic fluid. The hydraulic fluid is fed to a hydraulic jack 2 so as to push up a plunger 3, and an elevator cage 1 is controlled to operate depending on a specific speed pattern through a pulley 4, and ropes 6a and 6b. The discharge amount of the hydraulic fluid has a pulsation, and if its vibration frequency is made equal to the resonance frequency of the hydraulic system, the plunger 3 vibrates largely. A damper device 8 is installed and composed between the plunger 3 and a pulley holding table 5, thereby, the transmission of the vibration of the plunger 3 to the cage 1 can be suppressed. Consequently, only by attaching a simple damper device, the vibration of the cage 1 can be suppressed, and a hydraulic elevator of a low cost and a comfortable ride can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic elevator, and more particularly to a hydraulic elevator capable of reducing vibration of a car during traveling of the elevator.

[0002]

2. Description of the Related Art In recent hydraulic elevators, a motor rotation speed control system using an inverter has become mainstream due to the progress of power electronics. In this method, the speed of the induction motor is controlled over a wide range by the inverter device, and the rotation speed of the motor is controlled to variably control the discharge amount of the hydraulic oil of the constant discharge hydraulic pump.

In this case, the hydraulic pump is a pump capable of reversible rotation, and its operation is controlled by controlling the rotation of an electric motor that drives the pump during both ascending and descending operations of the elevator.

Incidentally, as a prior art relating to a hydraulic elevator for variably controlling the discharge amount of a constant discharge type pump by changing the rotation speed of an electric motor, for example, there are JP-A-60-248585 and Japanese Patent Application No. 1-2242108. The techniques described are known.

As a conventional technique capable of reducing the vibration of a car, for example, Japanese Patent Laid-Open No. 60-36082.
The techniques described in Japanese Patent Publications and the like are known.

In this prior art, the vibration of the plunger due to the hydraulic resistance and the sliding resistance between the plunger and the cylinder is suppressed by mounting a vibration damping material on the inner peripheral surface of the plunger, and this vibration is applied to the car. It is to prevent it from being transmitted.

[0007]

In the conventional hydraulic elevator using the electric motor speed control method using the inverter device, when the discharge amount of the hydraulic oil from the hydraulic pump has a pulsation, this pulsation is added to the cylinder. There is a problem that the plunger vibrates, and the vibration causes the car to vibrate.

Further, the conventional technique of mounting the vibration damping material on the inner peripheral surface of the plunger has a problem that it is not economical because it is necessary to modify the plunger itself.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide at low cost a hydraulic elevator having a comfortable ride in which the vibration in the car during traveling of the elevator is reduced.

[0010]

According to the present invention, the object is to provide a damper device on the upper part of the plunger, that is, in the case of a direct elevator, in the case of an indirect elevator between the plunger and the car. , By inserting a damper device between the plunger and the pulley to prevent the vibration of the plunger from being transmitted to the car, and in the case of an indirect elevator, using an elastic material for the pulley, And, it is achieved by preventing the vibration in the circumferential direction from being transmitted to the car.

[0011]

[Operation] In the hydraulic elevator using the electric motor rotation speed control method, when the pulsation frequency of the hydraulic oil discharge amount matches the resonance frequency of the hydraulic system, the plunger vibrates greatly and this vibration is transmitted to the car to improve riding comfort. However, since the damper device is inserted in the upper part of the plunger in the present invention, it is possible to prevent the vibration of the plunger from being transmitted to the car or the pulley, and to transmit the vibration to the car. It is possible to suppress and reduce the vibration of the car.

Further, by using an elastic material such as an elastic organic material for the pulley, it is possible to suppress the vibration transmitted to the pulley shaft from being transmitted to the rope due to the damping effect of the elastic material. It is possible to prevent the vibration from being transmitted to the car and reduce the vibration of the car.

[0013]

Embodiments of the hydraulic elevator according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing the overall construction of a first embodiment of the present invention, FIG. 2 is a diagram for explaining the traveling speed characteristics and traveling acceleration / deceleration characteristics of a car, and FIG. 3 is the rotational speed of a hydraulic pump. It is a figure explaining the relationship between (pulsation frequency of discharge amount) and vibration acceleration of a pulley support stand. In FIG. 1, 1 is an elevator car, 2 is a hydraulic jack, 3 is a plunger of the hydraulic jack, 4 is a pulley installed above the plunger, 5 is a support for the pulley, 6a is a rope on the car side,
6b is a fixed-side rope, 7a is a spring used to fix the car-side rope, 7b is a spring used to fix the fixed-side rope, 8 is a damper device inserted between the plunger and the pulley, and 9 is A reversible electric motor, 10 is a hydraulic pump driven by the electric motor, 11 is an electromagnetic switching valve installed between the hydraulic pump and the hydraulic jack, 11a is a signal line for giving a signal to the electromagnetic switching valve, and 12 is hydraulic oil. , 13 is a speed control device, 14 is a speed detector for detecting the speed of the electric motor, 14a is a signal line for feeding back the output of the speed detector, 15 is an inverter for supplying a three-phase power source for controlling the electric motor, 15a Is a signal line that gives a base current to the transistor of the inverter.

The hydraulic elevator shown in FIG. 1 has an inverter 15 controlled by a speed control device 13 and an electric motor 9 driven by a variable voltage and variable frequency electric power from the inverter 15 so that the rotation speed is reversibly rotatable. A hydraulic pump 10 that is driven by the electric motor 9 to flow hydraulic oil between the hydraulic jack 2 and the tank 12, a plunger 3 that is driven by the hydraulic jack 2, and the plunger 3
And a car 1 in which the operation is carried out by ropes 6a and 6b wound around the pulley 4.

In the hydraulic elevator according to the first embodiment of the present invention configured as described above, when the car 1 is in the ascending operation, the speed control device 13 supplies the inverter 15 with the transistor base signal line based on the operation command. A pulse signal is applied through 15a to cause the inverter 15 to generate a three-phase AC power source for controlling the electric motor 9. At this time, the speed control device 13 receives the rotational speed of the electric motor 9 detected by the speed detector 14, and thereby feedback-controls the inverter 15.

The hydraulic pump 10 includes the electric motor 9 as described above.
Driven by the electric motor 9, the discharge rate of the hydraulic oil is controlled. Therefore, the operating oil is the oil tank 1.
2 is sucked up, flows into the hydraulic jack 2 through the check valve of the electromagnetic switching valve 11, pushes up the plunger 3, and
The car 1 is driven up through a pulley 4 and a rope 6a in accordance with a predetermined speed pattern.

The speed control device 13 is used during the descent operation of the car.
Sends a signal to the signal line 11a based on the descending operation command to excite the solenoid of the electromagnetic switching valve 11. As a result, the electromagnetic switching valve 11 is opened and the hydraulic jack 2
The hydraulic oil therein is discharged to the oil tank 12 via the hydraulic pump 10 under the weight of the car 1, the plunger 3, and the like. At this time, since the hydraulic pump 10 is rotated by the discharged hydraulic oil, the electric motor 9 is also rotated, and the inverter 15 regenerates electric power.

In this case, since the rotation speed of the electric motor 9 is controlled by controlling the inverter 15 by the signal from the speed control device 13, the car 1 is controlled to descend according to a predetermined speed pattern.

When the car 1 is operated as described above, the traveling speed characteristic and the traveling acceleration / deceleration characteristic of the car 1 are as shown in FIGS. 2 (a) and 2 (b).

Then, as shown in FIG. 2, when the present invention is not carried out, there is a phenomenon in which vibration as shown by a dotted line occurs in the car 1 at the beginning A portion and the end B portion of the driving, and the passenger 1 It is not preferable because it gives discomfort to the person.

The cause of this vibration is that the vibration occurs only in a specific area of the elevator speed and does not occur outside that area, and therefore it is caused by some disturbance matching the resonance of the hydraulic system. As a result of examination, it has been confirmed that there is a pulsation in the discharge amount of the hydraulic oil from the hydraulic pump 10, and this pulsation causes the pulsation. That is, a two-screw screw pump, which is a general hydraulic pump currently in use, has two pulsations per revolution, and when the rotational speed of the hydraulic pump changes, the pulsation frequency of the discharge amount of hydraulic oil also changes. Then, when the pulsation frequency of the discharge amount of the hydraulic oil of the hydraulic pump is in the speed range where the resonance frequency of the hydraulic system matches, the car 1 will vibrate.

FIG. 3 shows the relationship between the rotational speed of the hydraulic pump 10 (pulsation frequency of the discharge amount) and the vibration acceleration of the pulley support 5. In FIG. 3, when the present invention is not implemented, the characteristics are as shown by the solid line, and the vibration acceleration of the pulley support 5 represents the vibration acceleration of the plunger 3.

Generally, since a hydraulic elevator is hydraulically driven, it is said to be a fluffy system. However, in the case of an indirect hydraulic elevator that drives a car through a rope, a plunger 3 and a pulley 4 are used. Car 1
Since there is a rope 6 between and, there are three resonance frequencies of a fluffy vibration f ₁ of about 2 Hz, a vibration f _{2 of} about 10 Hz, and a vibration f ₃ of about 20 Hz, and a disturbance matching these frequencies exists. When input, the plunger 3 vibrates greatly,
This vibration is transmitted to the car 1 through the pulley 4 and the rope 6, and the car 1 vibrates.

The present invention is characterized in that the vibration of the plunger 3 is not transmitted to the car 1, and the first embodiment of the present invention has an upper portion of the plunger 3 as shown in FIG. That is, the damper device 8 is inserted between the plunger 3 and the pulley 4. And
The damper device 8 includes the top of the plunger 3 and the pulley support 5
Fixed between and.

According to the first embodiment of the present invention in which the damper device 8 is attached, the vibration acceleration of the portion of the pulley supporting base 5 due to the damping effect of the damper device 8 is as shown by the dotted line in FIG. It was possible to reduce the resonances of f ₁ and f ₂ by almost half and to reduce the resonances of f _{3 to} the extent that the resonances of f ₃ were almost eliminated, as compared with the case where the above was not performed. That is, the first embodiment of the present invention can attenuate the transmission of vibrations from the plunger 3, and the pulley 4 can be operated even when the same discharge amount pulsation as the resonance frequency of the hydraulic system is applied from the hydraulic pump 10. The vibration acceleration of can be reduced.

As a result, in the above-described first embodiment of the present invention, as shown by the solid line in FIG. 2 for the acceleration / deceleration characteristics when the car 1 is running, the vibration damping effect described above results in A and B.
It is possible to reduce the vibration of the car 1 in the partial speed range, and to provide a hydraulic elevator that is comfortable to ride and does not cause passenger discomfort.

The damper device 8 in the first embodiment of the present invention described above is not particularly limited, and includes, for example, (1) springs (coil springs, leaf springs, etc.),
(2) Rubber (e.g., elastic organic material) (3) A combination of these materials, (4) Oil damper (a device that obtains a damper effect through oil), and the like can be used.

Further, the mounting position of the damper device 8 in the first embodiment of the present invention is not limited to the portion shown in FIG. 1, and for example, the plunger 3, the pulley support base (bearing portion, etc.) 5 May be attached to.

The above-described first embodiment of the present invention has been described as the application of the present invention to an indirect hydraulic elevator that drives a car through a rope.
The above embodiment can be applied to a direct hydraulic elevator in which a car is directly installed on a plunger, and the same effect can be obtained.

FIG. 4 is a diagram showing the configuration of the second embodiment of the present invention. In FIG. 4, 16 is an elastic material, and other reference numerals are the same as those in FIG.

In the second embodiment of the present invention shown in FIG. 4, in order to prevent the vibration of the plunger 3 from being transmitted to the car 1, a material having a damper effect on the pulley 4, for example, an elastic material 16 made of an elastic organic material is used. Etc. are provided on the outer peripheral portion of the pulley 4.

In the second embodiment of the present invention, by attaching the elastic member 16 having the damper effect to the outer peripheral portion of the pulley 4 as described above, the vertical vibration of the plunger 3 can be reduced, and Since it is possible to expect an effect of damping the vibration acting in the circumferential direction of the pulley 4 and suppress the vibration transmission to the rope 6, the vibration of the car 1 of the above-described first embodiment of the present invention can be suppressed. It can be reduced as in the case.

Therefore, according to the second embodiment of the present invention as well, it is possible to obtain a hydraulic elevator that is comfortable to ride without giving discomfort to passengers.

In the above example, an elastic material such as an elastic organic material is provided on the outer peripheral portion of the pulley 4, but in the present invention, the entire pulley 4 is made of an elastic organic material or the like. The same effect can be obtained in this case as well.

According to the second embodiment of the present invention described above,
Pulley 4 without changing the structure of the hydraulic elevator
It is possible to provide a comfortable hydraulic elevator by changing a part or the whole of the material of the above to an elastic material.

[0037]

As described above, according to the present invention, there is provided a device having a simple damper effect for the car vibration generated by using the hydraulic pump, which is caused by resonance with the pulsation of the discharge amount of hydraulic oil. It is possible to provide a hydraulic elevator that is inexpensive and comfortable to ride because it can be suppressed only by adding it.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a diagram illustrating traveling speed characteristics and traveling acceleration / deceleration characteristics of a car.

[Fig. 3] Rotational speed of hydraulic pump (pulsation frequency of discharge amount)
It is a figure explaining the relationship between and the vibration acceleration of a pulley support stand.

FIG. 4 is a diagram showing an overall configuration of a second exemplary embodiment of the present invention.

[Explanation of symbols]

 1 Car 2 Hydraulic cylinder 3 Plunger 4 Pulley 5 Pulley support 6a, 6b Rope 8 Damper device 9 Electric motor 10 Hydraulic pump 11 Electromagnetic switching valve 12 Oil tank 13 Speed control device 14 Speed detector 15 Inverter 16 Elastic material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiro Ikeda 1-6 Kandanishikicho, Chiyoda-ku, Tokyo Inside Hitachi Building System Service Co., Ltd. (72) Keiichi Senda 1-6-6 Kandanishikicho, Chiyoda-ku, Tokyo Hitachi Building Systems Service Co., Ltd. (72) Masaya Maruoka Inventor Masaya Maruoka 1-6-6 Kandanishikicho, Chiyoda-ku, Tokyo Inside Hitachi Building Systems Services Co., Ltd. (72) Hiromi Inaba 4026 Kuji Town, Hitachi City, Ibaraki Prefecture Co., Ltd. Hitachi Research Laboratory, Hitachi, Ltd. (72) Yoshio Sakai, 1070 Ma, Ichi, Katsuta, Ibaraki Hitachi, Ltd., Mito Plant

Claims (3)

[Claims] 1. In a hydraulic elevator in which hydraulic oil is supplied to a hydraulic jack by a hydraulic pump whose rotation is controlled by an electric motor, and a plunger is driven by the pressure of the hydraulic oil to drive a car, a damper device is provided above the plunger. A hydraulic elevator characterized by comprising. 2. A hydraulic pump is rotated by an electric motor to supply hydraulic oil to the hydraulic jack, and the plunger is driven by the pressure of the hydraulic oil so that the car is moved through a pulley and a rope provided on the plunger. A hydraulic elevator for traveling, comprising a damper device between the plunger and the pulley. 3. A hydraulic pump that is rotationally controlled by an electric motor supplies hydraulic oil to a hydraulic jack, and the plunger is driven by the pressure of the hydraulic oil, so that a car is moved through a pulley and a rope provided on the plunger. A hydraulic elevator for traveling, characterized in that all or part of the pulley is made of an elastic material.