JP2001192185A - Shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shock absorber formed by a hydraulic shock absorber set in multi-stage telescopic type, in which an expansion means for returning the absorber to the most expansion state will not make the shock absorber expensive, and which will not require troublesome maintenance. SOLUTION: In this shock absorber in which an uppermost stage rod member 4 is sunk in an uppermost stage cylinder body 3 so that the uppermost stage cylinder body 3 sinks into a medium stage cylinder body 2, and the medium stage cylinder body 2 is sunk in the lowermost stage cylinder body 1 to effect a designated damping action, a lower air chamber A partitioned in the lowermost stage cylinder body 1 by a piston part 2a forming the lower end part of the medium stage cylinder body 2 slidably stored in the lowermost cylinder body 1 is set to a gas spring chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a shock absorber used for stopping a descending elevator at the lowest floor.

[0002]

2. Description of the Related Art There have been various proposals for shock absorbers used when stopping a descending elevator at the lowest floor. Among them, a shock absorber has a rod body with respect to a cylinder body. In the case of a shock absorber to be immersed under a damping action, for example, a hydraulic shock absorber, the hydraulic shock absorber has often been set to a so-called single-acting type.

[0003] That is, since the speed in a conventional elevator was not as fast as today, the deceleration required to stop the elevator at the lowest floor, for example,
I was able to do enough with a clamp-type brake device.
Even if a sufficient braking effect could not be obtained, it was sufficient that the shock absorber be of the minimum necessary as long as it does not adversely affect the people in the elevator.

[0004] However, some recent elevators have been increased in speed so that the speed becomes 800 m or more per minute. When such a high-speed elevator is stopped, a person inside the elevator is required. In consideration of the influence of gravity or the like acting on the floor, a distance corresponding to the height of the second or third floor is required.

[0005] Even if the deceleration at that time is realized by a clamp type brake device, it cannot sufficiently cope with it. Therefore, in order to stop such an elevator descending at a high speed at the lowest floor, a shock absorber must be provided. There is a proposal to set the hydraulic shock absorber to be configured as a telescope type, that is, a multistage telescopic type.

When the hydraulic shock absorber constituting the shock absorber is set to a multi-stage telescopic type, not only can a predetermined shock absorbing effect be secured, but also the oil shock absorber constituting the shock absorber is a so-called single-acting type. There is an advantage that the size at the time of the most contraction can be reduced as compared with the case where is set to.

However, in order to return the hydraulic shock absorber, which has become almost unloaded, that is, the shock absorber to the most extended state, an elongating means for generating a so-called restoring force is required. In order to return the shock absorber to the maximum extension state, an extension means having a large extension stroke is required.

At this time, when an actuator including a hydraulic cylinder or the like is used as the extension means, it is necessary to equip a hydraulic supply / discharge source having a tank, a pump, and an adjustment valve for controlling the expansion and contraction of the actuator. As a result, there is a problem that the cost of the shock absorber is increased and the time and effort for maintenance are increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a multi-stage telescopic hydraulic shock absorber.
The extension means for returning this to the maximum extension state does not make the shock absorber expensive and does not require time-consuming maintenance, and provides an optimal means for expecting improvement in versatility. It is.

[0010]

In order to achieve the above-mentioned object, the structure of the shock absorber according to the present invention basically includes a lowermost cylinder body and a lower and upper cylinder body. A middle cylinder body serving as a lowermost rod body, an uppermost cylinder body serving as a middle rod body protruding and retracting with respect to the middle cylinder body, and an uppermost cylinder body protruding and retracting with respect to this topmost cylinder body And the uppermost rod body is immersed in the uppermost cylinder body, so that the uppermost cylinder body is immersed in the middle cylinder body, and the middle cylinder body is located in the lowermost cylinder body. In the shock absorber configured so as to achieve a predetermined damping action by being immersed in the cylinder body, a lower end portion of the middle cylinder body slidably housed in the lowermost cylinder body. By ton unit to a lower air chamber partitioned into a cylinder body of the bottom is set to the gas spring chamber.

[0011] In the above structure, more specifically, the lower air chamber defined in the lowermost cylinder body is formed as a gas spring chamber with a lower end of the lowermost cylinder body closed. Alternatively, it is assumed that the air chamber is communicated with an air chamber formed between the lowermost cylinder body and a cylinder disposed on the outer peripheral side.

A piston is disposed on the outer periphery on the upper end side of the lowermost rod body which does not protrude and retract from the lowermost cylinder body, while the piston is disposed on the inner periphery on the outer peripheral side on the upper end side of the rod body. An inner cylinder for slidingly contacting the outer circumference of the piston is disposed, and an outer cylinder is disposed with an appropriate gap on the outer peripheral side of the inner cylinder, and the inner cylinder is disposed at an upper end of the inner cylinder. Through holes that allow communication on the inner and outer sides are opened,
From the upper end to the lower end of the inner cylinder, a number of orifices are formed to allow communication between the inner and outer peripheral sides of the inner cylinder, and the inner periphery of the inner cylinder which is below the piston when the rod body is lowered is lowered. The working fluid on the side flows out to the outer peripheral side of the inner cylinder through an orifice opening on the inner peripheral side of the inner cylinder, and is above the piston via the above-mentioned through hole and the orifice opening on the inner peripheral side of the inner cylinder. It is assumed that it is set so as to flow into the inner peripheral side of the inner cylinder.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on the illustrated embodiment. As shown in FIG. 1, even in the shock absorber according to the present invention, a multistage telescopic hydraulic It is said that it consists of a shock absorber.

That is, as shown in the drawing, the shock absorber has a lowermost cylinder body 1 and a middle cylinder body 2.
And an uppermost cylinder body 3 and an uppermost rod body 4.

When the uppermost rod body 4 is immersed in the uppermost cylinder body 3, the uppermost cylinder body 3 is immersed in the middle cylinder body 2. Are immersed in the lowermost cylinder body 1 so that the damping mechanism 5 achieves a predetermined damping action.

First, the lowermost cylinder body 1 has the above-described damping mechanism 5 at its upper end, while in the illustrated embodiment, a hoistway (not shown) on which an elevator (not shown) moves up and down. In FIG. 3), the pit floor P, which is the lowest floor, is supported in a fixed state in a so-called upright state.

Here, the damping mechanism 5 will be briefly described. The damping mechanism 5 includes a piston 51, an inner cylinder 52,
And an orifice 52a selected from a number of orifices 52a opened in the inner cylinder 52.
The above-mentioned predetermined damping action is realized by the passage of a working fluid such as oil.

That is, the piston 51 is provided on the outer periphery of the upper end side of the middle cylinder body 2 which protrudes and retracts with respect to the lowermost cylinder body 1, that is, the middle stage cylinder body which does not protrude and protrude from the lowermost cylinder body 1. It is provided integrally with the outer periphery of the upper end side of the cylinder body 2, and its outer periphery is slidably in contact with the inner periphery of the inner cylinder 52.

At this time, the piston 51
An upper oil chamber 54 and a lower oil chamber 55 are defined between the outer periphery of the middle cylinder body 2 and the inner cylinder 52.

The inner cylinder 52 is provided with the above-mentioned middle cylinder body 2.
And a plurality of orifices 52a which are opened and drilled from the upper end to the lower end to allow communication between the inner and outer peripheral sides of the inner cylinder 52. A through hole 52b that allows communication between the inner and outer peripheral sides of the inner cylinder 52 is formed.

Incidentally, the inner peripheral side of the inner cylinder 52 referred to herein is, of course, the upper oil chamber 54 and the lower oil chamber 55 described above.

The outer cylinder 53 is provided on the outer peripheral side of the inner cylinder 52 with an appropriate gap serving as a passage for the working fluid. By providing the outer cylinder 53, This constitutes a closed circuit in the damping mechanism 5.

Therefore, in the damping mechanism 5, when the lowermost rod body is lowered, that is, when the middle cylinder body 2 is immersed in the lowermost cylinder body 1, the lower part of the piston 51 is moved downward. The working fluid in the lower oil chamber 55 flows out to the outer peripheral side of the inner cylinder 52 through the orifice 52a opened to the lower oil chamber 55, and the through-hole 52b and the upper oil chamber 54
Flows into the upper oil chamber 54 above the piston 51 through the orifice 52a opening to the side, and a predetermined damping action is realized when the working fluid passes through the orifice 52a.

At this time, as shown in the figure, only the working fluid filled in the damping mechanism 5 participates in the damping action. Therefore, the viscosity of the working fluid, that is, the fluid filled in the shock absorber main body, ie, oil Therefore, selecting the viscosity of the working fluid is advantageous in that the level of the generated damping force by the damping mechanism 5 can be adjusted.

In the drawing, the number of orifices 52a opening to the lower oil chamber 55 decreases as the middle cylinder body 2 descends, so that the damping force gradually increases.

On the other hand, the lowermost cylinder body 1 described above
It has a lower air chamber A and an upper oil chamber R defined by a piston portion 2a serving as a lower end of a middle cylinder body 2 slidably housed therein, and the upper oil chamber R is a middle cylinder. It is said that it is communicated within the body 2.

At this time, the lower air chamber A is a gas spring chamber which is formed by closing the lower end of the lowermost cylinder body 1 and is filled with a gas such as air.
When the lower air chamber A is contracted by the lowering of the piston portion 2a, a gas spring effect is exerted.

Next, as described above, the middle cylinder body 2 is a lowermost rod body which protrudes and retracts with respect to the lowermost cylinder body 1 and is slidably housed therein. It is assumed that the upper cylinder body 3 has a lower oil chamber R1 and an upper oil chamber R2 defined by a piston portion 3a serving as a lower end of the upper cylinder body 3, and the upper oil chamber R2 is communicated with the uppermost cylinder body 3. I have.

At this time, the middle cylinder body 2 has a through hole 2b opened above the piston portion 2a, and the lower oil chamber R1 is connected to the upper oil chamber R1 through the through hole 2b. It is stated that the communication with the oil chamber R is made.

Further, the uppermost cylinder body 3 is a middle rod body that protrudes and retracts with respect to the middle cylinder body 2. It has a lower oil chamber R3 and an upper oil chamber R4 defined by a piston portion 4a serving as a lower end.

At this time, the uppermost cylinder 3
Has a through hole 3b opened above the piston portion 3a, and the lower oil chamber R3 communicates with the upper oil chamber R2 via the through hole 3b.

Further, the uppermost rod body 4 protrudes and retracts with respect to the uppermost cylinder body 3, and the lower oil chamber R3 and the upper oil chamber R4 are provided at the lower end of the piston part 4a.
It has a through-hole 4b communicating with the hole.

Therefore, in the shock absorber thus formed, the load acting on the uppermost rod body 4 causes this rod body 4 to enter the uppermost cylinder body 3 and The uppermost cylinder body 3 is sunk into the middle cylinder body 2, and the middle cylinder body 2 is sunk into the lowermost cylinder body 1.

At this time, the relationship between the cross-sectional area of the uppermost rod body 4 and the inner peripheral cross-sectional area of the uppermost cylinder body 3, and the outer peripheral cross-sectional area of the uppermost cylinder body 3 and the interrupted cylinder body 2 and the inner peripheral cross-sectional area of the cylinder body 1 at the lowermost stage are set under necessary conditions. That is, since the uppermost rod body 4 is immersed in the uppermost cylinder body 3, excess oil in the lower oil chamber R <b> 3 in the uppermost cylinder body 3 becomes higher in the middle cylinder body 2. It will flow into the oil chamber R2.

Therefore, when the upper oil chamber R2 expands, the uppermost cylinder body 3 is immersed in the middle cylinder body 2. At this time, the lower oil chamber R2 in the middle cylinder body 2 The excess oil in R1 flows into the upper oil chamber R in the lowermost cylinder body 1.

As a result, the upper oil chamber R expands, so that the middle cylinder body 2 is immersed in the lowermost cylinder body 1, and finally, the shock absorber is most compressed. become.

When the middle cylinder body 2 enters the lowermost cylinder body 1, a predetermined damping action is realized by the damping mechanism 5 as described above. The descending speed can be reduced.

At this time, the lower air chamber A partitioned in the lowermost cylinder body 1 is contracted to exhibit a predetermined gas spring effect. When the load acting on the rod body 4 is no longer present, that is, when the shock absorber is in a no-load state, the shock absorber is returned to the most extended state.

Therefore, the gas spring chamber exhibiting the air spring effect, that is, the lower air chamber A is the extension means in the present invention for returning the shock-absorbing device in the no-load state to the maximum extension state.

According to the above, according to the present invention, the lower air chamber A, which is a closed air chamber, can be used as the extension means, so that it is not necessary to separately provide an actuator as the extension means. By providing such a structure, there is no fear that the cost of the shock absorber may be unnecessarily increased, and further, it is advantageous in that complicated maintenance is not required.

Further, from the viewpoint that the lower air chamber A serves as an extension means for exhibiting the air spring effect, although not shown, the lower air chamber A is not an enclosed space but an open space. By disposing the coil spring and using the coil spring as the extension means, the shock-absorbing device in a no-load state can be returned to the maximum extension state. However, even in this case, there is a disadvantage that a component as a coil spring is required. Further, there is a disadvantage that maintenance is required as long as the coil spring is provided.

As described above, the lower air chamber A as the extending means in the present invention formed as described above is formed by closing the lower end of the lowermost cylinder body 1. Instead, as shown in FIG.
It may be configured to communicate with an air chamber A1 formed as a closed space between the lowermost cylinder body 1 and the cylinder body 6 arranged on the outer peripheral side.

At this time, in this embodiment, it is assumed that a through hole 1a is formed in the lower end of the lowermost cylinder body 1, and the lower air chamber A is connected to the air chamber A1 through the through hole 1a. It is said that they will communicate.

In this embodiment, parts having the same structure as that of the embodiment shown in FIG. 1 are denoted by the same reference numerals in FIG. Is omitted.

Also in this embodiment, the lowermost cylinder 1 constituting the shock absorber is a pit floor P
In a so-called upright state, it is said to be supported in a fixed state.

In consideration of the function of the air chamber A1, the air chamber A1 does not need to be formed integrally with the outer peripheral side of the lowermost cylinder body 1; The cylinder body 1 may be formed as a separate body from the cylinder body 1 and both may be connected to each other by a pressure-resistant hose or the like.

When the air chamber A1 is formed separately and communicated with a pressure-resistant hose or the like, it is necessary to open the through hole 1a, but the embodiment shown in FIG. 1 can be used as it is. Is advantageous.

In the embodiment shown in FIG. 2, the lower air chamber A is communicated with the outer air chamber A1, so that the so-called air chamber can be enlarged. The effect can be lessened than in the above-described embodiment.

On the other hand, as compared with the above-described embodiment, the middle cylinder body 2 serving as the lowermost rod body can descend in the lowermost cylinder body 1 with a so-called long stroke. However, there is a concern that the stroke may be too long.

Therefore, in such a case, as shown by a phantom line in the drawing, the stroke adjusting means 7 is provided in the lower air chamber A, and the length of the stroke of the middle cylinder body 2 is optimized. It may be adjusted as follows.

[0051]

As described above, according to the present invention, when the shock absorber comprises a multi-stage telescopic hydraulic shock absorber, the shock absorber can be inserted into and retracted from the lowermost cylinder. By setting the lower air chamber defined by the piston at the lower end of the middle cylinder body to be inserted as the gas spring chamber, this gas spring chamber can be used as the expansion means in the shock absorber with no load. There is no need to provide an actuator separately, and there is no danger that the provision of the actuator may lead to an unnecessary increase in the cost of the shock absorber, and furthermore, there is an advantage that no complicated maintenance is required.

As a result, according to the present invention, when the shock absorber comprises a multi-stage telescopic hydraulic shock absorber, the extension means for returning the shock absorber to the maximum extension state does not make the shock absorber expensive, and This is ideal for expecting improved versatility without requiring complicated maintenance.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing in principle a shock absorber according to an embodiment of the present invention.

FIG. 2 is a diagram showing a shock absorber according to another embodiment, similarly to FIG.

[Explanation of symbols]

 1 Lowermost cylinder body 1a, 2b, 3b, 4b, 52b Through hole 2 Middle cylinder body 2a, 3a, 4a serving as bottom rod body Piston part 3 Top cylinder body serving as middle rod body 4 Top Upper rod body 5 Damping mechanism 6 Cylindrical body 7 Stroke adjusting means 51 Piston 52 Inner cylinder 52a Orifice 53 Outer cylinder 54, R, R2, R4 Upper oil chamber 55, R1, R3 Lower oil chamber A Lower gas chamber Air room A1 Air room P Pit floor

Claims (1)

[Claims] 1. A lowermost cylinder body, a middle cylinder body serving as a lowermost rod body protruding and retracting from the lowermost cylinder body, and a middle rod body protruding and retracting from the middle cylinder body And an uppermost rod body that protrudes and retracts with respect to the uppermost cylinder body. In the shock absorber, the upper cylinder body is immersed in the middle cylinder body, and the middle cylinder body is immersed in the lowermost cylinder body so that a predetermined damping effect is realized. A lower air chamber partitioned by a piston portion serving as a lower end portion of the middle cylinder body slidably housed in the lower cylinder body is set as a gas spring chamber. Shock absorber