JPS60109631A - Diaphragm type air spring - Google Patents

Abstract

PURPOSE:To enable load supporting capability of the captioned spring to be properly set and thereby improve vibration damping performance by constructing large and small air chambers such that a ratio between effective pressure receiving areas thereof can be changed at need, in the differential type air spring provided with the large and small two air chambers. CONSTITUTION:Large and small air chambers 1, 2 are partitioned by a bulkhead 3 and communicated with each other by an orifice 4 provided on the bulkhead 3. Respective large and small pistons 15, 18 of the air chambers 1, 2 are coupled to each other with a rod 11. Diaphragms 7, 10 are disposed between the large and small pistons 15, 18, and large and small shells 6, 9 respectively. Outer circumferences of the large and small pistons 15, 18 are gradually changed in the axial direction. Hereby, a ratio between effective diameters, namely, between effective pressure receiving areas of the large and small air chambers 1, 2 changes at need in responce to moving distances of the pistons 15, 18 and further amounts of compression deformations thereof, thus enabling load supporting capability to be properly set depending on the shapes of the pistons 15, 18.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called differential type diaphragm air spring having two large and small air chambers.

Since this type of air spring is small and provides a large vibration damping force, various structures have been proposed in recent years.

FIG. 1 is a cross-sectional view showing a differential type diaphragm air spring that the applicant previously proposed in Japanese Patent Application No. 186888/1988. In the figure, 1 indicates a large air chamber, and 2 indicates a small air chamber. show.

These large and small air chambers 1 and 2 are separated by a partition 8 and communicated with each other by an orifice provided in the partition 3.

Here, the large air chamber 1 includes a large-diameter piston 5, a large-diameter outer shell 6 that faces the large-diameter piston 5, has a larger inner diameter, and is coaxial with the large-diameter outer shell 6, and in the illustrated example, the upper end of the large-diameter piston 5. The small air chamber 2 includes a diaphragm 7 airtightly connected to the lower end of the large diameter outer shell 6, and the small air chamber 2 faces a small diameter piston 8 disposed on the same axis as the large diameter piston 5 and this piston. A small-diameter outer shell 9 that is integral with the large-diameter outer shell 6; and a diaphragm 10 that is folded back in the opposite direction to the diaphragm 7 and airtightly connects the lower end of the small-diameter piston 8 and the upper end of the small-diameter outer gel 9. These large and small air chambers 1.2 penetrate the partition and wall 3, and
On the other hand, Surizai is very good.

The large and small pistons 5.8 are connected to each other by means of a rod 1. Such a diaphragm-type air spring can be used, for example, to connect the large diameter cylinder side to the installation floor side of a vibrating machine or the like, or to connect the outer The respective connection of the shell side to the machine side provides load support and effective damping of vibrations.

Now, looking at the vibration damping effect of this air spring, for example, from the bottom of the spring, the large diameter piston 5 & C1 are shown by arrow A.
When an upward vibration as shown in is transmitted, the volume of the large air chamber 1 decreases and the pressure p sealed therein increases by Δp□, while the volume of the small air chamber 2 increases and its Since the internal pressure decreases by Δp2 from the filling pressure p, both air chambers 1
．． The differential pressure between the two is Δp0+Δp2. For this reason, the air in the large air chamber flows into the small air chamber 2 through the diameter of the second refit 4 until the differential pressure Δp + Δp disappears, and the vibration is damped by the stiffness. Even when directional vibrations are transmitted, the increase and decrease in pressure in both air chambers 1.2 is the same as in the case described above.

However, in such a diaphragm-type air spring, the large and small pistons 5 and 8 all have a uniform length over their entire length.
The deflection characteristics are always approximately linear as shown by the solid line in FIG. 2, and the spring characteristics do not change.

The present invention advantageously solves these problems of the diaphragm type air spring, and can sufficiently attenuate various vibrations from cylindrical frequency 1--small amplitude vibrations to large amplitude vibrations, and moreover, The present invention provides a new diaphragm-type air spring that can sufficiently increase the durability of the diaphragm.

In particular, the diaphragm air spring of the present invention is formed by gradually changing the circumference of at least one of the pistons in its axial direction. The deformed shape of the diaphragm can be varied as required to suitably change the load carrying capacity (σ), resulting in a variable spring with any desired properties. In other words, when it is used in a vibrating machine or the like, it is possible to realize a soft spring and sufficiently effectively attenuate all the vibrations transmitted thereto. 0 will be explained based on an illustrated example.
FIG. 8 is a cross-sectional view showing one embodiment of the present invention, in which parts similar to those shown in FIG. 1 are designated by the same numbers.

The large and small pistons 15 and 18 in this example each have a truncated conical shape that gradually becomes smaller in diameter toward the lower and upper ends,
These pistons 15 and 184 are concentrically connected by a rod 11 passing through the partition wall 8.

Ru.

The configuration of other parts is the same as that shown in FIG.

The diaphragm air spring constructed in this manner has a vibration damping effect by the piston movement similar to that described in connection with FIG. Go, do it.

However, according to this air spring, Fig. 4(a).

As shown in (b), the compressive deformation process is shown in FIG. The effective diameters of the large and small air chambers 1 and 2, or in other words, the ratio of effective pressure receiving areas, change as required.

Considering this for the fourth [J(al, (b)), the ratio of the effective diameter of the small air chamber 2 to the effective diameter of the large air chamber 1 decreases as the amount of compressive deformation increases. Depending on the size, the load carrying capacity of the air spring will vary in a desired manner.

The broken line in FIG. 2 shows the load-deflection curve of the air spring constructed in this way.According to this curve 1--line, the air spring is an extremely soft spring, especially under small loads. It can be seen that this is a variable spring that has characteristics and does not have a high rigidity even under large loads.

FIG. 5 is a sectional view showing another embodiment of the present invention, in which only the small diameter piston is placed in the third embodiment according to the desired load-deflection characteristics.
The structure shown in the figure is similar to that shown in FIG. 1, and the large diameter piston is the same as that shown in FIG.

Also in this example, as in the above-mentioned example, a load supporting capacity corresponding to the shape of the small diameter piston 18 can be obtained.

In addition, in order to provide the desired load supporting characteristics, only the large diameter piston should have the configuration shown in FIG. 8, the piston shown in FIG. to do the opposite.

It is also possible to change the taper angle of the piston, to curve the circumferential pupil of the piston, or to form either the large or small piston into a shape constricted in the middle, as shown in FIG.

FIG. 7 is a cross-sectional view showing an embodiment of the Zaraaniike according to the present invention, in which a small-diameter piston is tapered toward a small air chamber. In this example, the large diameter outer shell 6 and the small diameter outer shell 9 are separated, and the large diameter outer shell A/6;! p. The small-diameter piston 28G, which curves upward and becomes small in diameter, is integrally connected, and the top wall of the small-diameter outer shell 9, which is disposed opposite to the small-diameter piston 28, is connected to the small-diameter piston 28G.

Rods passing through the top wall of the piston 2B] L, J niches are connected to the large diameter piston 5.

This example also provides load-bearing characteristics depending on the shape of the 41-diameter piston 28, similar to the previous example.

In this example as well, it is of course possible to change the shape of the piston in the same way as in the case described above. Therefore, according to the present invention, at least By appropriately selecting the shape and dimensions of the piston, a variable spring whose air spring σ) load-bearing characteristics can be varied as required can be obtained. For this reason, for example, if an air spring is configured as shown in FIG. 3G, a soft spring is obtained, and vibrations at each frequency are sufficiently damped.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view showing a conventional example; Figure 2 is a line diagram showing the load-deflection characteristics of bellows type air spring σ; Figure 3 is a cross-sectional view showing an embodiment of the present invention. 5 is a sectional view showing another embodiment of the invention, FIG. 6 is a side view illustrating the shape of the piston, and FIG. 7 is an actual example of a piston. FIG. 1... Large air chamber 2... Small air chamber 3... Partition wall 4... Orifice 6... Large diameter outer shell 7.01... Diaphragm 9... Small diameter outer shell 1]...・Rod 1
5...Large diameter piston 18, 28...Small diameter piston. Figure 5 Figure 7 Figure 6 (a> (b)

Claims (1)

[Scope of Claims] L: Two large and small air chambers separated by a partition wall, an orifice provided in the partition wall that allows these rain air chambers to communicate with each other, and a piston or large air chamber for each air chamber. In a diaphragm air spring having a rond that integrally connects the piston and the outer shell of the small air chamber, the length of one of the pistons is gradually changed in the axial direction. A diaphragm type air spring characterized by: