JPS5891945A - Vibration reducing valve for shock absorber - Google Patents

Abstract

PURPOSE:To maintain a constant damping force over the whole range of a high piston speed by mounting a disc valve composed of a Belleville spring in a preliminarily deformed state so as to keep a constant load during deformation. CONSTITUTION:Orifice plates 12, 12' and disc valves 13, 13' are composed of a Belleville spring, respectively. Slits 12a, 12'a are formed on the inner periphery end of said orifice plates 12, 12'. These orifice plates 12, 12' and disc valves 13, 13' are mounted on a valve 8 upon condition that they are preliminarily deformed by means of a spring 11 through a retainer 10 so as to keep a constant load during their deformation. In this case, it is desirable that the free height H1, H2 of said orifice plate 12 and said disc valve 13 are about 2<1/2> times thickness t1, t2, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration damping pulp for shock absorbers used for the purpose of damping rebound vibrations in suspension systems of military vehicles.

Shock absorbers are known in rear cylinder type and single cylinder type *M types, but in both cases, the pulp (vibration damping pulp) that controls the vibration damping function is usually composed of a disc valve. be.

ζ Now, to explain the conventional shock absorber and its vibration damping valve pipe for the rear cylinder type vehicle, these were constructed as shown in FIG. 91. In this figure, lFi is the inner cylinder, C is the outer cylinder which is normally connected to the suspension system, J is the piston which is usually connected to the vehicle body, +q piston rond, ! 16 is the cylinder chamber, 7 is the reservoir chamber, and r is the cylinder chamber! ,6
Vibration damping pulp (
piston pulp), cylinder chamber 6 and reservoir chamber 7
A vibration damping pulp (bottom pulp) provided at the bottom of the inner cylinder 11 to be inserted between the cylinders 11 and 11 is shown. A working fluid pipe is sealed in tt6 and a part of the reservoir chamber 7, and a high pressure gasket is sealed in the remaining part of the reservoir chamber 7.

When vibration is input to the outer cylinder through the suspension system, in the shock absorber's contraction stroke, the piston rod≠ is inserted in the direction shown by the solid arrow in figure wJ1 relative to the outer cylinder λ.
The pressure in the cylinder N6 becomes high and a pressure difference is generated before and after the piston pulp l, and this pressure difference causes the retainer 10 to resist the spring ii and move to the open position shown in FIG. , 6, the working fluid pipe can freely flow back and forth between the two. Therefore, although the piston rod q tries to perform the insertion stroke smoothly, the volume of insertion causes high pressure in the cylinder chamber 6, and a pressure difference is generated before and after the bottom valve. This differential pressure is narrowed by the reservoir through the inner circumferential edge slit l/aQ of the working fluid pipe orifice pre-nid l' in the cylinder chamber 6, restricting the displacement flow of the working fluid before and after it, and generating a damping force. do.

Furthermore, during the shock absorber's extension stroke in which the piston rod is pulled out in the direction shown by the dotted arrow in FIG. 1, the cylinder chamber j becomes high pressure and the retainer 10? *The damping force is maintained in the closed position shown in the figure j, and the displacement flow of the working fluid to be performed before and after the piston pulp l is limited to the flow rate determined by the slit saw a on the inner peripheral edge of the merit plate l. occurs. On the other hand, when the piston rod is withdrawn, the pressure in the cylinders 1iir and t becomes low due to the volume of the withdrawal, and a pressure difference is generated before and after the p1 bottom valve.

This differential pressure displaces the retainer against the spring io'2 to bring it into the open position, allowing the working fluid to flow freely before and after the bottom valve, thereby compensating for the change in volume due to the withdrawal of the piston rod.

Due to the above action, the shock absorber controls the vibration damping function with the damping force generated in both the contraction stroke, ripening stroke, and extension stroke, and the speed of the damping force piston is as shown in the figure below.
During the low speed range up to the value shown by , as shown by a in the figure, it is determined by the opening area of the slits l core a, /co'a, and increases to the λ-order curve contract.

However, in a piston speed range higher than that, for the piston pulp l, the differential pressure increases and the orifice spray) /, Zll - supporting disc pulp /
3 (In case of bottom pulpor/J') Deform together with f orifice plate/co in the pulp opening direction as shown in the KllGJ diagram. Therefore, in the piston speed range, the displacement flow of the working fluid is less restricted, and the damping force is determined by the spring force of the disk pulp/J, as shown in IQKb, and the damping force becomes excessive. prevent it from becoming

By the way, in the past, the disk pulp /J, /J', which determines the damping force t of high piston speed, was made flat in a free state together with the orifice plate /2, that is, the piston pulp l 2911th
As shown in Figure 941, the disk pulp /J, /J' and the orifice plates lco, lco' are normally held together by springs //, //' as shown in Figure 941.
In order to assemble the retainers 10, 10' so that they are deformed, the disk pulp /J, /J' and the orifice spray) /J, /, 21 are due to the differential pressure! When forming, the spring force is gradually increased, and therefore the damping force characteristic shown in diagram @4I also has a slope corresponding to this. For this reason, in conventional shock absorbers, as the piston speed increases, the damping force tends to be excessive, causing a worsening of the ride comfort of the vehicle.

The #-1t disc spring of the present invention has a spring force change characteristic as shown in FIG.
Focusing on the point that #1 has a constant spring force (constant load) 1 between α2, if it is deformed by the differential pressure in this region and used as disc pulp for disc spring society, the disc pulp will be The present invention aims to provide a vibration damping valve system for a shock absorber which embodies this idea from the viewpoint of being able to solve the above-mentioned conventional problems due to constant load during operation.

Hereinafter, the present invention will be explained in detail based on the illustrated embodiment.

In the present invention, as shown in FIG. 6(a) and FIG. 6 middle), the orifice spray) /2. /, 2' and disk pulp /J, /J' f are each constructed with a disc spring, and orifice sprays) /J, /co' have slits /co&, /co/a1'' formed on their inner peripheral edges.

Among such orifice plates and disc pulps, orifice spray) /, 2 and disc pulp /
When constructing a piston valve rt using Jt, these are assembled as shown in FIG. That is, the orifice plate/J and the disc pulp 13IIi are overlapped in the same manner as before, but in order to maintain a constant load during deformation due to the differential pressure between the front and rear of the piston pulp t, this deformation is carried out between the deformation amounts α1 and α2 in Fig. 3. spring l
/ is installed in a pre-deformed state through the retainer lOt.

Regarding the bottom pulp P (see Fig. 1), in the present invention, the disc spring type orifice spray /J' and the disc pulp /J' shown in Fig. 6 are assembled in the same manner, and the bottom pulp is processed. Can be configured.

The vibration-damping pulp of the present invention having such a structure functions in the same manner as described above due to the differential pressure between the front and rear of the piston pulp, but due to the differential pressure, the orifice plates l, 2 and Kagiri reaches the stage corresponding to FIG. 3, where the disk pulp 13 deforms,
The deformation of the orifice plate lλ and the disc pulp /J falls within the deformation amount α1 to α2 shown in FIG. 5, and is a constant load, so the spring tension is kept approximately constant.

Therefore, the damping force of the shock absorber made of the vibration-damping pulp of the present invention becomes almost the same in the region of piston speed v1 or higher, as shown by b' in the figure, and even when the piston speed is high, the damping force becomes too large. Impairing the comfort of the vehicle.

Here, constant damping force b' H orifice plate/-
By determining the total value of the constant load at the time of assembling the disc pulp 13 and making this the required load r0, the damping force b'1 can be determined to a desired value.

In addition, due to the above-mentioned effect, the constant load area α in Fig. 3
1~α2F! It is better to make the width as wide as possible, and in this sense, we confirmed that it is better to make the free heights of the disk pulp 13 (Hl and H2V) approximately 0 times the thickness of 11.12. I met.

The @r diagram shows another example of the present invention, and in this example, the wJr diagram (s
A sulin) /Ja tl- is formed on the inner peripheral edge of the disc pulp /3 made of disc springs as shown in L). In this case, the orifice plate 1 can be omitted since Surin)/JJL serves as the orifice sound and disk pulp/3 serves as the orifice spray)/2.

In addition, when using the configuration of disk pulp/3f@I diagram (a), multiple sheets are stacked as shown in the t-application diagram, and l@ of them is replaced with another one to apply the load F0 (1st/! E
It is also possible to fine-tune the parameters (see 1).

Further, even if the disk pulp 13 does not have the configuration shown in FIG. 1(a), it is possible to omit the orifice plate saw even if the structure shown in FIG. 6(b) is not changed, and an example thereof is shown in FIG. In this example, the orifice/117a, which functions similarly to the orifice plate saw's sulin)/komi, is attached to the retainer 10.
A through hole lob'gr is bored in the retainer IQ so as to face the inner peripheral edge of the disk pulp /3. In this case, the pressure difference between the front and rear of the piston pulp r concentrates on the inner peripheral edge of the disc pulp/J, and the disc pulp 13 is deformed due to the pressure difference v.
Make it ex.

Thus, the vibration-damping pulp of the present invention is composed of the disc pulp/Jf disc spring as described above, and the disc pulp 13 is attached in a pre-deformed state so that it is under constant load during deformation due to the differential pressure across the disc pulp. Is there a damping force in the high piston speed range where 13 is deformed? It is possible to keep the damping force constant and prevent the damping force from becoming excessive as the piston speed increases, thereby preventing the ride comfort of the vehicle from being impaired in this region.

[Brief explanation of the drawing]

＠ / Figure is a lower vertical side view of a general shock absorber, Figures - and 3 are sectional views for explaining the action of the piston pulp of the same shock absorber, and Figure 4 is a diagram of the action characteristics of a conventional vibration damping valve. I! ! The figure is a spring force change characteristic diagram of a disc spring, Figure 6 is a sectional view of an orifice plate and a disc valve used in the vibration damping valve of the present invention, and Figure 7 is a line showing an example of a piston valve configured using the vibration damping pulp of the present invention. A cross-sectional side view, FIG. 1 shows another example of the present invention,
Figure (a) is a plan view of the disc valve used in this example,
The figure (1)) shows #! of the piston pulp of this example. Figures 2 and 1O are longitudinal side views similar to Figure 7, respectively. Figures 2 and 1O are vertical side views similar to Figure wJ7, which shows yet another example of the tube of the present invention. Figure @l1 is a diagram of the action characteristics of the valve according to the present invention. . l...inner cylinder, λ...outer cylinder, 3...piston, da...
...Piston rod! , 6... cylinder chamber, 7...
・Reservoir chamber, L... Piston pulp (vibration damping valve), R... Bottom pulp (vibration damping valve), io
, io'...retainer, 10a...orifice,
lOb...Through hole, "//. II'...Spring, 12./2'...Orifice plate, /2&, /ko'a...Slit, /3,13'
...Disc valve, /Ja...Slit. Figure 1 Figure 4 Ql I! x2 [Illustrated → Figure 8 (a) (b Figure 9 Figure 1O Figure 11

Claims (1)

[Claims] 1. By providing a disk valve-type vibration damping pulp and deforming the disk valve according to the pressure difference between the front and rear of the pulp, and controlling the working fluid according to the pressure difference, an electric flow pipe is operated. In the shock absorber having a vibration damping function 1, the disc valve is constituted by a disc spring, and the disc spring t is attached in a pre-deformed state so as to provide a constant load during the deformation. Vibration damping pulp for shock absorbers. 2. The vibration damping pulp for a shock absorber according to claim 1gg1, wherein the height of the disc spring in its free state is 0 times its thickness. 3. Claim 1, wherein the disc spring has a slit on its inner peripheral edge and also serves as an orifice plate! a
Vibration damping pulp for a shock absorber according to item 11 or 2. 4. The vibration damping pulp for a shock absorber according to any one of claims 1 to 3, wherein several disc spring tubes/sets are stacked one on top of the other.