JPH02195043A - Torsional damper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is directed to a torsion device that is attached to a rotating shaft such as the crankshaft of an engine to absorb torsional vibrations of the rotating shaft and to control the amplitude of the torsional vibrations so that the amplitude of the torsional vibrations does not increase. This is related to a national damper.

[Conventional technology]

In engines, especially diesel engines, complex torsional vibrations occur in the crankshaft due to the reciprocating movement of the piston, the unbalance of the piston crank mechanism, etc.
A torsional damper is provided on the crankshaft to absorb this torsional vibration and control the amplitude of the torsional vibration from increasing.

This torsional damper is constructed between - an inner annular rigid body attached to a rotating shaft such as a crankshaft within a shell, an outer annular rigid body as a damper mass disposed outside of the inner annular rigid body, and both groove-shaped rigid bodies. It is composed of an elastic member such as rubber that is interposed and bonded to the damper, and torsional vibrations are absorbed by this elastic member and an outer annular rigid body serving as a damper mass.

In such torsional dampers, nitrile-butadiene rubber (NBR), butyl rubber, or chlorinated butyl rubber (Utility Model Application Publication No. 59-1854) has conventionally been used as an elastic member.
46 Publication) etc. were used.

[Problem to be solved by the invention]

However, in torsional dampers that use conventional rubber as the elastic member, the vibration absorption characteristics have a large temperature dependence, and as the temperature of the torsional damper increases, the vibration absorption characteristics rapidly decrease. There is. Further, the heat resistance of the elastic member is insufficient, and when used at a high temperature of 150° C. or higher, thermal deterioration occurs, resulting in a shortened service life.

In particular, in recent years, engines have tended to have higher output and higher rotation speeds, and the temperature of the torsional damper has also increased.
The emergence of a torsional damper with low temperature dependence of its vibration absorption properties, whose vibration absorption properties do not deteriorate even under high temperatures, excellent heat resistance, and good durability under high temperatures has been awaited.

Therefore, an object of the present invention is to provide a torsional damper that has excellent vibration absorption properties and heat resistance, does not deteriorate in vibration absorption properties even under high temperatures, and can sufficiently cope with high engine output and high rotation speed. There is a particular thing.

[Means to solve the problem]

As a result of intensive studies to achieve the above object, the present inventors discovered that a phenyl group-containing silicone rubber could be used as the elastic member, and completed the present invention.

That is, the torsional damper of the present invention includes an inner annular rigid body attached to a rotating shaft, an outer annular rigid body disposed outside the inner annular rigid body, and an interposed adhesive bond between both groove-shaped rigid bodies. The elastic member is made of phenyl group-containing silicone rubber.

[For production]

In the torsional damper of the present invention, the inner annular rigid body is fixed to the tip of a rotating shaft such as a crankshaft, and torsional vibration is absorbed by the elastic member and the outer annular rigid body as a damper mass, and the amplitude of the torsional vibration is reduced. Control it so it doesn't get too big.

In this case, in the torsional damper of the present invention, phenyl group-containing silicone rubber is used as the elastic member. Due to its molecular structure, phenyl group-containing silicone rubber has large intramolecular friction due to steric hindrance of the phenyl group, and therefore has excellent vibration absorption properties. Moreover, since the phenyl group itself has no polarity, there is little deterioration in vibration absorption properties at high temperatures and physical properties such as tensile strength and elongation at break due to thermal deterioration. Although phenyl group-containing silicone rubber has various physical properties such as vibration absorption properties and tensile strength that are inferior to conventional rubber elastic members at low temperatures, these physical properties do not deteriorate much even at high temperatures. Therefore, a torsional damper using phenyl group-containing silicone rubber as an elastic member will
It exhibits better vibration absorption characteristics and durability than those using conventional rubber elastic members.

〔Example〕

Embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing one embodiment of the torsional damper of the present invention, in which 1 is an inner annular rigid body attached to the end of a rotating shaft (not shown) such as a crankshaft, 2 is an inner annular rigid body An outer annular rigid body 3 serving as a damper mass is disposed concentrically outside the rigid body 1, and 3 is an elastic member interposed and bonded between both groove-shaped rigid bodies 1.2. 4 is a sleeve provided between the inner annular rigid body 2 and the elastic member 3, but this sleeve 4 may be omitted.

The outer annular rigid body 2 also serves as a boob, has a groove on its outer periphery, wraps a V-belt around it, and is configured to transmit the driving force from the crankshaft to the succeeding member via the V-belt. can do.

The elastic member 3 is made of phenyl group-containing silicone rubber, and preferably silicone rubber represented by the following general formula is used.

(However, each mSn is an integer of 1 or more.

Here, the phenyl group-containing siloxane unit (represented by m) and the dimethylsiloxane unit (represented by n) may be randomly arranged in the rubber molecule.

In particular, it is preferable that the content of phenyl groups is 3.5 mol% or more, and when it is 3.5 mol% or more, tan δ, which indicates dynamic viscoelastic properties, becomes high and vibration absorption properties are improved.

There is no particular restriction on the upper limit, but if it is too large, the effect of improving vibration absorption properties will be reduced, so it is preferably about 8 mol % or less.

Phenyl group-containing silicone rubber is usually blended with a vulcanization aid, a vulcanization regulator, a reinforcing agent, a plasticizer, etc.
Vulcanization treatment at 0°C for 5 to 20 minutes, and further 180 to 210
Secondary vulcanization is carried out at 4 to 16 hours.

The adhesion between the right phenyl group-containing silicone rubber, the inner annular rigid body 1 (or the sleeve 4 if necessary), and the outer annular rigid body 2 is achieved by vulcanization and vulcanization using an adhesive such as a silane coupling agent. Do it at the same time.

In the torsional damper of the present invention, rotational force from a rotating shaft such as a crankshaft is transmitted to subsequent members via the inner annular rigid body 1, the elastic member 3, and the outer annular rigid body 2 as a damper mass. It has become. Further, the elastic member 3 and the outer annular rigid body 2 absorb torsional vibrations of a rotating shaft such as a crankshaft, and control the amplitude of the torsional vibrations so as not to increase.

The present invention will be explained in more detail by the following specific examples.

Example 1 In a phenyl group-containing silicone rubber represented by the following general formula, tan δ of the silicone rubber was determined when the phenyl group content was varied from 0 to 8 mol%. The additives added to each silicone rubber sample were as follows based on 100 parts by weight of silicone rubber.

Reinforcing agent (silica) 53 parts by weight Plasticizer 11 parts by weight vulcanizing agent
A test sample was prepared by vulcanizing 0.6 parts by weight of a silicone rubber compound having the above composition at 170°C for 10 minutes, and then secondary vulcanization at 200°C for 4 hours. Tan δ of each sample at room temperature! Measurement was performed under OHZ vibration conditions. The results are shown in Figure 2.

As is clear from FIG. 2, the phenyl group content is 3.
It can be seen that when the amount exceeds 5 mol %, tan δ increases rapidly and the damping performance of the silicone rubber increases.

Example 2 A crosslinked phenyl group-containing silicone rubber (Phenyl M, containing 115 J%, sample A) and a silicone rubber not containing phenyl groups (sample A) were manufactured under the same conditions as Example 1.
Sample B) and acrylonitrile-butadiene rubber (
Sample C) (NBR) and tan
The temperature dependence of δ was measured. The results are shown in Figure 3. The phenyl group-containing silicone rubber (sample A) used in the present invention has extremely small temperature dependence of tan δ, and especially at high temperatures, the double-acting absorption property is higher than that of NBR (sample C) and the phenyl group-free silicone rubber (sample B). ) is found to be better than

The tensile strength of each sample was also measured. Fourth
The figure is a graph showing the temperature dependence of tensile strength for each sample. The phenyl group-containing silicone rubber used in the present invention (sample A) has a small temperature dependence of tensile strength, and at high temperatures, It can be seen that the tensile strength is higher than that of Sample B and NBR (Sample C).

Furthermore, in order to evaluate the heat resistance of each sample,
And the rate of change in elongation at break over time at 175°C was measured. The results are shown in Figure 5. From FIG. 5, the rate of change in elongation at break of the phenyl group-containing silicone rubber (sample A) used in the present invention is extremely small (similar to sample B, NBR
It can be seen that the heat resistance is far superior to that of (Sample C).

Example 3 Phenyl group-containing silicone rubber of Example 2 (Sample A
), silicone rubber containing no phenyl groups (sample B) and acrylotryl-butadiene rubber (sample C).
), we fabricated torsional dampers with the structure shown in Figure 1, and in order to evaluate the dynamic characteristics during resonance,
℃, tan δ at the resonance point, and resonance magnification were measured. The results are shown in Table 1 below.

Table 1 tan δ Resonance magnification Sample A OJ5 3.0 Sample B O, 176, 1 Sample CO, 234, 0 From the above results, the phenyl group-containing silicone rubber of the present invention (Sample A) has good damping characteristics. I understand.

Example 4 Regarding Sample A and Sample C of Example 2, in order to evaluate the temperature dependence of the resonance frequency, the rate of change in the resonance frequency at each temperature was measured. Note that the resonance frequency at 60° C. was taken as the reference (0). The results are shown in Table 2.

Table 2 Temperature Sample A Sample CO℃
+21% +37%30℃
+7% +14%90℃ -3
% -8%120℃ -5%
The results of −13% or more indicate that the phenyl group-containing silicone rubber of the present invention (sample A) has a small change in resonance frequency.

[Effects of the Invention] In the torsional damper of the present invention, the elastic member made of phenyl group-containing silicone rubber has low temperature dependence of dynamic viscoelastic properties and tensile strength, and has excellent heat resistance and high temperature durability. , excellent vibration absorption properties and heat resistance, 15
The vibration absorption properties do not deteriorate even at high temperatures of 0° C. or higher, and can sufficiently support higher engine output and higher rotation speeds.

[Brief explanation of the drawing]

1st r! ! J is a sectional view showing an example of the torsional damper of the present invention, FIG. 2 is a graph showing the relationship between the phenyl group content and tan δ of phenyl group-containing silicone rubber, and FIG. 3 is a graph showing the relationship between the phenyl group content and tan δ of the phenyl group-containing silicone rubber. Fig. 4 is a graph showing the temperature dependence of the tensile strength of each sample, and Fig. 5 is a graph showing the change in elongation at break of each sample over time. It is. 1... Inner annular rigid body 2 - Outer annular rigid body 3 - Elastic member Applicant: Honda Motor Co., Ltd. Representative Patent attorney Tachibana Takaishi Phenyl group content (MO base %) 3rd Figure Temperature (0C) Temperature (0C)

Claims (2)

[Claims] (1) A tow consisting of an inner annular rigid body attached to the rotating shaft, an outer annular rigid body disposed outside the inner annular rigid body, and an elastic member interposed and bonded between both annular rigid bodies. 1. A torsional damper, wherein the elastic member is made of phenyl group-containing silicone rubber. (2) In the torsional damper according to claim 1,
A torsional damper characterized in that the phenyl group-containing silicone rubber is represented by the following general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (where m and n are each integers of 1 or more).