JPH051723A - Synchronizer ring - Google Patents

Abstract

PURPOSE:To provide a synchronizer ring which has an excellent friction characteristic and a sufficient wear resistance without the generation of a strength shortage and no requirement of the grinding process and/or the cutting process of a thermal spray film and also has quality stabilized. CONSTITUTION:A thermal spray film 3 stays on a contact sliding surface with an opposite member, in a synchronizer ring which can carry out the synchronous slide with the rotating opposite member and the separation from the opposite member. This flame spray film 3 is a molybdenum flame spray film or a molybdenum alloy flame spray film whose ceramics content is 5-30weight% and surface roughness(Rz) is 20-60mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synchronizer ring, and more specifically, it has excellent friction characteristics and sufficient wear resistance and durability, and does not require grinding or cutting of a sprayed film. Moreover, it relates to a synchronizer ring with stable quality.

[0002]

2. Description of the Related Art For example, a synchronous mesh type gear transmission has conventionally used a synchronizer ring.

This syncronizer ring is a friction ring for performing synchronous sliding with a rotating mating member, for example, a tapered cone, and for separating from the tapered cone, and the peripheral speeds of two gears meshing with each other are made uniform speeds. Make an important move to do. As its structure, as shown in FIG. 4, a large number of tooth profiles 100 that mesh with the mating member are provided at the outermost peripheral portion at predetermined intervals, and a frictional force is applied to the inner peripheral surface 101 that contacts the tapered cone. Is provided with a ring-shaped groove 102, and a vertical groove 103 for releasing the lubricating oil is formed so as to be orthogonal to the ring-shaped groove 102, and a synchronizer key is fitted on the outer peripheral surface. It is known that the key groove 104 is formed, and the forming material is generally brass (Cu-Zn alloy).
Was used.

[0004] For example, in a synchronizer ring which may be formed in such a structure, generally, the mechanical strength and precision are high, and in addition, the inner peripheral surface in contact with the mating member has excellent friction characteristics. It is required to have sufficient wear resistance. In particular, in the field of automobile transmissions, in addition to reliable operability in recent years due to higher quality and higher performance of missions, a feeling of luxury and sporty feeling are required for the operation feeling. A synchronizer ring having further improved wear resistance is desired.

Therefore, various types of synchronizer rings have been studied in which the frictional characteristics and wear resistance of the inner peripheral surface are improved as compared with the conventional synchronizer rings using brass (Cu-Zn alloy) as a forming material. ..

Specifically, a synchronizer ring (Japanese Patent Publication No. 46-15043) in which a layer in which a metal, a ceramic and an oxide are uniformly mixed and which are fused to each other is formed on the inner peripheral surface by a thermal spraying method. (See the official gazette). Further, as a method that can be used for manufacturing a synchronizer ring, for example, a friction lining made of a sintered powder containing 80% by weight of metal component powder and 20% by weight of non-metal component powder is applied to the inner peripheral surface by a flame injection method. A method for manufacturing a friction ring to be formed (West German Patent No. 3705661) is also known.

[0007]

However, a layer in which a metal, a ceramic and an oxide are uniformly mixed and which are fused together and formed on the inner peripheral surface by a thermal spraying method, or 80% by weight of metal component powder A conventional synchronizer such as that obtained by adopting a method for producing a friction ring in which a friction lining made of a sintered powder containing 20% by weight of non-metal component powder is formed on the inner peripheral surface by a flame injection method. The ring has not yet reached the required frictional properties and wear resistance. There is also a problem that the strength is insufficient due to insufficient diffusion of each metal component, and the quality becomes unstable due to variations in the material of the thermal spray coating. In addition, incompletely melted particles in the flame, or scattered / warped particles, etc. may often be caught in the surface layer of the sprayed film, and the adhesion of these particles roughens the surface. It becomes easy to change to
There is also a problem that the adhered particles may fall off, which may cause wear of various parts of the mission system. On the other hand, the surface of the sprayed film was also subjected to grinding or cutting for the purpose of reducing the surface roughness of the sprayed film.
When such grinding or cutting is performed, there are drawbacks that the processing cost is high and the raw material is wasted in the stock removal due to the grinding or cutting.

The present invention has been made based on the above circumstances, and an object of the present invention is to have excellent friction characteristics and sufficient wear resistance, without causing insufficient strength, and for thermal spraying. The purpose of the present invention is to provide a synchronizer ring which does not require film grinding or cutting and has stable quality.

[0009]

The structure of the present invention for attaining the above-mentioned object is to provide a contact with a mating member in a synchronizer ring that performs synchronous sliding with the mating member that rotates and disengages from the mating member. The sliding surface has a sprayed film, and the sprayed film is a molybdenum sprayed film or a molybdenum alloy sprayed film having a ceramic content of 5 to 30% by weight and a surface roughness (R _z ) of 20 to 60 μm. It is a synchronizer ring.

The synchronizer ring of the present invention will be described below with reference to the drawings. FIG. 1 is a partial cross-sectional view schematically showing an example of the synchronizer ring of the present invention. In FIG. 1, the synchronizer ring 1 is composed of a ring body 2 and a sprayed film 3, and the sprayed film 3 is formed on the inner peripheral surface of the ring body 2.

The ring body 2 is made of, for example, a Cu--Zn system,
Cu-Ni system, Cu-Al system, Cu-Sn system, Cu-S
Various copper alloys such as i type; Cr steel, Cr-Mo steel, Ni-C
It is formed of various iron-based alloys such as r steel, Ni-Cr-Mo steel, Mn steel, and Mn-Cr steel.

The sprayed film 3 contains molybdenum (Mo) or molybdenum (Mo) alloy. Here, examples of the molybdenum (Mo) alloy include those containing Mo as a main component and elements such as Cr, Si, B, C, Fe, and Ni.

The hardness (Hv) of such Mo or Mo alloy is usually 250 to 450, preferably 300.
It has a soft phase in the range of up to 400, and 70% or more, preferably 75% or more of the surface area is occupied by the soft phase.

Here, the above-mentioned soft phase has an effect of generating microscopic plastic flow at the time of contact with a mating member to enhance frictional characteristics, in particular, dynamic friction coefficient and improve synchronism of the synchronizer ring. Therefore, if the proportion of the soft phase on at least the surface of the sprayed film 3 is less than 70%,
The effect of increasing the dynamic friction coefficient may not be sufficiently exhibited. Further, if the hardness (Hv) is less than 250, the microscopic plastic flow may proceed excessively at the time of contact with the mating member, resulting in excessive self-wear. On the other hand, hardness (Hv) is 45
When it exceeds 0, the microscopic plastic flow does not proceed sufficiently at the time of contact with the mating member, and a sufficient dynamic friction coefficient may not be obtained.

Ceramic particles in the sprayed film 3 are 5 to 3
0% by weight, preferably 10 to 20% by weight evenly
It is distributed. Here, as this ceramic,
Si, B, Al, Mn, Cu, Co, Ni, Na, C
Examples include oxides, carbides, nitrides, etc. of r, W, Ti, V, etc.
You can More specifically, for example, SiO₂, Ni
O, MnO, CuO, CoO, Na ₂O, Al₂O₃,
B₂O₃, SiC, Cr₂C₃, Si₃N_Four, Mo
₂N, CrN, WC, TiN, VC, etc., or Si
O₂, NiO, MnO₂, CuO, CoO, Na₂O,
Al₂O₃, B₂O₃, RO₂(However, R is a rare earth element
Represents a prime. Same in the examples. ), K₂O, MgO,
ZnO₂Composite ceramic particles composed of a plurality of
You can

The sprayed film 3 in which the ceramic particles are uniformly dispersed in the above proportion has an increased dynamic friction coefficient and has good friction characteristics, but if the content of the ceramic particles is less than 5% by weight, Excessive self-wear may reduce wear resistance. On the other hand, if the content of the ceramic particles exceeds 30% by weight, the wear of the mating cone may become excessive.

The hardness (Hv) of the sprayed film 3 in which the ceramic particles are uniformly dispersed in the above proportion is usually 350 to 6.
50. If this hardness (Hv) is less than 350,
The wear resistance may be insufficient. On the other hand, if the hardness (Hv) exceeds 650, the wear of the mating cone increases and the sprayed film 3 may become brittle.

Mating member (mating cone) in the sprayed film 3
The surface roughness R _z of the sliding surface of is usually 20 to 60 μm,
It is preferably in the range of 30 to 55 μm. When the surface roughness R _z is in the above range, wear of the mating member (mating cone) can be further reduced, and excellent deterioration / variation of frictional characteristics (aging, rotational speed / pressure / oil temperature) can be achieved. Change due to the influence of the above) is suppressed and excellent friction characteristics are maintained for a long period of time.

In order to set the surface roughness R _z within the above range, for example, the surface of the sprayed film 3 (sliding surface with the mating cone).
Brushing may be applied to. For this brushing treatment, a metal or non-metal brush containing hard particles having a hardness (Hv) of 1000 or more is preferably used. More specifically, for example, SiC abrasive grains [hardness (H
v) 2600] -containing nylon brushes and the like.

If the surface roughness R _z is less than 20 μm, it takes a long time to perform the above-mentioned brushing process, resulting in an increase in manufacturing cost. On the other hand, when it exceeds 60 μm, the above-described effect of suppressing wear of the mating cone, deterioration and fluctuation of frictional characteristics may not be obtained in some cases.

The sprayed film 3 contains pores, and these pores have a function or function of breaking an oil film and storing oil. That is, the holes increase the dynamic friction coefficient in combination with the operation (pressurization and negative pressure on the oil film) between the synchronizer ring and the mating cone to improve synchronism and reduce the static friction coefficient. The effect of improving detachability is achieved.

The ratio of the above-mentioned voids on the surface of the sprayed film 3, that is, the surface porosity is 5 to 30%, preferably 7 to.
25%. If the surface porosity is less than 5%, the effect of breaking the oil film becomes insufficient, and the above-described effect of increasing the dynamic friction coefficient and reducing the static friction coefficient may not be sufficiently exhibited. On the other hand, when the surface porosity exceeds 30%,
This may lead to insufficient strength of the sprayed film 3.

The thickness of the sprayed film 3 is usually 70 to 200 μm.
m, preferably 90 to 120 μm. If this thickness is less than 70 μm, the amount of pores may be insufficient and the required frictional characteristics may not be obtained.
On the other hand, when the thickness exceeds 200 μm, the sprayed film 3 is likely to be peeled off from the ring body 2 and the durability may be lowered, and the manufacturing cost may be increased.

Such a synchronizer ring is manufactured, for example, as follows. That is, as a raw material powder, a mixed powder in which molybdenum (Mo) powder or molybdenum (Mo) alloy powder and the ceramic particles are uniformly mixed is used as the raw material powder on the inner peripheral surface of the ring main body 2 formed into a predetermined shape by a conventional method. To spray. As the thermal spraying method adopted at this time, for example, plasma spraying method, flame spraying method (powder method)
The plasma spraying method is particularly preferably used.
As the above-mentioned raw material powder, the one obtained by the atomization method, that is, the atomized powder is preferably used. This is because when the above raw material powder is atomized powder, each component is uniformly dispersed. Then, after forming the sprayed film 3 with a predetermined thickness on the inner peripheral surface of the ring body 2, the surface is finished by brushing so that the surface roughness (R _z ) of the sprayed film 3 is in the range of 20 to 60 μm. To do. The synchronizer ring manufactured in this manner has an increased dynamic friction coefficient and improved synchronism, and at the same time has a reduced static friction coefficient and excellent detachability, and also has sufficient wear resistance. There is.

[0025]

EXAMPLES Next, the present invention will be described more specifically by showing examples. (Example 1) On the inner peripheral surface (sliding surface with the taper cone) of the ring body made of high strength brass (JIS HBsC3 equivalent product),
150 mesh molybdenum alloy (63.8% Mo-
3.6% Cr-0.85% Si-0.68% B-0.1
A mixed powder obtained by adding ceramic particles (-250 mesh Cr ₂ C ₃ particles) at a ratio of 15% by weight to a raw material powder composed of 7% C-0.85% Fe-remaining Ni) powder (atomized powder). Was plasma sprayed to form a 100 μm thick molybdenum alloy sprayed film, which was used as a synchronizer ring material.

Then, using a nylon brush (wire diameter 0.6 mmφ) containing SiC abrasive grains [hardness (Hv) 2600] on the surface of the sprayed film formed on the synchronizer ring material, the surface of the sprayed film was used. The roughness (Rz) was finished to 55 μm to prepare a synchronizer ring.

With respect to this synchronizer ring, the peel strength, frictional characteristics and wear amount of the molybdenum alloy sprayed film were evaluated. The peeling strength, frictional characteristics and wear amount of the molybdenum alloy sprayed film were evaluated as follows.

Peel strength: Measured according to JIS H 8666 "Ceramic spray test method". Friction characteristics and wear amount: The friction coefficient and the wear amount were measured under the following conditions using a synchronizer ring simple wear tester having the configuration shown in FIG.

Test conditions: constant speed slip mode Pressing load: 80 kgf Rotational speed: 800 rpm Pressing time: 0.2 seconds Lubricating oil used: 75w-90 (80 ° C) Lubrication rate 0.6 liters / min Counterpart material: material; SCr420 [Surface hardness (Hv) 580] Shape: Cone taper Cone angle 6 ° 40 ″ Desorption frequency: 5000 times In the synchronizer ring single wear tester shown in FIG. 3, 10 is an electromagnetic valve, 11 is an air cylinder, 12 is a pressing load cell, 13 is a frictional load cell, 14 is a ball bush, 15 is a lubricating oil inlet, 20 is a synchronizer ring, 21 is a tapered cone, 16
Is an electromagnetic clutch, 17 is a flywheel, 18 is an AC servomotor, and the amount of wear is measured by the amount of subsidence of the wear amount measuring unit 19.

The composition of the molybdenum alloy sprayed film and the measurement results are shown in Tables 1 and 2.

[0031]

[Table 1]

[0032]

[Table 2] (Examples 2 to 7) Using the raw material powders having the compositions shown in Table 1, the ceramic addition rate, the thickness of the sprayed film, and the finished surface roughness (R _z ) of the sprayed film by the brushing treatment are shown in Table 1. Example 1 was repeated except that

The composition of the molybdenum alloy sprayed film and the measurement results are shown in Tables 1 and 2. (Comparative Example 1) In Example 1, a sprayed film of molybdenum alloy having a surface porosity of 5% by volume and a soft phase content of 70% by volume having a hardness (Hv) in the range of 250 to 450 is formed. At the same time, a synchronizer ring was prepared in the same manner as in Example 1 except that the surface of the sprayed coating was not brushed, and the synchronizer ring was evaluated.

The composition of the molybdenum alloy sprayed film and the measurement results are shown in Tables 1 and 2. (Comparative Example 2) The same procedure as in Example 1 was repeated except that a sprayed film having a surface porosity of 30% by volume was formed and the surface of the sprayed film was not brushed. A Nizer ring was prepared, and this synchronizer ring was evaluated.

The composition of the sprayed molybdenum alloy film and the measurement results are shown in Tables 1 and 2. (Comparative Example 3) The same procedure as in Example 1 was repeated except that in Example 1, a sprayed film having a surface porosity of 3% by volume was formed, and the surface of the sprayed film was not brushed. A Nizer ring was prepared, and this synchronizer ring was evaluated.

The composition of the sprayed molybdenum alloy film and the measurement results are shown in Tables 1 and 2. (Comparative Example 4) The same procedure as in Example 1 was repeated except that in Example 1, a sprayed film having a surface porosity of 35% by volume was formed and the surface of the sprayed film was not brushed. A Nizer ring was prepared, and this synchronizer ring was evaluated.

The composition of the molybdenum alloy sprayed film and the measurement results are shown in Tables 1 and 2. (Comparative Example 5) In Example 1, a sprayed film of molybdenum alloy having a surface porosity of 10 vol% and a soft phase content of 65 vol% with a hardness (Hv) in the range of 250 to 450 is formed. At the same time, a synchronizer ring was prepared in the same manner as in Example 1 except that the surface of the sprayed coating was not brushed, and the synchronizer ring was evaluated.

The compositions of the molybdenum alloy sprayed film and the measurement results are shown in Tables 1 and 2. (Comparative Example 6) Using the molybdenum alloy having the composition shown in Table 1, the surface porosity was 5% by volume and the hardness (Hv) was 250 to 450.
In the same manner as in Example 1, except that a sprayed film of molybdenum alloy having a soft phase content of 90% by volume in the range was formed and the surface of the sprayed film was not brushed. A ring was prepared, and this synchronizer ring was evaluated.

The composition of the molybdenum alloy sprayed film and the measurement results are shown in Tables 1 and 2. (Comparative Example 7) Instead of the raw material powder used in Example 1, Table 1
A synchronizer ring was produced in the same manner as in Example 1 except that the raw material powder having the composition shown in 1 was used and the ceramic addition rate was 35% by weight, and the synchronizer ring was evaluated.

The composition of the molybdenum alloy sprayed film and the measurement results are shown in Tables 1 and 2. (Comparative Example 8) Instead of the raw material powder used in Example 1, Table 1
A synchronizer ring was prepared in the same manner as in Example 1 except that the raw material powder having the composition shown in 1 was used, the ceramics addition rate was 3% by weight, and the sprayed film was not brushed. The ring was evaluated.

Tables 1 and 2 show the composition and measurement results of the molybdenum alloy sprayed film. (Study of Results) As is clear from Tables 1 and 2, the synchronizer rings of the examples have a higher dynamic friction coefficient than the synchronizer rings of the comparative examples, the friction characteristics are improved, and the wear amount is increased. It was confirmed that the heat resistance was reduced and the abrasion resistance was excellent, and that the sprayed film had sufficient peeling strength and the strength was not insufficient. Also,
The synchronizer rings of the examples had stable quality. Furthermore, when the relationship between the surface roughness and the coefficient of dynamic friction was examined for Example 1, Example 4, and Example 5, FIG.
And the surface roughness (R _z ) is particularly 2
It was confirmed that when the thickness was in the range of 0 to 60 μm, the dynamic friction coefficient did not decrease so much and the deterioration of synchronism was suppressed.

[0042]

EFFECTS OF THE INVENTION According to the present invention, because of the above-mentioned constitution, the friction characteristics are improved, the synchronism with the mating cone and the releasability are excellent, and the abrasion resistance and durability are sufficient. It is possible to provide a synchronizer ring that does not cause insufficient strength, does not require grinding or cutting of the sprayed film, and has stable quality.

[Brief description of drawings]

FIG. 1 is a partial sectional view schematically showing an example of a synchronizer ring of the present invention.

FIG. 2 is a graph showing the relationship between the surface roughness and the coefficient of dynamic friction in the synchronizer ring of the present invention.

FIG. 3 is an explanatory view showing an outline of a synchronizer ring single-body wear tester used in Examples.

FIG. 4 is a perspective view showing an example of a conventional synchronizer ring.

[Explanation of symbols]

 1 ... Synchronizer ring 2 ... Ring body 3 ... Copper alloy sprayed film

Claims (1)

Claim: What is claimed is: 1. A synchronizer ring that performs synchronous sliding with a rotating mating member and disengages from the mating member, wherein a spraying film is provided on a contact sliding surface with the mating member. The film has a ceramic content of 5 to 30% by weight and a surface roughness (R
_z ) A synchronizer ring, which is a molybdenum sprayed film or a molybdenum alloy sprayed film having a thickness of 20 to 60 μm.