JPH0799179B2 - Synchronizer ring - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a synchronizer ring used in a synchronizing device of an automobile or the like, and more particularly to a synchronizer ring having a pad portion made of a friction material on an inner peripheral portion thereof. In a gear transmission that shifts gears by meshing gears, if the peripheral speed of the teeth of the gear does not match the peripheral speed of the teeth of the other gear, noise may be generated at the speed and damage to the teeth may occur. . The synchronizer, when engaging the gears, with the teeth of one gear,
It is used for synchronizing the teeth of the other gear with each other so that the peripheral speeds of the both gears coincide with each other. The synchronizer ring is used as a main component of this synchronizer.

[Prior Art] Generally, in a synchronizer ring, the inner taper cone portion of the inner peripheral portion of the synchronizer ring is brought into frictional contact with the outer taper portion of the outer peripheral portion of the transmission gear, and the friction generated between both taper cone portions is thereby caused. A predetermined rotation synchronizing action is achieved by the force. This synchronizer ring is used under extremely severe conditions due to its small size, light weight, and high speed rotation. As a result, the surface pressure of the inner taper cone portion of the inner peripheral portion of the synchronizer ring increases. Therefore, when an oil groove is formed on the inner taper cone of the inner circumference of the synchronizer ring, wear of the top of the oil groove is promoted, and in extreme cases, the top of the oil groove is plastic. It may cause deformation. Therefore, the contact area between the inner taper cone portion of the synchronizer ring and the outer taper cone portion of the transmission gear gradually increases, and the oil film formed between the surfaces of both taper cone portions becomes remarkable. As a result, the coefficient of friction between the surfaces of the two tapered cone portions is significantly reduced, the time required for the rotation synchronizing action becomes long, and gear squealing during shifting occurs.

Therefore, recently, JP-A-60-227021 and JP-A-60-16
A synchronizer ring according to Japanese Patent No. 7234 is provided. The former no synchronizer ring has a sprayed layer formed on the inner tapered cone portion. The latter is one in which the top land surface of the oil groove formed on the surface of the tapered cone portion has a step and is divided into two or more regions. However, it was still insufficient to solve the above problems.

Further, as the synchronizer ring, there is also provided one in which a pad portion made of a friction material is fixed to the inner taper cone portion of the inner peripheral portion. It is also conceivable to form an oil groove in this pad portion. The synchronizer ring in which the oil groove is formed in the pad portion compensates for the lack of the lubricating oil oozing out from the friction material itself with the lubricating oil held in the oil groove to promote cooling of the friction surface. However, in the synchronizer ring provided with this pad portion, although the oil groove effectively acts to retain the lubricating oil, the pad portion itself made of friction material is generally extremely thin and therefore the pad portion is soft, and therefore the oil groove is processed. Is difficult. Even if the oil groove is formed in the pad portion by cutting, it is difficult to remove the chips generated by the cutting, and the chips may mix into the lubricating oil, resulting in problems such as clogging of the lubrication path. It is also possible to form the oil groove by pressing, but in this case, the porous structure originally possessed by the friction material is crushed by pressing, and the friction material forming the pad is impregnated with lubricating oil. Less likely to take advantage of it.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned circumstances, and makes it possible to maintain the lubricating oil well and stabilize the friction coefficient for a long period of time without forming an oil groove in the pad portion. The aim is to provide a synchronizer ring with improved durability.

[Means for Solving Problems] A synchronizer ring according to the present invention includes a synchronizer ring body extending in a circumferential direction having an inner tapered cone portion on an inner peripheral portion, and an inner peripheral surface of an inner tapered cone portion of the synchronizer ring body. When the pad area is 100%, the pad area has a high porosity with a higher porosity than the rest of the pad area. ,
The feature is that the area of the high pores is set to 10 to 40%. The area means the area in the circumferential direction to rub against the mating material.

The synchronizer ring body has an inner tapered cone portion on the inner peripheral portion. The inner taper cone portion is a portion that is in sliding contact with the outer taper cone portion of the mating member of the synchronizer. The synchronizer ring main body is usually a continuous endless annular body, but it may be partially cut out depending on the case. The mating member is usually the outer taper cone portion of the transmission gear. If the synchronizer is a BorgWarner type,
Splines are formed on the outer peripheral surface of the synchronizer ring body. As the base material of the synchronizer ring body, the same material as the conventional one can be used. For example, a copper alloy, an iron-based alloy or the like can be used. As the copper alloy, bronze type and brass type can be used.

The pad portion is made of a friction material fixed to the inner peripheral surface of the inner tapered cone portion of the synchronizer ring body. The friction material forming the pad portion is a paper-like member obtained by adding an inorganic filler as a friction characteristic improving material to pulp, or the paper-like member is impregnated with a thermosetting resin such as a melamine resin or a modified resin and cured. Different materials can be used.

The pad portion is characterized by having a high porosity portion having a higher porosity than other portions of the pad portion. Pad area 10
At 0%, the area of high pores is 10-40%.

The high porosity portion preferably has a porosity of 45 to 75%.
In this case, the pad portion other than the high porosity portion has a porosity of 10
About 16% is preferable.

Here, the porosity refers to the ratio of the volume of the pores to the volume of the pad portion.

A plurality of high porosity portions can be arranged in parallel with each other substantially in parallel with the axial center direction of the synchronizer ring body, as will be illustrated in Examples described later. In this case, it is preferable that the high porosity portions are arranged in parallel at uniform intervals. Further, the high-pore portion may be formed by dispersing a plurality of high-pore portions in a lump form, as illustrated in Examples described later.

The pad part includes a step of forming a primary pad part composed of a base material made of a friction material and a volatilizing material dispersed in the base material, and a heat treatment of the primary pad part to evaporate the volatilizing material in the primary pad part. By doing so, it can be manufactured from the step of forming a high pore portion. As the volatilizing material, at least one kind of naphthalene, anthracene, anthraquinone, phenanthrene and camphor can be used. In this case, the volatilizing material may be used alone or in combination of plural kinds.

In a special case, the pad part is formed by a step of forming a primary pad part containing a water solvent composed of a water-soluble inorganic compound such as calcium sulfate, sodium chloride, magnesium chloride, potassium chloride, and the water solution of the primary pad part. It can also be formed by a step of melting and forming a high pore portion. In a special example, the pad portion is manufactured by a step of forming a primary pad portion including a foam material such as ammonium carbonate and sodium bicarbonate, and a step of foaming the foam material to form a high pore portion. You can also do it.

The thickness of the pad portion is appropriately set according to the type of synchronizer ring, but generally 0.2 to 0.8 mm is preferable.

[Operation] Since the pad portion of the synchronizer ring according to the present invention is made of a friction material, it can be impregnated with lubricating oil, and the high porosity portion of the pad portion has a higher porosity than that of the surroundings. Lubricating oil can be easily lubricated into the pores of the high pores. Therefore, the cooling characteristics of the friction surface of the pad portion is improved, the coefficient of friction between the inner tapered cone portion of the synchronizer ring and the outer tapered cone portion of the mating member, despite the wear of the friction material forming the pad portion, Always maintained in proper condition.

[Effect of the Invention] According to the synchronizer ring of the present invention, the pad portion provided on the inner tapered cone portion of the synchronizer ring has a structure having high pores. Therefore, the friction coefficient between the synchronizer ring and the friction between the mating member can be maintained at an appropriate value.

Further, according to the synchronizer ring of the present invention, since the pad portion does not have an oil groove as in the conventional case, the pad portion is always in frictional contact with a mating member such as the outer taper cone portion of the transmission gear on a flat surface. Even if the friction material of the part wears,
A stable friction coefficient can always be secured. Therefore, the synchronizing device can exhibit a stable rotation synchronizing action for a long period of time.

[Embodiment] FIG. 1 shows an embodiment according to the present invention. This embodiment is applied to a synchronizer ring of a synchronizing device used in an automobile.

The synchronizer ring according to the present embodiment is a synchronizer ring body 1 having an inner tapered cone portion 10 on the inner peripheral portion.
And the inner taper cone of the synchronizer ring body 1
The pad portion 2 is fixed to the inner peripheral surface of 10.

The base material of the synchronizer ring body 1 is steel (JIS
-S45C), with a splined portion on the outer periphery.
With 11. The pad portion 2 is fixed by applying an adhesive agent to the inner taper cone portion 10, adhering the pad portion 2 with the adhesive agent, and pressing the pad portion 2 while heating.

In this embodiment, the pad portion 2 made of a friction material comprises 100 parts by weight of linter pulp and diatomaceous earth 40 as an inorganic filler.
It is formed by making a water-soluble dispersion liquid by adding 30 parts by weight of cashew dust as an organic filler. In this embodiment, the pad portion 2 has a high porosity portion 20 having a higher porosity than other portions of the pad portion 2. High pores 20
Has a porosity of about 50 to 55%. The high-pore portion 20 is the first
As shown in the figure, a plurality of circles are formed and are dispersed substantially uniformly. In this example, the high-pore portion 20 has more pores than other portions by applying heat to the pad portion 2 to vaporize and evaporate the volatile material composed of naphthalene in that portion, that is, by performing heat shear treatment. Is formed. As the heat shear treatment, in this embodiment, 500
This is performed by pressing a hot plate heated to about ℃ to 700 ℃ against the pad portion 2 made of a friction material as a base material for about 1 minute. The porosity of the portion of the pad portion 2 other than the high porosity portion 20 is about 25 to 30%. FIG. 3 shows an enlarged cross-sectional view of the main part.

Another embodiment of the present invention is shown in FIG. This embodiment is basically the same as the above-mentioned embodiment. However, high porosity 20
Is the synchronizer ring body 1 as shown in FIG.
A plurality of them are arranged in parallel at substantially uniform intervals in parallel with the axial direction of the. The porosity of this high pore portion 20 is about 50 to 55%,
The porosity of the pad portion 2 other than the high porosity portion 20 is about 25 to 30%.

In the synchronizer ring according to each of the above examples,
The area ratio between the high porosity portion 20 having a large porosity and the portion having a small porosity is
It is always secured at an almost constant value. Therefore, the coefficient of friction between both tapered cone portions is kept substantially constant. Therefore, when applied to a synchronizing device of an automobile, a stable rotation synchronizing action can be achieved for a long period of time.

Next, the operation of the synchronizing device will be described by taking the case of application to a synchronizing device of an automobile as an example. Here, in FIG. 4, 5S is an output shaft, 1S is an output shaft 5S and a roller bearing.
A transmission gear having a spline 2S rotatably attached via 6S, and 15S is a clutch hub attached to the output shaft 5S. On the outside of the clutch hub 15S, the hub sleeve 1
6S is spline-fitted so that it can slide in the axial direction of the output shaft 5S. This example synchronizer ring 1
Is interposed between the transmission gear 1S and the hub sleeve 16S.

Then, as shown in FIG. 6 (A), when the sleeve 16S moves in the direction of arrow X, the synchronizer key 17S also moves. Then, since the synchronizer key 17S hits the synchronizer ring 1 and pushes it, the pad portion 2 of the synchronizer ring 1 is pressed against the outer tapered cone portion 12S of the gear 1S, and the gear 1S starts to rotate due to the friction generated at this time.

When the sleeve 16S further moves in the direction of arrow X as shown in FIG. 6 (B), the synchronizer key 17S moves the sleeve 1
The synchronizer ring 1 is pushed further strongly from the inner surface of the 6S, and the tip of the spline 18S on the inner surface of the sleeve 16S hits the tip of the spline 11 of the synchronizer ring 1S, where the movement of the sleeve 16S is the synchronizer ring 1 Blocked by. Therefore, the sleeve 16S strongly pushes the synchronizer ring 1. Therefore, the pad portion 2 of the synchronizer ring 1 is the outer taper cone portion 12S.
A large frictional force is generated when the sleeve 16S and the gear 1S rotate at the same circumferential speed. When the synchronization is completed and the relative speed difference between the sleeve 16S and the gear 1S is eliminated, the sleeve 16S is further moved in the direction of arrow x, as shown in FIG. 6 (C).
The gear shift ends when the 16S spline 18S meshes with the gear 1S spline 2S.

Next, the experimental results of the synchronizer ring shown in FIG. 1 will be described. In this case, the vertical axis represents the coefficient of friction between the outer taper cone portion 12S of the gear 1S and the inner taper cone portion 10 of the synchronizer ring 1, and the horizontal axis represents the number of frictional contacts between the two taper cone portions 12S and 10 or the number of rotation synchronization operations. The results of the use durability test of the synchronizer having the synchronizer ring of Example 1 are shown. Similarly, an experiment was performed on a comparative example. The results are shown in FIG.

A characteristic curve A according to this embodiment is shown in FIG.
In this case, the area ratio between the high porosity portion 20 having a large porosity and the portion having a low porosity is 30:70. As shown by the characteristic curve A, even if the number of frictional contacts increased to 500 × 10 ² times, the friction coefficient was secured at around 0.12, and there was almost no decrease in the friction coefficient. It is considered that this is because the pores of the high pore portion 20 are likely to be impregnated with the lubricating oil and the cooling characteristics of the friction surface are improved.

No. 1 to No. 3 as comparative examples are those in which the pad portion is fixed to the inner taper control portion of the synchronizer ring as in the present embodiment, but No. 1 has a small porosity (porosity 25
(~ 30%) was set to 100%, i.e. no heat shear treatment was performed. No. 2 has a large porosity (porosity 50-55
%) That is, the portion having a relatively small friction coefficient was set to 100%, that is, the heat shear treatment was performed as a whole. In No. 3, the proportions of the high porosity portion, which is the high porosity portion and the low porosity portion, are set to 50% and 50%, respectively. No. 4 is a copper-based synchronizer ring that has been commonly used in the past, and has a plurality of oil grooves formed in the tapered cone portion of its inner peripheral portion.

As is clear from FIG. 5, in No. 4, No. 2 and No. 3 as well, when the number of frictional contacts increased, the friction coefficient between both tapered cone surfaces was increased as compared with the characteristic curve A according to this example. The drop is large. Further, in No. 1, the friction coefficient was too large at around 0.15 even in the initial stage of use, which causes a problem such as a feeling of being caught during a shift operation.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a synchronizer ring according to one embodiment of the present invention, FIG. 2 is a vertical sectional side view of a synchronizer ring according to another embodiment, and FIG.
FIG. 4 is an enlarged view of a main part of the synchronizer ring shown in FIG.
FIG. 5 is a vertical sectional side view of a synchronizer incorporating a synchronizer ring, and FIG. 5 is a graph showing experimental results.
6 (A), (B) and (C) are vertical side views showing the operation of the synchronizer shown in FIG. In the figure, 1 is a synchronizer ring main body, 2 is a pad portion, and 20 is a high pore portion.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-61-149630 (JP, A) Actually open 51-43752 (JP, U) Actually open 61-108536 (JP, U) Actually open 61- 131543 (JP, U)

Claims (4)

[Claims] 1. A synchronizer ring body extending in a circumferential direction having an inner tapered cone portion on an inner peripheral portion thereof, and a pad portion fixed to an inner peripheral surface of the inner tapered cone portion of the synchronizer ring body and made of a friction material as a base material. The pad portion has a high porosity having a higher porosity than other portions of the pad portion, and the area of the high porosity is 10% when the area of the pad portion is 100%. A synchronizer ring characterized by being set to ~ 40%. 2. The high porosity portion of the pad portion has a porosity of 45 to 75%.
And the pad portion other than the high pore portion has a porosity of 20 to
The synchronizer ring according to claim 1, which is 60%. 3. A plurality of high porosity portions are arranged in parallel or substantially in parallel with the axial direction of the synchronizer ring body, or a plurality of high porosity portions are dispersed in a block.
The synchronizer ring described in the item. 4. The pad part comprises a step of forming a primary pad part including a base material made of a friction material and a volatilizing material dispersed in the base material, and the primary pad part is heat treated to produce the volatilizing material. The synchronizer ring according to claim 1, which is manufactured by a step of forming a high pore portion by evaporating.