JPS6272947A - Synchronizer ring - Google Patents

Abstract

PURPOSE:To produce such a sliding part that has proper frictional force and being excellent in abrasion resistance at that, by forming a plating film, where hard grains are dispersed, in the sliding part situated in an inner circumference of a synchronizer ring. CONSTITUTION:Plating treatment takes place for a sliding part 50 existing in a contact surface of a top land part 40 of a synchronizer ring 10. This plating takes place in the following process that fine grains of metal or ceramic of bout 1-3mum in average grain size are dispersed in a plating solution whereby a plating film of 5-100mum in thickness is produced. Since hardness of a hard grain is higher than that of a ferrophosohorus plating film and excellent in abrasion resistance, the ferrophosohorus plating film is worn out due to slide motion with a gear cone whereby the hard grain comes forth to the surface so that a high friction factor is stably secured. In addition, surface roughness of the plating film is set to below Rz3mum or so whereby the initial friction factor is reduced and, what is more, any hitch at the time of shifting will not occur at all.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a synchronizer ring for a synchronizer that realizes smooth shifting in a gear transmission.
The friction characteristics and wear resistance of the moving parts have been improved.

The synchronizer ring of the present invention is used, for example, in a full-fh-width transmission.

[Prior Art] In gear transmissions that change gears by meshing gears, if the circumferential speed of the teeth of one gear is not synchronized with the circumferential speed of the other gear, noise will be generated during gear changes, and sometimes damage may occur. Sometimes it invites. A synchronizer is used to synchronize the peripheral speeds of both teeth when meshing gears.

The synchronizer ring forms the main component of the synchronizer and is used for synchronization! It has a sliding part on the inner periphery that generates the vJta force.

By the way, in a VJ car, it is necessary to change gears in a chain type - F1 synchronizer ring) Xisenbu's endurance 1! ? ! Purity is required. Also, l of the sliding part? It is also desirable that the frictional force be within an appropriate range. That is, if the ag friction force is too high, the shift will get stuck during shifting, and if the friction force is low, it will cause poor synchronization. In order to meet the above requirements, attention has heretofore been paid to changing the shape of the sliding part of the synchronizer ring and selecting the material of the sliding part.

[16 problems that the invention attempts to solve] However, the miniaturization of the synchronizer ring has resulted in +1i
Due to the reduction in the sliding area of the l] part and the increase in sliding speed due to higher engine speeds, the m moving parts made of conventional materials (e.g. special high-strength brass) are subject to significant wear.
This led to the premature loss of the necessary frictional performance. Further, in a synchronizer ring having a top land portion in the sliding portion, the contact area of the top land portion quickly expands due to wear, and as a result, the contact surface pressure decreases, making it impossible to obtain sufficient FJ friction force.

The present invention was completed in view of such circumstances,
To provide a synchronizer ring having a sliding part having an appropriate frictional force and excellent wear resistance.

[Technical means for solving the problem] The synchronizer ring according to the present invention has a synchronizer ring that forms a part of a synchronizer for a vehicle transmission. It is characterized by having hard particles dispersed in it to form a tacky film.

The configuration requirements will be explained below.

As mentioned above, the synchronizer ring is the main component of the synchronizer. At the beginning of synchronization, one gear is biased into contact with the other gear, and the friction between the sliding part and the other gear causes the teeth of both gears to tighten. The circumferential velocities of the two are substantially the same. A synchronizer ring is usually a continuous, endless ring, but
Depending on the case, a portion may be cut out. The inner peripheral surface of the synchronizer ring is a sliding surface that slides against the mating material.

The entire inner peripheral surface may be used as a sliding portion, or a portion of the inner peripheral surface may be used as a sliding portion, such as by cutting a circumferential groove to form a top land portion.

Also, the part of the mating material that comes into contact with the staying surface is usually the gear cone part of the gear. When the synchronizer is a Volkwana set, splines are formed on the outer peripheral surface of the synchronizer ring.

The base material of the synchronizer ring can be the same as the conventional material. For example, copper alloys such as bronze and brass, and iron alloys.

As hard particles, various powders, Al2O3, 5tOt
, ZrO2, Ti0z, Th0z, Y20z, Ce0z
oxides such as 5t3N4. Nitride such as D+N, BN, C-BNl, TiC, WCl51c, Cr5Cz, B4C
, ZrC43 carbides, borides such as 7r3z and Cr3ft, and other inorganic fine particles.

The type of hard particles to be used depends on the sliding material, but it is desirable to select particles that have a harder hardness than the material.

Furthermore, the larger the particle size of the hard particles, the better the wear resistance, but if the particle size becomes large, the degree of abrasion of the mating material becomes too high. Therefore, the particle size is selected in consideration of the hardness of the mating material. Generally, about 1 to 3 μm is desirable. If the particle size is smaller than 1 μm, the wear resistance of the sliding part will decrease;
This is because if it exceeds the limit, the mating material will be significantly worn.

The plating film in which the hard particles are dispersed is preferably abrasion resistant, and can be formed by known means. For example, nichrome (N1) plating film, nichrome phosphorus (
N 1-P) plating film, nichrome cobalt phosphorus (
These include Ni-Ce-P) plating film, iron (Fe) plating film, and iron/phosphorus (Fe-P) plating film.

[Embodiment] FIGS. 1 and 2 show an embodiment of the present invention. This embodiment is applied to a synchronization device used in automation. Synchronizer ring 1 in this example
A trapezoidal top land portion 40 is formed on the inner circumferential surface 20 of 0 by a circumferential groove.

Now, top land part 4 of this synchronizer ring 10
The sliding portion 50 existing on the surface around the plate 0 was plated in the following manner.

■Add 150 g of silicon carbide (SIC) particles with an average particle size of 1 μm to the iron/phosphorus electroplating bath.
/R dispersed and coated on the sliding part 50 using this plating bath.
A synchronizer ring was obtained by performing hard particle dispersion plating (hard particle dispersion M in the plating film: 12 wt %) with a film thickness of 0 μm (Example A).

Furthermore, the surface roughness of the plating film was Rz 3 μm or less.

■ Particles of silicon carbide (s + c>) with an average particle size of 1 μm are dispersed at 50 μm/λ in the above iron/phosphorus plating bath, and similarly hard particle dispersion plating ( A synchronizer ring was obtained by dispersing hard particles in the plating film (Example B).

■Silicon carbide (SiC) particles with an average particle size of 3 μm are dispersed in a plating bath at 120A/R and plated in the same manner as above (Example C), or 50Q/R is dispersed in the same manner as above. A synchronizer ring was obtained by plating (Example D).

■Silicon nitride (Si3N4) particles with an average particle size of 1 μm are dispersed at a ratio of 509/1 to an iron/phosphorus plating bath, and the I
W
! A synchronizer ring was obtained by dispersing J z1 and plating in the same manner (Example F).

The sliding parts of the synchronizer ring are all made of special high-strength brass.

(Comparative Example) ■1 A synchronizer ring was obtained in which the driving part 50 was plated with iron and phosphorus that did not disperse hard particles (Comparative Example A)
.

■Electroless nickel phosphorus plating is applied to the W1 moving part 50,
A synchronizer ring was heat-treated at 300° C. for 1 hour (comparative example).

In addition, the sliding part 50 is subjected to electroless iron/phosphorus plating, and
A synchronizer ring was heat-treated at ℃ for 1 hour (Comparative Example c).

Note that these sliding parts are also made of special high-strength brass.

■A synchronizer ring with a sliding part made of special high-strength brass (conventional material) whose composition is 62Cu-0.98
i-0,I Fe-3,1A l-Remaining Zn (comparative example), its composition is 61Cu-2,6Fe-
1,9+-5,4AI-Remaining Zn was designated as (Comparative Example E).

The synchronizer rings of Examples and Comparative Examples obtained above were assembled into actual machines and operated 50,000 times (speed change operations were performed), and a wear test and an operation durability test were conducted. The unity is shown in the table.

The operation will be explained below. First, by moving the gear shift lever, the sleeve 2 moves in the direction of the arrow x as shown in FIG. 3 (△), and the synchronizer key 3 moves together. Then, synchronizer key 3
The synchronizer contacts the ring 10 and presses it.
The first rib part 50 of the ring 1o is the gear cone part 5 of the gear 4.
gear 4 due to the friction generated at that time.
It starts spinning. Further, as the sleeve 2 moves in the direction of the arrow X as shown in FIG. hits the tip of the spline 90 of the synchronizer ring 10, and at this point the movement of the sleeve 2 is blocked by the sink [■ teaser ring 10]. Therefore, the sleeve 2 strongly presses the synchronizer ring 10. Therefore, the IFJ 1, 11 portion 50 of the synchronizer ring 10 is pressed against the gear cone portion 5, generating a large frictional force, so that the rotation of the sleeve 2 and the rotation of the gear 4 become the same circumferential speed. When the synchronization is completed in this way and the relative speed difference between sleeve 2 and gear 4 is eliminated, when sleeve 2 is further moved in the direction of arrow The spline of gear 4 meshes with the spline of gear 4, and the shift is completed.

(Evaluation) The table clearly shows that the synchronizer ring according to the example has a lower wear depth after the wear test than the comparative example, and has excellent wear resistance.

Furthermore, it can be seen that the If friction coefficient after the vJ durability test is also higher than that of the comparative example.

Furthermore, FIG. 4 shows the change in the friction coefficient during the operation durability test on the day of the example and on the comparison side port. From FIG. 4, it is clearly seen that Example IIj has a stable coefficient of friction.

(Effects of Actual 1M Example) In this example, the hardness of the VP quality powder particles is higher than that of the iron/phosphorus plating film, and the wear resistance is excellent, so the IF with the gear cone! The ribs first wear away the iron/phosphorus plating film that is the matrix, and as shown in FIG. 5, hard particles come out to the surface of the active part, causing friction between the hard particles and the gear cone.

Therefore, high contact surface pressure can be obtained. Also, @F! It has higher hardness than the counterpart material (A-yacorn) and slightly roughens the surface of the gear cone. Therefore, it is possible to prevent the *m coefficient from decreasing after the break-in, and a high sty coefficient can be stably obtained.

From this, it is possible to obtain a synchronizer ring that has high wear resistance and maintains stable frictional force even after breaking in.

In addition, in this example, the particle size of the hard particles was set to 1 μm to 3 μm.
By setting m, the degree of wear between the sliding part and the mating gear cone was kept within an appropriate range.

This is because when the hard particles have a diameter smaller than 1 .mu.m, the wear resistance of the sliding part decreases, and on the other hand, when the particle diameter exceeds 3 .mu.m, the gear cone is significantly worn down.

In addition, by setting the surface roughness of the plating film to R23μm or less, the initial coefficient of friction until it becomes familiar is reduced,
Prevented from getting stuck when shifting.

[Effects] As described above, the present invention provides wear resistance and long-term stable friction force by applying hard particle dispersion plating to the sliding parts of the synchronizer.

[Brief explanation of drawings]

FIG. 1 is a longitudinal side view of the synchronizer ring. FIG. 2 is a partially vertical side view of the synchronizer ring. Figures 3, (A), (B), and (C) are partial longitudinal cross-sections of the synchronization position for explaining the operation of the synchronizer ring.
It is a front view. FIG. 4 shows the change in the friction coefficient of the sliding article during the operational durability test. Figure 5 shows ll! ! FIG. 2 is a schematic longitudinal cross-sectional side view of the hard particle dispersed plating film of the l#J portion. 10... Synchronizer ring 20... Inner peripheral surface 40... Top land portion 50... Sliding product

Claims (4)

[Claims] (1) A synchronizer ring constituting a part of a synchronizer for a vehicle transmission, characterized in that a plating film in which hard particles are dispersed is formed on the sliding part on the inner circumference of the synchronizer ring. ring. (2) The synchronizer ring according to claim 1, wherein the hard particles are metal or ceramic fine particles having an average particle size of about 1 to 3 μm. (3) The plating film in which the hard particles are dispersed includes a nichrome (Ni) film, a nichrome phosphorus (Ni-P) film, a nichrome cobalt phosphorus (Ni-Co-P) film, and an iron (
The synchronizer ring according to claim 1, which is one of a Fe) film and an iron-phosphorous (Fe-P) film. (4) The hard fine particle-dispersing film has a thickness of 5 to
Synchronizer ring according to claim 1, having a thickness of 100 μm.