JP3512102B2 - Synchronizer ring - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synchronizer ring. The synchronizer ring can be used for a transmission such as a vehicle. 2. Description of the Related Art As a synchronizer ring, as shown in FIG. 5, a base material 100 extending along a ring shape is used.
And a friction material layer 120 which is coated on the inner peripheral surface of the base material 100 and rubs against the mating cone 201 of the mating material 200 (Japanese Utility Model Laid-Open No. 63-36745).
JP-A-3-287705). [0005] As shown in FIG. 5, the base material 100 moves from the side A1 where the mating cone 201 is inserted toward the side B1 farther from the side A1 where the mating cone 201 is inserted.
The inner peripheral surface 100a is a conical surface inclined in a direction of gradually decreasing the diameter. When a synchronizing action is obtained by the synchronizer ring, the conical mating cone 201 of the mating material 200 moves relative to the friction material layer 120 of the synchronizer ring, and the two slide frictionally. At this time, the friction material layer 120 and the mating cone 201 frictionally slide from the side B1 far from the side A1 into which the mating cone 201 is inserted. [0004] In such a synchronizer ring, a mating cone 201 is formed on the friction material layer 120.
Tend to be large. In some cases, the synchronizer ring and the opponent material 200 are too close to each other, and depending on the use conditions, there is a possibility that the two may come into contact with each other. [0005] Therefore, in the conventional synchronizer ring, it is necessary to set the shoulder clearance SC, which is the initial distance between the synchronizer ring and the counterpart material 200, to be large. As described above, when the shoulder clearance SC is increased, there is a limit in shortening the shift stroke and a shift time, and there is a limit in improving the shift feeling. The present invention has been made in view of the above circumstances, and has as its object to provide a synchronizer ring which is advantageous for further improving the shift feeling. The present inventor has developed a synchronizer ring. As a result, if the density of a portion of the friction material layer near the side where the mating cone is inserted is set to be high, the friction can be reduced. This is advantageous in that it is possible to reduce unnecessary bite in the friction material layer while securing the necessary bite in the material layer, thereby shortening the shoulder clearance, shortening the shift stroke, and shortening the shift time. It was found that the shift feeling can be improved, and the present invention was completed based on this finding. That is, the synchronizer ring of the present invention is formed by a base material extending along the ring shape, and a conical inner circumferential surface coated on the inner circumferential surface of the base material and rubbing with a mating cone.
And a friction material layer having a friction surface formed.In the friction material layer, a portion closer to the side where the mating cone is inserted is thicker than a portion farther from the side where the mating cone is inserted.
Thin and density are high rather set, the inner circumferential surface of the substrate,
It is characterized by being substantially parallel to the axis of the substrate . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A base material constitutes a main part of a synchronizer ring, and extends along a ring shape. The material of the substrate can be generally formed of an iron-based sintered metal. The friction material layer is coated on the peripheral surface of the base material and rubs against the mating cone during the synchronous operation. The friction material layer is generally coated on the inner peripheral surface of the base material. The material of the friction material layer can be formed of a sintered metal mainly composed of a metal having good friction characteristics, such as a copper-based metal, a nickel-based metal, and a copper-nickel-based metal. The boundary between the friction material layer and the base material is preferably metallurgically bonded in order to enhance the peel resistance between the two. At the time of metallurgical joining, a liquid phase is generated at the boundary between the friction material layer and the base material, and the two can be strongly joined by utilizing solidification of the liquid phase. The thickness of the friction material layer can be appropriately selected, and the minimum thickness of the friction material layer is, for example, 0.2 to 0.4 mm.
The thickness of the maximum thickness portion of the friction material layer can be, for example, about 1.0 to 2.0 mm. However, it is not limited to this value. According to the synchronizer ring of the present invention, in the friction material layer, a portion closer to the side where the counterpart cone is inserted has a higher density than a portion farther from the side where the counterpart cone is inserted. If expressed in relative terms, the density ratio can be expressed as: density of the part on the side where the counterpart cone is inserted: density of the part farther than the side where the counterpart cone is inserted = 100: (70 to 90). However, it is not limited to this ratio. As exemplified in the embodiments described later, in the cross section of the synchronizer ring, the inner peripheral surface of the substrate can be set substantially parallel to the axis of the substrate. Embodiments of the present invention will be described below with reference to the drawings. The synchronizer ring 1 of the present embodiment has a sintered two-layer structure, and has a base material 10 extending along the ring shape and a friction coating along the inner peripheral surface 10a of the base material 10. And a material layer 12. The substrate 10 is made of a sintered alloy obtained by sintering an iron (Fe—Cu—C) compact. The inner peripheral surface 10a of the base material 10 extends along the axis P1 of the base material 10 and is set substantially parallel to the axis P1. The teeth 1 are provided on the outer peripheral portion of the base material 10 at predetermined intervals along the circumferential direction thereof.
0b are provided in a number of rows, and the notch grooves 10c
Is formed. The target inner diameter DE of the inner peripheral surface 10a of the base material 10 is set to 67.4 mm. The target outer diameter DF of the outer peripheral surface 10h excluding the tooth portion 10b of the base material 10 is 79.
It is set to 8 mm. In FIG. 1, the side on which the mating cone is inserted is indicated as A, and the side A on which the mating cone is inserted is shown as A.
The side farther from is shown as B. Friction material layer 12
Is made of a sintered alloy obtained by sintering a compact of copper-nickel-based metal. The boundary between the friction material layer 12 and the base material 10 is metallurgically bonded by a sintering process. The substrate 10
Is higher in Young's modulus and higher in rigidity than the material forming the friction material layer 12. As shown in FIG. 1, a friction surface 12a, which is an inner peripheral surface of the friction material layer 12, has a conical shape. That is,
The friction surface 12a of the friction material layer 12 is inclined linearly so as to gradually decrease in diameter from the side A into which the counterpart cone is inserted to the side B farther away. The target inclination angle θ of the friction surface 12a with respect to the parallel line P2 of the axis P1 of the base material 10 is 7 degrees. The outer peripheral surface 12b of the friction material layer 12 which is a boundary with the base material 10 is set substantially parallel to the axis P1 of the base material 10. According to the present embodiment, as can be understood from FIG. 1, the side A of the friction material layer 12 where the mating cone is inserted is the minimum thickness portion of the friction material layer 12. The thickness t1 of the minimum thickness portion is about 0.2 mm. The side A of the friction material layer 12 into which the mating cone is inserted
The farther side B is the thickness of the maximum thickness portion of the friction material layer 12. The thickness t2 of this maximum thickness portion is 1.0
mm. Therefore, the friction material layer 12 is thin as a whole. According to the present embodiment, the portion of the friction material layer 12 on the side A on which the mating cone is inserted has a high density. That is, the portion near the side A is the high-density region 12.
x. The high-density area 12x has a higher density than the density on the far side B. According to the relative display, the density ratio is the density of the high-density region 12x: the density of the far side B = 10.
0: 70 to 90. Specifically, when the present inventor measured,
The density of the portion on the far side B in the friction material layer 12 is 4.7 to
The density was 5.0 gf / cm ³ , and the density of the high-density region 12x was 5.7 to 6.0 gf / cm ³ . It should be noted that the density ratio and the density value are merely examples, and are not limited to these values and ranges. The measurement of density is
The structure of the friction material layer 12 was observed with a microscope, and was determined based on the area ratio of the metal matrix constituting the structure, while taking into account the porosity and the amount of graphite in the structure. FIG. 3 schematically shows a compacting process as a manufacturing process. The compacting step will be described with reference to FIG. First, as shown in FIG.
A die 20 having a die 20, a movable core 21 fitted in a die hole 20a, a movable ring-shaped lower punch 22, and a movable ring-shaped lower punch 23 is prepared. Before powder filling, the height of the upper surface 23a of the lower punch 23 substantially corresponds to the height of the upper surface 21a of the core 21.
As shown in FIG. 3A, the base material powder K constituting the base material 10 is filled in the ring-shaped cavity 25. Next, FIG.
As shown in (B), the upper part of the cavity 25 filled with the base material powder K is pressed by the pressure receiving plate 26. In that state,
The lower punch 22 is raised by ΔL in the arrow Y1 direction, and the base powder K in the cavity 25 is pre-compressed in the axial direction. Thereby, the base powder K becomes a green compact. Next, as shown in FIG. 3C, the core 21 and the lower punch 23 are lowered in the direction of the arrow Y2 to form the sub-cavity 27 inside the base powder K. Next, FIG.
As shown in (D), the friction material layer 12 is
Is filled with the friction material powder M. Next, as shown in FIG. 3E, the core 21 is raised in the direction of the arrow Y1 while maintaining the height of the lower punch 23. Thus, the excess friction material powder M in the sub cavity 27 is discharged. At this time, as shown in FIG. 3 (E), the portion in which the friction material powder M is loaded has a thin ring shape with a small thickness tc (about 1 mm), and the inner peripheral surface and the outer peripheral surface are (= Shaft core P mentioned above
It is along 1). Next, as shown in FIG.
8 is lowered in the direction of the arrow Y2 and pressed into the base material powder K and the friction material powder M, and the base material powder K and the friction material powder M are compressed in the axial direction to obtain a ring-shaped green compact R. At this time, the core 21 is also lowered in the direction of the arrow Y2 in conjunction with it. As described above, at the stage before the upper punch 28 is pressed, the base material powder K has already been pre-compressed, but the friction material powder M has not been compressed. Therefore, the friction material powder M is effectively compressed by the upper punch 28. FIG. 3G schematically shows an enlarged main part of FIG. 3F. As shown in FIG. 3G, the upper punch 28
Is a tapered conical surface 28a having a diameter gradually decreasing toward the lower end, and a ring surface 2 extending in the horizontal direction.
8b. The outer diameter DB of the large diameter portion 28f of the conical tapered surface 28a is larger than the outer diameter DA of the small diameter portion 28e of the conical tapered surface 28a. Therefore, when compressing the friction material powder M, the small diameter portion 28 of the conical tapered surface 28a of the upper punch 28
e, the degree of compression in the radial direction is small.
The degree of compression in the radial direction by the large-diameter portion 28f of the conical tapered surface 28a of FIG. 8 is large. Accordingly, as described above, the high-density region 12x is formed by the large-diameter portion 28f of the conical tapered surface 28.
The friction material layer 12 is formed on the side A into which the mating cone is inserted. After the compression, the green compact R is placed in a molding machine 24.
Then, it is heated and held at a sintering temperature (1100 to 1250 ° C.) for a predetermined time (30 to 60 minutes) to perform a sintering process, so that the base material powder K and the friction material powder M are integrated. In addition,
The inner peripheral surface of the friction material layer 12 composed of the friction material powder M is generally used without machining. When the synchronizer ring 1 is used, as can be understood from FIG. 2, the synchronizer ring 1 relatively moves along the axial direction and approaches the counterpart material 4. The mating member 4 has a ring shape made of metal (alloy steel), and has a tooth portion 4a formed on the outer peripheral portion and a mating cone 4c having a conical surface shape whose diameter decreases toward the tip. When the synchronizer ring 1 relatively approaches the counterpart cone 4c, the friction surface 12a of the friction material layer 12 of the synchronizer ring 1 and the counterpart cone 4c of the counterpart material 4 frictionally slide. This provides a synchronizing effect. At the time of synchronization, the synchronizer ring 1
From the smaller diameter side of the friction material layer 12, that is, the far side B, comes into contact with the mating cone 4c. External force applied to the synchronizer ring 1 is basically given from the tooth portion 10b,
Ultimately, the entire surface of the friction surface 12a of the friction material layer 12 of the synchronizer ring 1 is designed to hit the opposing cone 4c. As described above, in this embodiment, the portion of the friction material layer 12 close to the side A on which the mating cone 4 is inserted is located on the side B farthest from the side A on which the mating cone 4c is inserted.
Density is higher than. That is, the high-density region 12x
Is provided. Therefore, the distant side B of the friction material layer 12 and the mating cone 4c can be slidably satisfactorily, and the necessary bite necessary for the synchronization action can be secured. Friction material layer 1
The far side B of 2 has a relatively lower density than the high-density region 12x. When the density is relatively low, compared to when the density is relatively high, it is easier to secure the ground contact area earlier, the rise characteristics of the friction coefficient μ from the start of friction are good, and the friction sliding The property that it is easy to secure the necessary frictional sliding at the initial stage is obtained. When the movement of the synchronizer ring 1 proceeds further, the high-density region 12x of the friction material layer 12 of the synchronizer ring 1 presses the mating cone 4c, so that excessive biting is suppressed. This is because the high-density region 12x has a higher Young's modulus and a higher rigidity than the case where the density is low. Therefore, according to the present embodiment,
The synchronizer ring 1 and the opponent member 4 being too close to each other more than necessary is effectively suppressed by the high-density region 12x. In order to suppress such close approach, the shoulder clearance SC, which is the initial distance between the mate member 4 having the mate cone 4c and the synchronizer ring 1, can be set small. If the shoulder clearance SC can be set small in this way, the shift stroke and the shift time can be shortened by that much, and the shift feeling can be improved. As a relative display, when the size of the shoulder clearance SC of the synchronizer ring according to the prior art having the same size is set to 100, the shoulder clearance SC of the synchronizer ring 1 according to the present embodiment is: It can be reduced to about 60 to 70, which is shorter than the prior art. In the synchronizer ring 1 which receives a load in the diameter increasing direction by the mating cone 4c,
What greatly affects the strength is the thickness of the base material 10. If the thickness of the base material 10 is increased while securing the diameter of the friction surface 12a, the outer diameter of the synchronizer ring 1 tends to increase. In this respect, according to the present embodiment, as can be understood from FIG. 1, the thickness of the side A of the friction material layer 12 is thin, and the inner peripheral surface 10a of the base material 10 is substantially aligned with the axis P1 thereof. Running parallel. Therefore, it is advantageous to increase the thickness of the base material 10 while securing the size of the diameter of the friction surface 12a of the friction material layer 12. Therefore, it is advantageous for increasing the strength of the synchronizer ring 1 in the radially expanding direction and improving the durability. (Application Example) FIG. 4 shows an application example applied to a transmission of a vehicle. In this example, an input gear 51 is formed on the input shaft 50. An end of an output shaft 53 is rotatably fitted in a shaft hole 50 c of the input shaft 50 via a bearing 52. On the output shaft 53, a mating member 54, which is a speed change gear having dog teeth 54 a and a mating cone 54 c, is held via a bearing 55. A clutch hub 58 is fitted to the output shaft 53 with a spline 57. A clutch sleeve 60 is engaged with the clutch hub 58 with a spline 61. The clutch hub 58 has a plurality of grooves 58a.
Is formed, and the synchronizer ring key 6 is inserted into the groove 58a.
4 is movably held. Clutch sleeve 60
The shift fork is engaged with the outer groove 60c. A set of synchronizer rings 1 inside the clutch sleeve 60
Is arranged. (Supplementary Note) The following technical ideas can be understood from the above description.・ Consists of a base material extending along the ring shape and a friction material layer coated on the inner peripheral surface of the base material and rubbing with the mating cone,
The inner circumferential surface of the base material is substantially parallel to the axis of the base material, and the inner circumferential surface of the friction material surface has a large diameter on the side where the mating cone is inserted, and the side where the mating cone is inserted. A synchronizer ring characterized by a small diameter conical surface on the side farther from. This is advantageous for securing the thickness and strength of the base.・ It has a base material powder loaded in a ring shape and a friction material powder loaded in a ring shape on the inner peripheral surface of the base material layer, and a boundary between the base material layer and the friction material powder layer is formed. A ring-shaped molded body that is substantially parallel to the axis and the inner peripheral surface of the layer of the friction material powder is substantially parallel to the axis, and the diameter is reduced toward the tip by being pushed into the molded body And a punch having a conical tapered surface inclined in a direction, and pressing the punch into the inside of the ring-shaped molded body, thereby increasing the density of the friction material powder layer on the side where the mating cone is inserted. 2. The method for producing a synchronizer ring according to claim 1, wherein a green body is obtained and the green compact is sintered. According to the synchronizer ring of the present invention, in the friction material layer, the portion closer to the side where the mating cone is inserted is more than the side farther to the side where the mating cone is inserted. The density has been increased. In other words, the portion of the friction material layer near the side where the mating cone is inserted has a relatively high density and a relatively high Young's modulus. On the other hand, the portion farther from the side where the counterpart cone is inserted has a relatively low density and a relatively low Young's modulus. Therefore, according to the synchronizer ring of the present invention, it is advantageous to suppress unnecessary biting while securing biting necessary for obtaining sliding characteristics. According to the present invention, a portion having a high density, that is, a portion close to a side where the counterpart cone is inserted can suppress excessive biting of the counterpart cone. Therefore, it is advantageous to minimize the shoulder clearance, which is the initial distance between the synchronizer ring and the counterpart material having the counterpart cone. Therefore, it is advantageous in shortening the shift stroke and the shift time, and the shift feeling can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a main part of a synchronizer ring according to the present embodiment. FIG. 2 is a sectional view of a main part of the synchronizer ring according to the embodiment in a state of use. FIG. 3 is a process diagram schematically showing a molding process. FIG. 4 is a cross-sectional view of a vehicle synchronizer showing an application example. FIG. 5 is a sectional view of a main part of a synchronizer ring according to the related art. [Description of References] In the drawings, 1 is a synchronizer ring, 10 is a base material, 12
Denotes a friction material layer, 12a denotes a friction surface, and 12x denotes a high density region.

Claims (1)

(57) [Claim 1] A base material extending along a ring shape, and a conical surface coated on the inner peripheral surface of the base material and rubbing against a mating cone.
And a friction material layer having a friction surface formed by an inner peripheral surface of the friction material layer. In the friction material layer, a portion near the side where the mating cone is inserted is a portion far from the side where the mating cone is inserted. Thicker than
Are the thin and density rather high setting, the inner peripheral surface of the substrate is approximately with the axis of the base material
Synchronizer ring characterized by being parallel .