JPH0763247A - Torque converter - Google Patents

Abstract

PURPOSE:To provide a torque converter having judder hardly generated in the initial stage during slip control. CONSTITUTION:In the lockup clutch of a torque converter provided with a frictional plate having a ring-like frictional member, a partner plate 2 to be relatively rotated to the frictional plate, and having a surface to be worn 20 to be brought in slidable-contact with the frictional member and oil interposed betwthe the frictional member and the surface to be worn 20, the surface to be worn 20 is formed by an irregular surface having the pitch distance of 0.3+ or -0.5mm in the radial direction, and the sum SIGMAl (l+l+l+...) of lengths l of top surfaces 22 of projecting parts 21 of the irregular surface is set to 50% (tp) or less of the width L of the surface to be worn 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque converter installed and used in a transmission system for transmitting a driving force of an automobile engine to wheels.

[0002]

2. Description of the Related Art As a conventional torque converter (hereinafter referred to as a torque converter), for example, in order to improve fuel economy when a vehicle speed exceeds a predetermined value, a friction plate having a ring-shaped friction material and a friction plate are used. What is provided with a so-called lock-up mechanism, which is composed of a mating plate having a surface to be frictionally rotated relative to the plate and in sliding contact with the friction material, is used.

According to this torque converter, when the vehicle speed exceeds a predetermined value, the friction plate is pressed against the surface to be rubbed of the mating plate to be directly connected thereto, and the driving force is mechanically transmitted to the torque converter during fluid driving. The effect of eliminating torque loss and improving fuel efficiency can be obtained. In a torque converter equipped with a lockup mechanism, the vehicle speed is lower to improve fuel economy,
In a region where mechanical fluctuations are large, control for transmitting torque while slipping slightly, that is, slip control is being studied.

[0004]

However, when the slip control is performed, the judder may be generated between the friction plate and the mating plate in the initial stage where the conformity between the friction plate and the mating plate is not sufficient. . An object of the present invention is to provide a torque converter in which judder is less likely to occur in the initial stage during slip control.

[0005]

DISCLOSURE OF THE INVENTION The present invention is directed to a friction plate having a ring-shaped friction member, a mating plate having a surface to be rubbed which is rotated relative to the friction plate and is in sliding contact with the friction member, and the friction member. In the torque converter having the oil interposed between the friction surface and the friction surface, the friction surface is formed with a concavo-convex surface with a pitch interval of 0.3 ± 0.1 mm in the radial direction. The sum of the lengths of the top surfaces of the convex portions is 50% or less of the width of the abraded surface.

The pitch (mm) interval of the uneven surface is 0.3.
The reason for setting the range to ± 0.1 mm is that if the pitch is in this range, an appropriate amount of oil is supplied between the friction surface of the mating plate and the friction material that is in sliding contact, and an appropriate oil film is formed in the contact area. It Therefore, the friction surface and the friction material, the familiarity between the friction surface and the friction material progresses from the early stage of use,
It is possible to reduce the occurrence of judder. In particular, it is more preferable that the pitch (mm) interval of the uneven surface is within a range of 0.3 ± 0.05 mm.

If the pitch is less than 0.20 mm, sufficient oil cannot be stored and judder is likely to occur. If the pitch exceeds 0.40 mm, the oil film formed between the surface to be rubbed and the friction material becomes excessive, the progress of the familiarization is delayed, and judder is likely to occur. In addition, since the sum of the lengths of the top surfaces of the convex portions is 50% or less of the width of the friction surface, the friction surface and the friction material have a relatively high contact surface pressure during sliding contact, and are not familiar with each other. It is possible to proceed and reduce the occurrence of judder. The preferable ratio of the sum of the lengths of the tops of the protrusions of the uneven surface to the width of the surface to be rubbed is 30% or less. Here, the top surface means a plateau surface formed by vanishing or the like after turning.

[0008]

According to the torque converter of the present invention, since the friction surface of the mating plate is formed by the uneven surface having a pitch interval of 0.3 ± 0.1 mm in the radial direction, friction with the friction surface of the mating plate occurs. At the time of sliding contact with the material, an appropriate amount of oil is supplied between the surface to be rubbed and the friction material, and an oil film is formed in the contact area.

Further, the friction surface and the friction material become more familiar with the friction surface and the friction material from the early stage of use, so that the occurrence of judder can be reduced. Moreover, since the sum of the lengths of the top surfaces of the convex portions of the uneven surface is 50% or less of the width of the friction surface, the contact surface pressure between the friction surface and the friction material is relatively high during sliding contact, Familiarity progresses quickly and the occurrence of judder can be reduced.

Further, by these, the shock can be reduced when the lock-up mechanism is operated to switch between lock and lock.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a torque converter (hereinafter referred to as a torque converter) of the present invention will be described with reference to FIGS. As shown in FIG. 1, the torque converter 1 of the embodiment has a mating plate 2, a friction plate 3, a turbine 4, and a stator 5 which are rotatable and which are sequentially arranged along an axis O.
And an impeller 6 and oil 7, and is installed and used in a transmission system that transmits the driving force of an automobile engine to wheels.

The mating plate 2 is made of metal and is shown in FIG.
2 which shows a plan view seen from the arrow A in FIG. 3 and FIG. 3 which is enlarged in the cross-sectional arrow A1-A1 in FIG. 2 and has a friction surface 20 which is in sliding contact with the friction material 31 of the friction plate 3. . The friction surface of the mating plate 2 has a pitch interval P of 0.25, 0.30, 0.3 in the radial direction.
Three types (see Table 1) formed on a 5 mm uneven surface were manufactured. The depth of the uneven surface was 12, 20, and 26 μm. Subsequently, a top surface 22 was obtained on the convex portion 21 of the concave and convex surface as a plateau surface having the apex flattened by vanishing (the depth of the concave and convex surface at this time was 6, 9 and 12 μm). Each of these three types of mating plates 2 has a top surface 2 of a convex portion 21 having an uneven surface with respect to the width L of the friction surface 20.
The percentage of the sum Σl (l + 1 + l + ...) Of the length l of 2 (hereinafter referred to as tp) is set to 30%. Top surface 22 here
The length l of was measured by a cut surface cut by a surface having a depth of 1 μm from the top surface 22 of the convex portion 21.

To form the friction surface 20 of each mating plate 2 as an uneven surface having a pitch interval P of 0.25, 0.30 and 0.35 mm, cutting was performed using a lathe. Each of the mating plates 2 is used by being connected to a crank shaft 24 of an engine (not shown). The friction plate 3 includes a metal ring-shaped base material 30 and a paper ring-shaped friction material 31 that is joined to the surface of the ring-shaped base material 30 to form a friction surface 32. The friction plate 3 is connected to an input shaft 34 of a transmission (not shown).

The turbine 4, the stator 5 and the impeller 6 are arranged at positions facing each other with a predetermined space therebetween. The turbine 4 is connected to the input shaft 34. The stator 5 is mounted on a stator shaft 51 arranged concentrically on the outer peripheral side of the input shaft 34 via a one-way clutch 50. The impeller 6 is connected to the crank shaft 24.

As the oil 7, an automatic transmission hoodle (ATF) is used. In the case of using the torque converter 1 of the embodiment configured as described above, the pitch P intervals of the uneven surface formed on the friction surface 20 of each mating plate 2 are 0.25, 0.30, 0.3.
Since 5 mm and tp are set to 30%, a sufficient amount of oil can be retained in the concave portion 22 of the uneven surface, and the friction surface 20 has an appropriate amount between the friction surface 31 and the friction surface 31 of the friction plate 3 in sliding contact. Oil 7 is supplied, and an oil film is formed substantially uniformly in the contact area in the sliding direction. Therefore, the mating plate 2 and the friction plate 3 become more familiar with the friction surface 20 and the friction surface 31 from the early stage of the number of times of use, and dμ (fine change in friction coefficient) / dv (fine change in speed). Is positive, and the occurrence of judder can be reduced.

(Comparative Example) Next, in order to confirm the effect of the torque converter 1 of the example, the pitch P interval of the uneven surface and tp
A test sample of a comparative example set to 8 types shown in Table 1 was prepared, and the test results using the three types of mating plates 2 of the above-described example were shown in FIG.

In the test sample of the comparative example, the pitch P intervals of the uneven surface are 0.10, 0.20, 0.40, 0.
4 types with 50% tp and 30% tp each, and the same pitch P intervals of 0.25, 0.30 and 0.35 mm with 60% tp each
The same pitch P interval is 0.30 mm and tp is 8
A total of 8 types were created, including 1 type of 0%. In addition, each test sample of the comparative example is formed by turning the friction surface of the mating plate with a lathe at a predetermined pitch and then performing a varnish finish and adjusting the plateau rate to various plateau rates depending on the strength of the varnish. Equipped plateau surface.

[0018]

[Table 1] (Conditions for Comparative Test) The μ-V characteristic was evaluated by combining with a cylinder having a friction material adhered thereto by means of a thrust / color type friction tester (not shown).

The friction area when the two are in sliding contact is 2 cm ²
Is. Then, soak in 100 ° C ATF, load 40kgf, and slide speed from 2m / s to 0.01m.
Μ was measured when the value was reduced to / s. Then, based on this measurement, dμ / dv was calculated in the section where the sliding speed was 2 m / s to 1 m / s. (Evaluation) As a result of the test, as shown in FIGS. 4 and 5, the test sample of the comparative example has a pitch of 0.
In the case of 20 mm or less and in the case of 0.40 mm or more, it was found that even if tp was 30%, dμ / dv became negative, which was a disadvantageous characteristic for the occurrence of judder. Furthermore, the test sample of the comparative example has a pitch of 0.25 mm,
0.30 mm, 0.35 mm (so-called 0.3 ±
Even within 0.05 mm), tp is 60% or 8
It was found that when it is 0%, dμ / dv becomes close to 0 or becomes negative, which is a disadvantageous characteristic for the occurrence of judder.

In the test sample of the embodiment, the pitch P intervals of the uneven surface are 0.25, 0.30 and 0.35 mm.
Since tp is set to 30%, as shown in FIG. 4, as compared with the case of the test sample of the comparative example, dμ / dv becomes positive even if the variation is included, and the countermeasure against judder is more preferable. It turned out to be In addition,
The tp of the above embodiment is not limited to 30%, and the pitch P interval is 0.3 ± 0.05 as seen in FIG.
If it is mm, tp is 50% or less, which is effective as a countermeasure against judder.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an entire torque converter in an embodiment.

FIG. 2 is a plan view showing a mating plate forming the torque converter in FIG. 1 as viewed in the direction of arrow A.

FIG. 3 is an enlarged view of the friction plate in FIG. 2 taken along the line A1-A1 of FIG.

FIG. 4 shows a plateau rate (tp) on the horizontal axis and dμ on the vertical axis.
It is a figure which shows the ratio of (a minute change of a friction coefficient) and dv (a minute change of speed).

FIG. 5 shows the pitch (mm) of the uneven surface on the horizontal axis, and dμ (fine change of friction coefficient) and dv (fine change of speed) on the vertical axis.
It is a figure which shows the ratio with.

[Explanation of symbols]

1 ... Torque converter 2 ... Counter plate 20 ... Friction surface 21
... Convex portion 22 ... Top surface 23 ... Concave portion 3 ... Friction plate 30 ... Ring-shaped friction material 31
… Friction surface 4… Turbine 5… Stator 6
... Impeller 7 ... Oil tp ... Percentage of the sum of the length of the top surface of the convex portion of the uneven surface with respect to the width of the friction surface

Claims (1)

[Claims] 1. A friction plate having a ring-shaped friction member,
In a torque converter having a mating plate that has a surface to be rubbed that rotates relative to the friction plate and is in sliding contact with the friction material, and an oil that is interposed between the friction material and the surface to be rubbed, the surface to be rubbed is The pitch interval in the radial direction is 0.3 ± 0.1
The torque converter is characterized in that the sum of the lengths of the top surfaces of the projections of the uneven surface is 50% or less of the width of the surface to be rubbed.