JPH08170667A - Rotary drum provided with brake band - Google Patents

Abstract

PURPOSE: To efficiently cool a drum main unit by providing a supply oil hole, inserted through the drum main unit, in a rotary drum, and providing a plurality of lubricating oil circulating grooves, extended to escape from the supply oil hole, in an internal peripheral surface thereof. CONSTITUTION: A rotary drum is provided with a drum main unit of double structure providing an outer drum 2 oppositely facing a brake band V and providing an inner drum 1 fixedly held inside this outer drum 2. A single supply oil hole 5 is provided in the outer drum 2 of this drum main unit, also to form a plurality of lubricating oil circulating grooves 10, extended to avoid the supply oil hole, in its internal peripheral surface. In this way, lubricating oil, flowing out from the supply oil hole 4 of the inner drum 1, is allowed to flow in the lubricating oil circulating groove 10, so that a total periphery of the outer drum 2 can be cooled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary drum used for an automatic transmission of a vehicle (a brake drum having a band brake having a wet friction material on its outer periphery and a wet multi-plate clutch inside thereof). With respect to the above, the present invention intends to improve the cooling efficiency of the rotary drum.

[0002]

2. Description of the Related Art As a technique for efficiently lubricating a rotating drum with a simple structure, a disk supporting the drum is provided with a curved portion in the drum direction, and the disk is provided at a radially outer portion of the curved portion. Reference is made to, for example, Japanese Utility Model Laid-Open No. 61-179444 in which a lubricating oil passage is formed in the drum in the thickness direction while a lubricating oil hole is formed in the drum in the thickness direction.

A rotary drum having a double structure composed of an inner drum having a wet multi-plate clutch and an outer drum having the inner drum fixedly held therein is already known, and the rotary drum is a brake. With the band open, the automatic transmission hydraulic fluid (ATF) supplied from the inside of the inner drum is spouted between the drum and the brake band by centrifugal force from the oil supply hole that penetrates both the outer drum and the inner drum. , So that lubrication was performed.

By the way, among the above-mentioned rotary drums, in particular, in the rotary drum having a double structure, since a closed space is inevitably formed between the outer drum and the inner drum, there are the following problems.

That is, as shown in FIGS. 1 (a) and 1 (b), the main part of the rotary drum having a double structure is such that a part of the ATF supplied to the inner drum 1 is of the inner drum 1. The oil is discharged from the opening base end P of the rotary drum along the lubricating oil flow path 3 formed by the spline, and the rest flows into the gap between the inner drum 1 and the outer drum 2 through the oil supply hole 4. 1 (a) and 1 (b), a slight gap is formed between the bulging portion of the inner drum 1 and the outer drum 2 except for a welded portion. A part of the inflowing ATF is jetted to the outer peripheral surface of the drum through the oil supply hole 5 provided in the outer drum 2 and the opening base end P of the drum is formed along the lubrication passage 6 formed by the spline of the inner drum 1. More discharged. Here, in FIG. 1A, the flow of the ATF is delayed on the gap between the inner drum 1 and the outer drum 2 on the right side of the oil supply hole 4, that is, on the closed space K side formed by the inner drum 1 and the outer drum 2. Therefore, cooling of the outer drum by the lubricating oil cannot be expected in that region, and there is a disadvantage that a large amount of lubricating oil is required to suppress the temperature rise due to heat generation when braking by the band brake.

Regarding this point, it is considered that the oil supply holes 4 and 5 are provided at the positions corresponding to the closed space K.
Since the clutch operating piston 7 and its operating chamber 8 are present in the inner drum 1, it is structurally difficult to change the installation position.

In order to improve the cooling efficiency from the outer peripheral surface of the outer drum 2, it is possible to increase the amount of lubricating oil jetted from the supply holes 4, 5 to the outer peripheral surface of the drum. By simply increasing the value of, the brake band V
The lubricating oil supplied between the line nig surface and the outer drum 2 is less likely to be discharged from this gap, so that the friction characteristics of the brake band V are deteriorated (sufficient frictional force cannot be generated), and shocks during shifting are generated. Is inevitable to grow.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to propose a research result in which a drum body can be efficiently cooled (without excessive supply of lubricating oil) by effectively utilizing lubricating oil supplied into the drum. It is in.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a rotary drum having a brake band to which a wet friction material is attached and having a mechanism for applying braking by the brake band.
The brake drum is characterized in that the rotary drum has at least one oil supply hole penetrating the drum body, and has a plurality of lubricating oil flow grooves extending on the inner peripheral surface thereof so as to avoid the oil supply hole. It is a rotating drum equipped with.

Further, according to the present invention, there is provided a rotating drum having a brake band to which a wet friction material is adhered, and braking is performed by the brake band. The rotating drum is an outer drum facing the brake band, and an inner side of the outer drum. A drum body having a double structure including an inner drum fixedly held in the outer drum, the outer drum having at least one oil supply hole, and a plurality of lubricating oil flow grooves extending on the inner peripheral surface of the outer drum to avoid the oil supply hole. Is a rotating drum provided with a brake band.

In the rotary drum having the above construction, it is preferable that the lubricating oil flow groove extends parallel to the rotating direction of the drum main body or extends from the base end of the drum main body to the other base end.

Specifically, the lubricating oil distribution groove extends from the base end of the drum body toward the other base end,
Those that start at the opening base end of the drum body and extend at an angle in the direction of rotation, or those that start at the opening base end of the drum body and extend at an angle in the opposite direction to the direction of rotation, or the opening base of the drum body It is preferable to use a combination of one that extends from the end as a starting point and that extends in the opposite direction to the direction of rotation, and one in which one end of the lubricating oil flow groove communicates with at least one base end of the drum body. desirable.

[0013]

According to the present invention, a plurality of grooves are provided on the inner peripheral surface of the outer drum, and the lubricating oil flowing out from the oil supply hole of the inner drum is made to flow into the grooves to cool the drum. If you adopt such a structure, it is possible to flow the lubricating oil along the circumference of the drum depending on how to extend the groove, and also to flow at a certain angle from the base end of the drum to the other base end, as a result, Since the contact area and contact time of the lubricating oil with respect to the outer drum are increased, the cooling efficiency of the drum is significantly improved.

Particularly, the adverse effect of the existence of the closed space inevitably formed in the rotary drum having the double structure is remarkably reduced.

When the inner drum is narrower than the outer drum, a continuous groove extending from the opening base end of the outer drum to the other base end (closed end) (especially, the groove extending from the opening end in the rotation direction of the drum). By providing the groove, the lubricating oil that tends to flow to the open end along the spline inside the inner drum can be positively poured toward the closed end of the outer drum.

When it is required to positively discharge the lubricating oil flowing into the closed end of the outer drum from the open end, a groove extending from the open end of the drum in the direction opposite to the rotating direction of the drum may be formed. Good.

In the present invention, it is essential to avoid the oil supply hole when forming the groove in order to avoid the deterioration of the friction characteristics of the brake band, but such a condition increases the supply amount of lubricating oil. The same applies to the case where the diameter and number of the oil supply holes of the inner drum are increased in order to do so.

The depth and width of the lubricating oil supply groove, the number of grooves, the distance between the grooves, and the angle of the drum with respect to the rotation axis are:
It is determined by conditions such as the shape of the automatic transmission, the supply amount of lubricating oil, the shape of the groove provided in the lining of the brake band, the size of the heat load, and the surface pressure at the time of fastening the brake band. Since the optimum solution cannot be generally obtained, it is necessary to confirm and set in advance by experiments.

[0019]

FIG. 2 shows a main part (corresponding to the view B of FIG. 1) of the inner surface of the outer drum of the rotary drum according to the present invention (corresponding to the view B in FIG. 1). This is an example in which they extend parallel to each other.

In the case where the outer drum having the structure shown in FIG. 2 is provided, the lubricating oil supplied from the oil supply hole 4 of the inner drum 1 to the inner peripheral surface of the outer drum 2 is rotated by the rotation of the drum. Due to the centrifugal force generated, the drum flows in the direction opposite to the rotating direction of the drum, and the entire circumference of the outer drum is cooled as long as the lubricating oil exists in the groove 10.

FIGS. 3 and 4 show examples in which the lubricating oil flow groove 10 extends from the base end of the outer drum 2 toward the other base end at an angle θ ₁ or an angle θ ₂ .

The groove 10 shown in FIGS. 3 and 4 extends in the direction in which the rotary drum rotates. In this case, the groove 10
Since the lubricating oil in 10 is in a state of flowing substantially along the width direction of the outer drum 2 due to the inertial force generated by the rotation of the drum, not only is it effective in cooling the entire circumference of the outer drum 2, Efficient cooling can be performed also in the width direction. Such a groove 10 on the outer drum 2
When the above is formed, the lubricating oil positively flows toward the opening end P of the drum, so that there is also an advantage that the efficiency of discharging the lubricating oil is increased.

FIG. 5 shows an example in which a groove 10 extending at an angle θ ₃ is formed in the direction opposite to the rotating direction of the rotary drum.

In the structure shown in FIG. 5, when the lubricating hole 4 of the inner drum 1 is arranged in the vicinity of the opening base end P of the drum and a large amount of lubricating oil is supplied thereto, lubrication of that area is performed. Oil is applied to the other base end P ₁ which is the closed end of the drum.
The outer drum 2 can be cooled over its entire width.

In the outer drum having such a structure, the lubricating oil flows from the closed base end P _{1 of} the drum to the open base end P of the drum along the spline of the inner drum 1, but is lubricated again from the oil supply hole 4 of the inner drum 1. Since it also flows into the oil circulation groove 10, the cooling efficiency can be improved.

FIG. 6 shows an example in which a lubricating oil flow groove 10 extending from the opening base end P of the drum body as a starting point and extending in the direction in which the drum rotates and in the opposite direction is provided. The outer drum having such a structure is a drum. Even if the rotor rotates in the reverse direction, the flow of the lubricating oil on the inner peripheral surface is the same, which has the advantage of stabilizing the cooling performance.

FIG. 7 shows the lubricating oil flow groove as shown in FIG.
14 and the ends of these grooves are connected to the opening base end P of the drum body.
The example shown in FIG. In the outer drum 2 having such a configuration, the oil supply hole 4 of the inner drum 1 is irrespective of the rotating direction of the drum (normal rotation or reverse rotation).
Lubricating oil more supplied from the closed proximal end P ₁ of the drum to the open proximal end P, to flow further toward the open proximal end P to the closed proximal end P _1, aim to further improve the cooling performance of the lubricating oil be able to.

[0028]

As described above, according to the present invention,
Since the lubricating oil can be supplied not only to the entire circumference of the outer drum but also to the entire area in the width direction of the outer drum, it is possible to enhance the cooling efficiency of the drum which was difficult in the rotary drum having the double structure, and therefore the brake band. Therefore, it is possible to avoid the convenience of the temperature rise of the drum when the braking is applied (for example, the deterioration of the rotating band and the lining material of the brake band or the clutch parts housed inside the inner liner).

[Brief description of drawings]

1A is a diagram showing a cross section of a rotary drum used in an automatic transmission, and FIG. 1B is a view taken along line AA of FIG. 1A.

FIG. 2 is a diagram showing a configuration of a main part of a rotary drum according to the present invention.

FIG. 3 is a diagram showing a configuration of a main part of a rotary drum according to the present invention.

FIG. 4 is a diagram showing a configuration of a main part of a rotary drum according to the present invention.

FIG. 5 is a diagram showing a configuration of a main part of a rotary drum according to the present invention.

FIG. 6 is a diagram showing a configuration of a main part of a rotary drum according to the present invention.

FIG. 7 is a diagram showing a configuration of a main part of a rotary drum according to the present invention.

[Explanation of symbols]

1 Inner Drum 2 Outer Drum 3 Lubricating Oil Flow Path 4 Oil Supply Hole 5 Oil Supply Hole 6 Lubricating Oil Flow Path 7 Piston 8 Working Chamber 9 Lubricating Oil Flow Groove 10 Lubricating Oil Flow Groove 11 Drive Plate 12 Driven Plate 13 Retaining Plate 14 Snap Ring P Open base end P ₁ Closed base end K Closed space V Brake band

Claims (8)

[Claims] 1. A rotary drum having a brake band to which a wet friction material is adhered, and braking is performed by the brake band, wherein the rotary drum has at least one oil supply hole penetrating the drum body. A rotary drum provided with a brake band, characterized in that it has a plurality of lubricating oil flow grooves extending on the inner peripheral surface thereof so as to avoid the oil supply holes. 2. A rotary drum having a brake band to which a wet friction material is adhered, and braking is performed by the brake band, the rotary drum being fixedly held inside the outer drum and the outer drum facing the brake band. A drum body having a double structure including an inner drum and an outer drum having at least one oil supply hole, and a plurality of lubricating oil flow grooves extending on the inner peripheral surface of the outer drum to avoid the oil supply hole. A rotating drum equipped with a brake band. 3. The rotary drum according to claim 1, wherein the lubricating oil flow groove extends parallel to the rotating direction of the drum body. 4. The rotary drum according to claim 1, wherein the lubricating oil flow groove extends from the base end of the drum body toward the other base end. 5. The rotary drum according to claim 4, wherein the lubricating oil flow groove extends from the opening base end of the drum main body at an angle in the direction of rotation thereof. 6. The rotary drum according to claim 4, wherein the lubricating oil flow groove extends from the opening base end of the drum main body at an angle in a direction opposite to the direction of rotation thereof. 7. The rotary drum according to claim 4, wherein the lubricating oil flow groove is formed by a combination of a base of the opening of the drum body as an origin and a direction of rotation of the base and a direction extending in an opposite direction with an angle. 8. The rotary drum according to claim 4, wherein the lubricating oil flow grooves adjacent to each other communicate with each other at at least one base end of the drum body.