JPS6084471A - Friction element lubricating structure for automatic speed change gear - Google Patents

Abstract

PURPOSE:To facilitate working by forming a lubricating window onto a transmission case. CONSTITUTION:A lubricating window 29 is formed onto a transmission case 1 right above a brake back 23. Therefore, the oil which leaks from a control valve 26 always flows-down onto the brake back 23. Since the oil which flows-down from the lubricating window 29 lubricates a variety of friction elements, certain lubrication is permitted without forming a complicated lubricating passage.

Description

Detailed Description of the Invention Technical Field The present invention provides a friction element lubrication structure for an automatic transmission, particularly a □friction element lubrication structure suitable for lubrication of a friction element of an automatic transmission that can flow down leakage oil from a control pulp. It is related to.

Conventional automatic transmissions generally perform automatic gear changes by selectively operating various friction elements such as clutches and brakes to switch power transmission paths.

In order to shorten the axial dimension, especially when used in a narrow engine room such as a front engine or front drive vehicle, each clutch is placed radially inward of the transmission case, and the clutches are placed around the clutches. It is common to place brakes on the outer periphery of the vehicle. (For example, Japanese Patent Application Laid-Open No. 55-40865.) These friction elements are often selectively activated depending on the driving conditions, and lubrication for the movement of the friction elements is a very important issue. For this reason, in the past, in order to reliably send oil to the various friction elements arranged inside the transformer case, it was necessary to form a complicated oil passage, which was difficult to process and increased processing costs. However, there was a problem in that the automatic transmission became expensive.

Purpose of the Invention In view of the above-mentioned points, the unexploded BA is easy and simple to process.
It is also an object of the present invention to provide a structure that can reliably lubricate friction elements.

SUMMARY OF THE INVENTION To achieve this object, the present invention provides an automatic transmission in which automatic transmission is performed by selectively operating various friction elements in a transmission case using pressure oil from a control valve. a portion of the transmission case above at least one of the various friction elements is cut out to form a lubrication window, and leaked oil from the control valve flows down through the lubrication window to reduce the friction of at least one of the friction elements. It is characterized by a structure that lubricates the elements.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 shows the main parts of an automatic transmission having a friction element lubrication structure according to an embodiment of the present invention. 1 is the transmission case,
2 is a side cover attached to the transmission case 1 via a gasket 31; 3 is an input shaft; 4 is a side cover attached to the transmission case 1 via a gasket 31;
5.6 is an output gear rotatably provided coaxially with this human-powered shaft 3, and 5.6 is a planetary gear set coaxially provided with the input shaft 3, respectively.

In the planetary gear set 5, a band brake (not shown)
The sun gear 7 is appropriately fixed, the planetary gear carrier 8 can be appropriately connected to the human shaft 3 by a clutch (not shown), and the internal gear 1o is connected to the transmission case 1 via a one-way clutch 9, and the internal gear 1o is connected to the planetary gear set 6. It is coupled to the planetary gear carrier 11. In the planetary gear set 6, a sun gear 12 is connected to the input shaft 3, a gradation gear carrier 11 is spline connected to the output gear 4, and an internal gear 13 is connected to the planetary gear carrier 8 of the planetary gear set 5 via a clutch 14. Can be combined. For this purpose, the drum 15 of the clutch 14 is drivably coupled via an inner race 16 of the one-way clutch 9 to a single planetary gear carrier 8 . The clutch 14 has a clutch pack 17 between the internal gear 13 and the drum 15, in which plates are arranged alternately on the gears and the drum 15 through spline fitting seams.

The clutch 14 is operated by a piston 18 that is fitted into the drum 15 and forms a hydraulic chamber 19 between the piston 18 and the drum 15, and a return spring 20 that presses the piston 18 against pressure oil. Note that the drum 15 is rotatably supported by a bearing retainer 21, and this retainer 21 is attached to the transmission case 1 to function as a bearing support member for the output gear 4.

The brake 22 and the transformer radially outward of the clutch 14 are housed in the tension case 1 . This brake 2
2 appropriately fixes the planetary gear carrier 8 of the planetary gear set 5 which is drivably connected via the drum 15 and the inner race 16. For this purpose, the brake 22 has a brake pack 23 having plates spline-fitted alternately on the inner circumferential surface of the transformer case I and the inner circumferential surface of the drum 15.

The brake 22 is actuated by a piston 24 which is fitted into the trans-bension case l and forms a hydraulic chamber 27 between it and the case l, and by a return spring 25 which presses the piston 24 into position. Note that a hydraulic pressure supply path for supplying pressure oil to the piston 24 is not shown for simplicity.

control valve 26 h lance transmission case l
A cover 28 covers the control valves 26 disposed on the upper part of the control valve 26 so as to close the openings thereof.

In the present invention, the lubrication structure for the friction elements of the automatic transmission arranged as described above is constructed as follows. The oil leaking from the control valve 26 is disposed in the transmission case 1 and flows into the brake pack 23 (in this embodiment, the brake bag 23), and A lubrication window 29 is formed in the upper part of the transmission case 1. With this kind of structure, the 4 from the control valve
Since the 1'L oil always flows down to the brake pack 28, it can be reliably lubricated.

Effects of the Invention In the friction element 44'j sliding structure of the automatic transmission of the present invention, leakage oil from the control valve flows down through the lubrication window formed in the transmission case, and is structured to cause various friction confections to slide. Therefore, as is customary, we have set up a complicated old-fashioned route.

You can reliably lubricate without any problems. Further, processing is easy because it is sufficient to form a lubrication window by cutting out the entire -=t+ portion of the trans-bension case on the frictional element to be lubricated. Therefore, automatic transmissions can also be manufactured at a lower cost than conventional ones.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of essential parts of an automatic transmission having a friction element lubrication structure according to the present invention. l...Transition case 2...Zide cover 3...Input shaft 4...Output gear 5.6...Planetary gear set 9...One-way clutch 14...Clutch 15...Clutch drum 17...
Clutch back 18 Clutch actuation piston 19...Clutch actuation hydraulic chamber 20...Return spring 21...Bearing retainer 22...Brake 23...Brake pack 24...
...Brake operating piston 25...Return spring 26...Control valve 27...Brake operating hydraulic chamber 28...Valve cover 29...Lubrication window.

Claims (1)

[Claims] L: In an automatic transmission that performs automatic gear shifting by selectively operating various friction elements in a transmission case using pressure oil from a control pulp, the control valve is disposed above the transmission case, and the control valve is arranged above the transmission case to control the various friction elements. A portion of the transmission case above at least one of the elements is cut out to form a lubrication window, and leaked oil from the control pulp flows down through the lubrication window to lubricate the at least one friction element. The friction element lubrication structure of automatic transmissions is characterized by this.