JP2008082412A - Breather structure of automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a breather structure of an automatic transmission capable of surely preventing reduction in an oil quantity and atmospheric pollution, even when turning and accelerating-decelerating a vehicle. <P>SOLUTION: This breather structure is provided with a housing side first horizontal rib 305a extending in a plate shape in the car body front direction up to the housing side second wall surface 302a side more than a breather plug 40 from a housing side first wall surface 301a, a case side first horizontal rib 305b extending in a plate shape in the car body front direction up to the case side second wall surface 302b side more than the breather plug 40 from a case side first wall surface 301b, and a vertical rib 306 for partitioning a case side partition chamber 303b of an upper side partition chamber 303 in the car body longitudinal direction, by contact with the extending end of the case side first horizontal rib 305b, by extending tabularly downward from a position nearer to the case side second wall surface 302b side than the breather plug 40. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a breather structure for an automatic transmission, and more particularly to measures for reliably preventing a decrease in oil amount and atmospheric pollution when a vehicle turns.

  In general, a breather mechanism is provided in an automatic transmission mounted on a vehicle such as an automobile. This breather mechanism eliminates the pressure difference between the inside and outside by releasing the inside air through the breather plug when the pressure inside the case of the automatic transmission becomes higher than the outside pressure. Oil leakage is prevented for lubrication.

  However, the oil mist generated inside the case may be discharged together with the air when the air is released by the above-described breather mechanism, so that the amount of oil is reduced and the atmosphere (air around the case; the same applies hereinafter). There are concerns about contamination.

Therefore, conventionally, a breather chamber through which air discharged through the breather plug passes is provided inside the case of the automatic transmission, and between the facing surfaces facing each other in the breather chamber, the one facing surface to the other When the air containing oil mist passes between the partition walls by alternately projecting a plurality of partition walls extending from one facing surface to the other facing surface from different positions in the vertical direction, It is known that oil is attached to the partition wall and only the air from which the oil mist has been removed is discharged, while the oil attached to the partition wall flows downward by its own weight and is collected (for example, , See Patent Document 1).
Japanese Utility Model Publication No. 3-19160

  By the way, the oil used for lubrication or the like in the case of the automatic transmission foams in the vicinity of the oil surface including air. In that case, when the plurality of partition walls protrude in different directions (from one facing surface and the other facing surface) alternately from different positions in the vertical direction, as in the above-described conventional one, they enter between the partition walls. If the oil level inclines when the vehicle is turning or accelerating / decelerating, the foamed oil is gradually guided to the vicinity of the breather plug (high place) through the partition wall. It will stay near the plug. Therefore, if the oil level is inclined during the next turn or acceleration / deceleration, the breather plug may be immersed in the oil.In this case, when the air is released by the breather mechanism during the vehicle turning or acceleration / deceleration, Oil is discharged to the outside together with air, resulting in a decrease in the amount of oil and atmospheric pollution.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an automatic transmission that can reliably prevent a decrease in the amount of oil and contamination of the atmosphere even when the vehicle is turning or accelerating / decelerating. It is to provide a breather structure.

  In order to achieve the above object, the present invention is based on a breather structure of an automatic transmission provided with a breather mechanism that is disposed at the upper part of the case and communicates the inside and outside of the case. A breather plug is provided on the upper surface of the breather chamber and exhausts the air inside the case to the outside, and a breather chamber is provided in the case and through which the air discharged from the breather plug passes. Then, the breather chamber extends in a flat plate shape from one of the two opposed surfaces facing each other in the lateral direction to the other opposed surface side of the breather plug, and includes the breather plug. A first partition wall that divides the space from the lower space in the vertical direction, and the first partition wall that extends downward in a flat plate shape from the upper surface of the breather chamber corresponding to the other facing surface side of the breather plug. And a second partition wall that abuts the extended end of the breather plug installation side portion of the upper space and partitions the breather plug installation side portion of the upper space from both opposing surface directions.

  Due to this specific matter, the breather plug provided on the upper surface of the breather chamber is partitioned from the lower space by a first partition wall extending in a flat plate shape from one opposing surface to the other opposing surface side of the breather plug. And a second partition wall that extends in a flat plate shape below the upper surface of the breather chamber corresponding to the other facing side of the breather plug and contacts the extended end of the breather plug installation side portion of the first partition wall Is provided at the breather plug installation side portion of the upper space partitioned from both opposing surface directions with respect to the other opposing surface side portion which is on the other opposing surface side than the second partition wall. The breather plug installation side portion of the first partition wall is not partitioned by the second partition wall, and is opened by an opening portion that opens only above the extension end of the anti-breather plug installation side portion of the first partition wall. It will be in communication with the space. As a result, even if the oil that foams in the lower space when the vehicle turns or accelerates or decelerates tries to move to a high place along with the inclination of the oil level, It becomes difficult to enter the upper space via the opening portion that is not partitioned by the second partition wall, and even if oil enters the upper space, the lower space is quickly entered into the lower space through the opening portion. Will be returned. For this reason, even if the oil level is inclined during the next turn or acceleration / deceleration, the breather plug installed on the breather plug installation site in the upper space will not be immersed in the oil level. Even when air is released by the breather mechanism sometimes, the oil is not discharged to the outside together with the air, and it is possible to reliably prevent the oil amount from being reduced and atmospheric contamination.

  In addition, it extends in a flat plate shape from the other facing surface toward the one facing surface in the lateral direction, contacts the lower end of the second partition wall, and is on the other facing surface side than the second partition wall. When a third partition wall is provided for partitioning the other facing surface side portion up and down, and the third partition wall is positioned below the first partition wall, when the vehicle is turning, acceleration / deceleration, etc. The oil foamed in the lower space moves on the third partition wall as the oil level inclines, and even if the oil tries to move to a higher place, Since there is a step between the partition wall and oil, it is very difficult for oil to enter the upper compartment through the opening. In addition, since the third partition wall is positioned below the first partition wall, the oil surface slope in the lower space is suppressed by the lower surface of the third partition wall, and the oil height is increased. The movement to is effectively suppressed. This makes it possible to effectively prevent oil from entering the upper space.

  Further, when a hanging portion that hangs downward is provided at the extending end of the anti-breather plug installation side portion of the first partition wall adjacent to the breather plug installation side portion of the first partition wall, The horizontal movement of the oil accompanying the inclination of the oil level in the space is suppressed by the contact with the hanging part, and the movement of the oil to the high place is more effectively suppressed, and the upper space It is possible to more effectively prevent the oil from entering the water.

  In short, in short, the first partition wall that partitions the upper space including the breather plug from the lower space in the vertical direction, and the second partition wall that contacts the extended end of the breather plug installation side portion of the first partition wall By installing a breather plug at the location where the breather plug is installed in the upper space divided by the above, let's move to a high place as the oil level in the lower space tilts when the vehicle turns or accelerates or decelerates. It is difficult for the oil to foam to enter the breather plug installation side part of the upper space through the opening part above the extension end of the anti-breather plug installation part of the first partition wall. Even if it intrudes, it quickly returns to the lower space through the opening, preventing the breather plug from being immersed in the oil surface during the next turn or acceleration / deceleration, and the breather mechanism during vehicle turning or acceleration / deceleration Air release by Without the discharge to the outside of the oil caused by the air at the time of Tsu, it is possible to reliably prevent deterioration and atmosphere pollution oil level.

  The best mode for carrying out the invention will be described below with reference to the drawings.

  FIG. 1 shows a partial appearance of a case 10 of an automatic transmission 1 using a breather structure according to an embodiment of the present invention, FIG. 2 is a view of a transaxle housing 11 viewed from the mating surface A direction, and FIG. FIG. 2 is a view of the axle case 12 as viewed from the mating surface A direction, and a transmission mechanism and the like are accommodated in the case 10. The automatic transmission 1 is mounted laterally with respect to a vehicle body.

  The case 10 is configured by joining the transaxle housing 11 and the transaxle case 12 at the mating surface A, and joining the transaxle case 12 and the rear case at the mating surface. Note that a torque converter (not shown) is housed inside the transaxle housing 11, and a speed change mechanism (not shown) is housed inside the transaxle case 12. An oil pan for storing oil is provided at the bottom of the case 10 (transaxle case 12). The oil stored in the oil pan is used as an operating oil for a torque converter, as a lubricating oil for a transmission mechanism, and an actuator (not shown) for contacting and separating friction engagement elements such as a clutch and a brake of the transmission mechanism. ) Is supplied by an oil pump (not shown). The supplied oil is collected through a predetermined oil passage in the torque converter and the actuator, and is collected through the inner wall surface of the case 10 in the transmission mechanism. When the automatic transmission 1 is stopped, the oil in the oil pan needs to have an oil level of a predetermined level or higher, that is, the oil level must be a predetermined level or higher. Need to be replenished. If the amount of oil is insufficient, the torque converter and actuator described above may not work well, and the amount of wear of planetary gear rotating elements (sun gear, planetary gear, carrier, ring gear, etc.) constituting the speed change mechanism may increase. become.

  In the transaxle case 12 shown in FIG. 3, portions 12a and 12b are portions where a main transmission mechanism having an output shaft (not shown) connected to a torque converter, a planetary gear, and the like is disposed, and a portion 12c is a drive A sub-transmission mechanism having a pinion (not shown) is provided, and a portion 12d is a part provided with a differential mechanism (not shown). Further, in the transaxle housing 11 shown in FIG. 2, portions 11a and 11b are portions where a main transmission mechanism having an output shaft and a planetary gear connected to a torque converter is disposed, and a portion 11c has a drive pinion. The sub-transmission mechanism is provided, and the portion 11d is a portion where the differential mechanism is provided.

  In the vicinity of the mating surface A in the upper part of the transaxle case 12 constituting a part of the case 10, a breather mechanism 20 which is a characteristic part of the present invention is disposed. The breather mechanism 20 is disposed above the portion 12c in FIGS. 4 is an enlarged view of the breather mechanism on the transaxle case side in FIG. 3, and FIG. 5 is an enlarged view of the breather mechanism on the transaxle housing side in FIG. FIGS. 6 and 7 are a perspective view and a side view schematically showing the entire configuration of the breather mechanism 20 in a state where the transaxle case and the transaxle housing are combined on the respective mating surfaces A. That is, the entire breather mechanism 20 is configured by aligning the transaxle case 12 shown in FIG. 4 and the transaxle housing 11 shown in FIG.

  As shown in FIGS. 4 to 7, the breather mechanism 20 is provided on the upper surface of the breather chamber 30 and discharges the air inside the case 10 to the outside, as shown in FIG. And a breather chamber 30 through which the air discharged from the breather plug 40 passes.

  The breather chamber 30 is formed across the transaxle housing 11 and the transaxle case 12. In the following description, the transaxle housing 11 and the transaxle case 12 are collectively referred to as a case 10.

  The breather chamber 30 has a first wall surface 301 (one facing surface) and a second wall surface 302 (the other facing surface) facing each other in the longitudinal direction of the vehicle body in the case 10. The first wall surface 301 located on the rear side of the vehicle body includes a housing side first wall surface 301a provided on the transaxle housing 11 side and a case side first wall surface 301b provided on the transaxle case 12 side. The housing 11 and the transaxle case 12 are configured by matching the respective mating surfaces A. The second wall surface 302 located on the front side of the vehicle body includes a housing-side second wall surface 302a provided on the transaxle housing 11 side and a case-side second wall surface 302b provided on the transaxle case 12 side. The axle housing 11 and the transaxle case 12 are configured to match each other at the mating surface A. The breather chamber 30 has an upper compartment 303 as an upper space that extends from the first wall surface 301 toward the second wall surface 302 side of the breather plug 40 toward the second wall surface 302 toward the front of the vehicle body and includes the breather plug 40. A first horizontal rib 305 as a first partition wall that projects from the vertical direction with respect to a lower compartment 304 as a lower space is projected. The first lateral rib 305 extends in a flat plate shape from the housing-side first wall surface 301a to the housing-side second wall surface 302a side of the breather plug 40 toward the front of the vehicle body, and serves as the transaxle housing 11 side of the upper compartment 303. From the housing side first lateral rib 305a that vertically divides the side compartment 303a with respect to the housing side compartment 304a on the transaxle housing 11 side of the lower compartment 304, and from the case side first wall surface 301b from the breather plug 40 Also, the case-side compartment 303b, which extends in a flat plate shape toward the front side of the vehicle body toward the case-side second wall surface 302b and is on the transaxle case 12 side of the upper compartment 303, is connected to the transaxle case 12 side of the lower compartment 304. Case-side first horizontal rib that divides up and down with respect to the case-side compartment 304b It consists of a 05b, and is configured by combining the transaxle housing 11 and the transaxle case 12 with the respective mating surface A. The tips of the first lateral ribs 304 (the housing side first lateral rib 305a and the case side first lateral rib 305b) are extended to a position closer to the second wall surface 302 side than the breather plug 40. That is, the breather chamber 30 is connected to the first wall surface side portion (one facing surface side portion) that is closer to the first wall surface 301 than the later-described vertical rib 306 by the first horizontal rib 305, that is, the breather plug from the first wall surface 301. The part from 40 to the second wall surface 302 side is partitioned into upper and lower compartments 303 and 304. In this case, the breather plug 40 is provided on the upper surface 121 of the transaxle case 12 in the breather chamber 30.

  In addition, the upper surface 121 of the transaxle case 12 in the breather chamber 30 extends downward from a position closer to the case side second wall surface 302b than the breather plug 40 in a flat plate shape, and the case side first lateral rib 305b extends. A vertical rib 306 is protruded as a second partition wall that abuts the end and partitions the case-side compartment 303b of the upper compartment 303 in the vehicle front-rear direction (both opposing surfaces). In this case, the breather plug 40 is installed on the upper surface 121 of the case side compartment 303b of the upper compartment 303 partitioned by the longitudinal ribs 306 in the longitudinal direction of the vehicle body. The vertical rib 306 extends slightly below the contact position with the extended end of the case-side first horizontal rib 305b.

  The breather chamber 30 extends in a flat plate shape from the case-side second wall surface 302b toward the case-side first wall surface 301b in the rearward direction of the vehicle body and comes into contact with the extending end (lower end) of the vertical rib 306. A second lateral rib 307 is provided as a third partition wall that vertically divides a case side second wall surface side portion (the other facing surface side portion) that is closer to the case side second wall surface 302b than the rib 306. The second lateral rib 307 is located below the first lateral rib 305.

  Further, a drooping portion 308 that hangs downward is provided at the extending end of the housing-side first horizontal rib 305 a adjacent to the case-side first horizontal rib 305 b that contacts the vertical rib 306. The lower end of the drooping portion 308 is drooping to substantially the same position as the extending end (lower end) of the vertical rib 306.

  Therefore, in the above embodiment, the breather plug 40 provided on the upper surface 121 of the transaxle case 12 in the breather chamber 30 is formed in a flat plate shape from the first wall surface 301 to the second wall surface 302 side of the breather plug 40 toward the front of the vehicle body. The first transverse rib 305 extends to the lower compartment 304 and is below the upper surface 121 of the transaxle case 12 in the breather chamber 30 corresponding to the case side second wall surface 302b side of the breather plug 40. The longitudinal ribs 306 that extend in a flat plate shape and come into contact with the extending ends of the case-side first lateral ribs 305b are arranged in the longitudinal direction of the vehicle body with respect to the case-side second wall surface side portion that is closer to the case-side second wall surface 302b. Since it is provided in the case side compartment 303b of the upper compartment 303 partitioned from the direction, the upper compartment 3 The third case-side compartment 303b opens only above the extension end of the housing-side first lateral rib 305b of the first lateral rib 305 (the side of the longitudinal rib 306) that is not partitioned by the longitudinal rib 306. The opening portion 309 communicates with the lower compartment 304. As a result, even if the oil foamed in the lower compartment 304 is moved to a high place along with the inclination of the oil level when the vehicle is turning or accelerating / decelerating, the oil that is going to move to the high place is not opened. It becomes difficult to enter the upper compartment 303 through the portion 309 (opening portion not partitioned by the vertical ribs 306), and even if oil enters the upper compartment 303, it does not pass through the opening portion 309. It is promptly returned to the lower compartment 304. Therefore, even if the oil level is inclined during the next turn or acceleration / deceleration, the breather plug 40 installed in the case-side compartment 303b of the upper compartment 303 is not immersed in the oil surface, and the vehicle is turning. Even if air is released by the breather mechanism 20 during acceleration / deceleration, the oil is not discharged to the outside together with the air, so that a decrease in the amount of oil and atmospheric contamination can be reliably prevented.

  Moreover, it extends in a flat plate shape from the case-side second wall surface 302b toward the case-side first wall surface 301b in the rearward direction of the vehicle body and comes into contact with the extending end (lower end) of the vertical rib 306. The second lateral rib 307 is provided to vertically divide the case side second wall surface side portion which is the second wall surface 302b side, and the second lateral rib 307 is positioned below the first lateral rib 305, so that the vehicle The oil bubbled in the lower compartment 304 at the time of turning or acceleration / deceleration will move onto the second lateral rib 307 along with the inclination of the oil surface, and the oil will move to a higher place. However, since there is a step between the second lateral rib 307 and the first lateral rib 305 (the housing side first lateral rib 305b and the case side first lateral rib 305b), the oil moves to a high place. Effectively suppressed It will be. In addition, since the second lateral rib 307 is positioned below the first lateral rib 305, the oil surface inclination in the lower compartment 304 is suppressed by the lower surface of the second lateral rib 307. Therefore, the movement of the oil to a high place is effectively suppressed. In addition, since a hanging portion 308 that hangs downward is provided at the extending end of the housing-side first lateral rib 305b, the horizontal movement of the oil accompanying the inclination of the oil surface in the lower compartment 304 is prevented. The contact with the hanging portion 308 is suppressed, and the movement of oil to a high place is more effectively suppressed. This is very advantageous in preventing oil from entering the upper compartment 303.

  In addition, this invention is not limited to the said embodiment, The other various modifications are included. For example, in the above embodiment, the first wall surface 301 is provided on the rear side of the vehicle body and the second wall surface 302 is provided on the front side of the vehicle body so as to face each other, but the first wall surface is on the front side of the vehicle body and the second wall surface is on the rear side of the vehicle body. They may be provided on the sides and face each other. Alternatively, the first wall surface may be provided on either the left or right side of the vehicle body, and the second wall surface may be provided on either the left or right side of the vehicle body so as to face each other.

It is a side view showing a part appearance of a case of an automatic transmission provided with a breather structure concerning an embodiment of the present invention. It is the figure which looked at the transaxle housing from the mating surface A direction. It is the figure which looked at the transaxle case from the mating surface A direction. FIG. 4 is an enlarged view of a breather mechanism on the transaxle case side in FIG. 3. FIG. 3 is an enlarged view of a breather mechanism on the transaxle housing side in FIG. 2. It is a perspective view which shows a breather mechanism typically. It is the side view seen from the 2nd wall surface side which shows a breather mechanism typically.

Explanation of symbols

1 automatic transmission 10 case 11 transaxle housing 12 transaxle case 121 upper surface (the upper surface of the case)
20 Breather mechanism 30 Breather chamber 301 First wall surface (one facing surface)
302 2nd wall surface (the other facing surface)
303 Upper compartment (upper space)
304 Lower compartment (lower space)
305 1st lateral rib (1st partition wall)
306 Vertical rib (second partition wall)
307 Second lateral rib (third partition wall)
308 Drooping 40 Breather plug

Claims (3)

In a breather structure of an automatic transmission provided with a breather mechanism that is disposed at the top of the case and communicates the inside and outside of the case,
The breather mechanism is
A breather plug which is provided on the upper surface of the breather chamber and discharges the air inside the case to the outside;
A breather chamber provided in the case, through which air discharged from the breather plug passes,
The breather room is
The upper space including the breather plug is defined as a lower space extending in a flat plate shape from one of the two facing surfaces facing each other in the lateral direction to the other facing surface side of the breather plug. A first partition wall for partitioning from above and below,
Extending in a flat plate shape below the upper surface of the breather chamber corresponding to the other opposing surface side of the breather plug, abuts with the extended end of the breather plug installation side portion of the first partition wall, and A breather structure for an automatic transmission, comprising: a second partition wall that partitions a breather plug installation side portion from both opposing surface directions. In the breather structure of the automatic transmission according to claim 1,
The other facing surface extends from the other facing surface toward the one facing surface in a flat plate shape and contacts the lower end of the second partition wall, and is located on the other facing surface side of the second partition wall. A third partition wall is provided to vertically divide the opposing surface side part;
The breather structure for an automatic transmission, wherein the third partition wall is located below the first partition wall. In the breather structure of the automatic transmission according to claim 1 or 2,
An automatic is characterized in that a drooping portion that hangs downward is provided at an extension end of the anti-breather plug installation side portion of the first partition wall adjacent to the breather plug installation side portion of the first partition wall. The breather structure of the transmission.

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