JP5480873B2 - Vehicle transmission - Google Patents

Description

  The present invention relates to a vehicle transmission, and more particularly to an oil lubrication structure for a vehicle transmission.

  The automatic transmission includes a transmission mechanism, a differential mechanism, and the like housed in a transmission case. The automatic transmission shifts an output input from a drive source such as an internal combustion engine by a speed change mechanism and outputs it from a final gear of the differential mechanism. An oil pan for storing oil used for lubrication and control is attached to the lower part of the transmission case.

  Lubrication of the speed change mechanism and the differential mechanism is performed not only by forced lubrication by an oil pump but also by oil scattered and scattered by the rotation of a final gear (differential gear) of the differential mechanism. The oil used for lubrication returns to the oil pan chamber (oil chamber).

  The differential mechanism chamber in which the final gear is disposed is disposed adjacent to the oil pan chamber in the horizontal direction. The oil stored in the oil pan chamber is supplied to the differential mechanism chamber, and the oil collected at the bottom of the differential mechanism chamber is swept up by the rotation of the final gear and used for lubrication.

  For example, in Patent Document 1, an opening (return port) for returning the oil supplied to the transmission mechanism to the oil pan chamber is formed on the upper surface of the oil pan chamber, and the differential mechanism chamber and the oil pan chamber are partitioned. A vehicle transmission in which one oil passage (communication passage) is formed in a partition wall is disclosed.

Japanese Patent No. 4279885

  However, in the vehicle transmission disclosed in Patent Document 1, the amount of oil supplied from the oil pan chamber to the differential mechanism chamber is determined by the cross-sectional area of the oil passage.

  Therefore, if the oil cross-sectional area is set to be large in accordance with the state where the amount of oil supplied for lubrication is large and the amount of oil supplied from the oil pan chamber to the differential mechanism chamber is increased, less oil is supplied for lubrication. In the state, a large amount of oil accumulates at the bottom of the differential mechanism chamber. As a result, the amount of oil that is swung by the final gear due to the viscosity of the oil increases and the stirring resistance of the final gear increases, resulting in a problem of deterioration in fuel consumption.

  On the other hand, if the cross-sectional area of the oil passage is set to be small in accordance with the state where the oil supplied for lubrication is small, and the oil supplied from the oil pan chamber to the differential mechanism chamber is reduced, the oil collected at the bottom of the differential mechanism chamber is Decrease. However, when a large amount of oil is used for lubrication, there is a problem that the oil accumulated at the bottom of the differential mechanism chamber is insufficient and sufficient lubrication cannot be performed.

  As described above, the vehicular transmission disclosed in Patent Document 1 has a problem that it is difficult to provide an oil passage so that reduction in stirring resistance and securing of lubrication can be satisfactorily achieved.

  In view of the above, an object of the present invention is to provide a vehicular transmission capable of satisfactorily achieving reduction in stirring resistance and ensuring lubrication.

The present invention includes a differential gear that is rotated by transmission of power from a speed change mechanism, a differential mechanism chamber in which the differential gear is disposed, a differential mechanism chamber and a partition wall that are disposed adjacent to each other in a horizontal direction through a partition wall, An oil chamber for storing; a return port provided at an upper portion of the oil chamber for returning the oil accumulated at the bottom of the differential mechanism chamber and pumped up by rotation of the differential gear to the oil chamber; and provided in the partition wall A first communication passage that communicates the differential mechanism chamber and the oil chamber; and a second communication passage that is provided above the first communication passage in the partition and communicates the differential mechanism chamber and the oil chamber. and communication path is formed in a substantially upper half of the surface and substantially covers the side semicylindrical the differential gear, The baffle plate that rectifies the oil pumped up by the rotation of the differential gear, and the notched portion and the slope provided in the baffle plate, accumulated in the differential mechanism chamber and pumped up by the rotation of the differential gear And an introduction path for guiding the gas to the return port .

  According to the present invention, the oil level of the oil stored in the oil chamber becomes low when the oil returning to the oil chamber is small, such as when the differential gear rotates at a low speed and the amount of oil swept up is small. Oil is supplied to the differential mechanism chamber only through the first communication path.

  Therefore, oil exceeding the required amount does not accumulate at the bottom of the differential mechanism chamber, so the amount of oil that is driven by the differential gear due to the viscosity of the oil is reduced, the stirring resistance of the differential gear is reduced, and stirring loss is reduced. It is suppressed. Therefore, fuel consumption is improved.

  On the other hand, when there is a lot of oil returning to the oil chamber, such as when the differential gear rotates at high speed and there is a lot of oil being swept up, the oil level of the oil stored in the oil chamber becomes high, and not only the first communication path Oil is also supplied from the oil chamber to the differential mechanism chamber via the second communication path.

  Therefore, the amount of oil supplied to the differential mechanism chamber is increased, and there is no possibility that the oil accumulated at the bottom of the differential mechanism chamber is insufficient. Thereby, insufficient lubrication of each part lubricated by the oil lifting of the differential gear can be reliably prevented.

As described above, according to the present invention, it is possible to always ensure the minimum amount of oil at the bottom of the differential mechanism chamber and to reduce the stirring resistance of the differential gear.
Further, the oil that has been lifted up by the differential gear and provided for lubrication in each part of the automatic transmission can be quickly returned to the oil chamber through the return port by the introduction path. Therefore, it is possible to reduce the risk of oil shortage in the oil chamber.

  In the present invention, when the second communication path is provided at a position that is too high, there is a risk that the oil accumulated at the bottom of the differential gear will be insufficient.

  Therefore, it is preferable that the second communication path is provided at a height equal to or lower than the oil level of the oil accumulated at the bottom of the differential mechanism chamber when the rotation of the differential gear is stopped.

  In the present invention, as the differential gear rotates from a low speed to a high speed, the amount of oil returning from the return port to the oil chamber is transferred from the oil chamber to the differential mechanism chamber via the first communication path. It is preferable to change from a state where the amount of oil supplied is less than a large amount.

  In this case, at a certain rotational speed of the differential gear, the amount of oil returning from the return port to the oil chamber is changed from a state where the amount of oil supplied from the oil chamber to the differential mechanism chamber via the first communication path is smaller than a larger amount. Will be.

  As a result, when the differential gear rotates at a lower speed than the certain rotation speed, oil is supplied from the oil chamber to the differential mechanism chamber only through the first communication path, and a necessary amount is supplied to the bottom of the differential mechanism chamber. Since much oil does not accumulate, the agitation resistance of the differential gear is reduced and fuel efficiency is improved.

  On the other hand, when the differential gear rotates at a higher speed than the certain rotation speed, oil is supplied from the oil chamber to the differential mechanism chamber not only through the first communication path but also through the second communication path, and the differential mechanism chamber Therefore, it is possible to reliably prevent insufficient lubrication of each portion lubricated by the oil lifting of the differential gear.

  The certain number of rotations is determined by the structure and material of the speed change mechanism and the differential mechanism, the height positions and cross-sectional areas of the first and second communication paths, the oil viscosity, the oil temperature, and the like. is not.

1 is a schematic side view showing an automatic transmission according to an embodiment of the present invention. A conceptual sectional view for explaining an automatic transmission. The schematic perspective view which shows the state which looked at the main case which attached the baffle plate from the torque converter side. The schematic cross-sectional perspective view which shows the state which looked at the main case which attached the baffle plate from the transmission mechanism side.

  Hereinafter, an automatic transmission 10 according to an embodiment of the present invention will be described with reference to the drawings.

  As schematically shown in FIG. 1, the automatic transmission 10 is configured such that a torque converter 11, a transmission mechanism 12, and a differential mechanism 13 are accommodated in a transmission case 14. Although not shown, the automatic transmission 10 is mounted on a vehicle and shifts the output of a drive source such as an internal combustion engine (engine) to transmit it to the left and right drive wheels.

  As shown in FIG. 2, the speed change mechanism 12 includes a belt-type continuously variable transmission (CVT). The transmission mechanism 12 includes an input shaft 21, a drive pulley shaft 22, a driven pulley shaft 23, and an idle shaft 24 that are provided in parallel to each other.

  A V belt mechanism 25 is provided between the driving pulley shaft 22 and the driven pulley shaft 23. The V belt mechanism 25 includes a driving pulley 26 provided on the driving pulley shaft 22, a driven pulley 27 provided on the driven pulley shaft 23, and a metal V belt 28 wound around these pulleys 26, 27. It consists of and.

  The output from the drive source input from the input shaft 21 via the torque converter 11 (see FIG. 1) is shifted at a continuously variable transmission ratio (ratio) via the V-belt mechanism 25, and the driven pulley shaft 23. Is rotated in the vehicle forward direction or the vehicle reverse direction.

  The differential mechanism 13 includes a hollow differential case (not shown) that is rotatably supported by the transmission case 14, and a final gear (differential gear) 31 that is integrally attached to the differential case. The driven pulley shaft 23, which is the output shaft of the speed change mechanism 12, is connected to the differential mechanism 13 by meshing the final gear 31 with the gear 29 provided on the driven pulley shaft 23. The differential mechanism 13 is disposed below the speed change mechanism 12.

  As shown in FIG. 1, the transmission case 14 includes a main case 41 that houses the transmission mechanism 12 and a converter case 42 that houses the torque converter 11. An oil pan 43 is attached to the lower surface of the main case 41. The oil pan 43 is a sheet metal that is formed into a tray shape. The oil pan 43 stores oil called ATF (Automatic Transmission Fluid).

  As shown in FIGS. 1 and 2, the transmission case 14 includes a converter chamber 51 that houses the torque converter 11, a transmission mechanism chamber 52 that houses the transmission mechanism 12, a differential mechanism chamber 53 that houses the differential mechanism 13, and an oil A bread chamber (oil chamber) (control chamber) 54 is partitioned inside.

  The main case 41 includes a substantially cylindrical outer peripheral wall 41a continuous in the circumferential direction, an intermediate wall 41b (see FIG. 4) that partitions the transmission mechanism chamber 52 and the differential mechanism chamber 53, and a transmission mechanism chamber in the outer peripheral wall 41a. 52 and partition walls 41c and 41d are formed integrally with the differential mechanism chamber 53 side and the oil pan chamber 54 side. The converter case 42 has a cylindrical outer peripheral wall 42a that is continuous in the circumferential direction.

  The partition wall 41 c is formed substantially horizontally and partitions the transmission mechanism chamber 52 and the oil pan chamber 54. The partition wall 41 c is an upper wall of the oil pan chamber 54. A return port (opening) 41e for returning oil from the transmission mechanism chamber 52 into the oil pan chamber 54 is formed in the partition wall 41c so as to penetrate in the vertical direction.

  The partition wall 41d is continuously extended from the end of the outer peripheral wall 41a along the lower portion of the differential mechanism 13 and extends upward in a substantially arc shape so as to be connected to the end of the partition wall 41c. The bread chamber 54 is partitioned. The partition wall 41 d is a side wall of the oil pan chamber 54 on the differential mechanism chamber 53 side. The lowermost part of the outer peripheral wall 41a is located below the lower end part of the partition wall 41d.

  Two communication paths 41f and 41g are formed in the partition wall 41d. These communication passages 41f and 41g are small holes penetrating the partition wall 41d in the horizontal direction, and communicate with the differential mechanism chamber 53 and the oil pan chamber 54 so that oil can freely pass therethrough.

  The two communication passages 41f and 41g are formed at an interval in the vertical direction, and the first communication passage 41f is positioned below the second communication passage 41g. The second communication passage 41g is formed to have a height substantially equal to or lower than the oil level of the oil accumulated at the bottom of the differential mechanism chamber 53 when the vehicle is horizontal and the rotation of the final gear 31 is stopped. ing.

  The main case 41 and the converter case 42 are coupled by being fastened with a bolt (not shown) in a state where the mating surfaces are abutted with each other. By this connection, the differential mechanism 13 is accommodated, and a differential mechanism chamber 53 in which the final gear 31 is disposed is formed. The bottom surface of the main case 41, the partition wall 41 c, and the bottom surface of the converter case 42 are positioned with a gap between them and the side peripheral surface of the final gear 31.

  The speed change mechanism chamber 52 and the differential mechanism chamber 53 are adjacent to each other in a plane orthogonal to the axial direction of the input shaft 21 and communicate with each other. The bottom portion of the differential mechanism chamber 53 is formed at a position lower than the bottom portion of the transmission mechanism chamber 52.

  An oil pan 43 is attached to the lower portion of the main case 41 by fastening with a bolt (not shown). With this attachment, an oil pan chamber 54 is formed in front of the differential mechanism chamber 53. A valve body 61 and an oil strainer 62 are accommodated in the oil pan chamber 54.

  The valve body 61 incorporates a hydraulic control valve that controls the hydraulic pressure when oil in the oil pan chamber 54 is supplied to each part of the automatic transmission 10. The oil strainer 62 removes foreign matters contained in the oil supplied from the oil pan chamber 54 to the valve body 61.

  An oil pump 63 is disposed in the transmission mechanism chamber 52. The oil pump 63 rotates by being driven by the chain from the input shaft 21, pumps oil in the oil pan chamber 54 through the oil strainer 62, and supplies it to each part of the automatic transmission 10.

  As shown in FIGS. 3 and 4, a baffle plate 64 is disposed in the vicinity of the driven pulley shaft 23 and the final gear 31 of the differential mechanism 13. The baffle plate 64 accumulates at the bottom of the differential mechanism chamber 53 and rectifies the oil that has been lifted and scattered by the final gear 31 rotating. In FIG. 3, the shaded portion is the mating surface of the main case 41, and bolt fastening holes and the like are omitted. In FIG. 2, the white arrow indicates the rotation direction of the final gear 31 when the vehicle moves forward.

  In the following description, the front side of the baffle plate 64 means the torque converter 11 side, and the back side means the transmission mechanism 12 side. Moreover, the upper and lower sides of the baffle plate 64 mean the upper and lower sides in the direction of gravity when the baffle plate 64 is assembled to the automatic transmission 10.

  The baffle plate 64 is inserted through the driven pulley shaft 23, the short semi-cylindrical small covering portion 64 a covering the substantially upper half side surface of the driven pulley shaft 23, and the shaft portion of the final gear 31, and the final gear 31. A substantially semi-cylindrical gear cover 64b that covers substantially the upper half of the surface and side surfaces with a minute gap therebetween is continuously formed integrally.

  A cutout 64c is formed on the side surface of the small cover portion 64a. An arc-shaped cut 64d is formed in the small cover portion 64a, the gear cover portion 64b, and the coupling portion.

  Further, on the back surface side of the baffle plate 64, a slope 64e is formed so as to extend obliquely across the baffle plate 64 as a whole and integrally formed with the small cover part 64a and the gear cover part 64b. Specifically, the slope 64e extends in an arc shape on the side of the small covering portion 64a, covers the side surface of the driven pulley 27 with a minute gap, passes under the notch 64c and the notch 64d, and passes through the final gear 31. The upper part of the shaft part extends in an arc shape and extends to the end part of the gear cover part 64b.

  Further, a notch 64f is formed on the side surface of the gear cover 64b slightly below the slope 64e.

  Hereinafter, oil lubrication in the automatic transmission 10 according to the embodiment of the present invention will be described.

  When the valve body 61 and the oil pump 63 operate according to preset operation conditions, the oil in the oil pan chamber 54 is used for lubrication of each part in the automatic transmission 10. The oil used for lubricating each part is returned to the oil pan chamber 54 by flowing down along the inner wall surface of the main case 41, the baffle plate 64, or the like.

  More specifically, the oil swept up by the final gear 31 is received by the baffle plate 64 and, as indicated by an arrow, is sent to the shaft portion of the differential mechanism 13 through the notch 64f, and the final gear 31 has a bearing. Used for lubrication.

  Further, the oil whose scattering is prevented by the portion covering the side surface of the gear cover 64b flows to the back side through the notch 64c, is sent to the shaft portion of the driven pulley 27, and lubricates the bearing of the driven pulley 27 and the like. Provided.

  Further, the oil that has flowed to the back side through the notches 64d and the oil that has been used for lubrication of each part of the transmission mechanism 12 such as the bearing of the driven pulley 27 flows along the back surface of the slope 64e and the baffle plate 64, and returns to the return port. It returns to the oil pan chamber 54 through 41e. In the present embodiment, the oil path A flowing along the slope 64e to the return port 41e corresponds to the introduction path of the present invention.

  In this manner, the oil that has been lifted and scattered by the final gear 31 can be quickly returned into the oil pan chamber 54 by the baffle plate 64. Therefore, it is possible to reduce the risk of oil shortage in the oil pan chamber 54.

  When the final gear 31 is stopped for a long time, the oil level in the differential mechanism chamber 53 is substantially the same as the height of the second communication passage 41g. At this time, since the differential mechanism chamber 53 and the oil pan chamber 54 are communicated with each other through the first communication path 41f, the oil surface heights of the oil in the differential mechanism chamber 53, the oil pan chamber 54, and the oil are equal. ing.

  As the rotational speed of the final gear 31 increases, the oil that is swept up and scattered by the final gear 31 and used for lubrication of each part such as the differential mechanism 13 and the transmission mechanism 12 increases. The oil used for the lubrication returns to the oil pan chamber 54 through the return port 41e and is accumulated.

  Thus, as the rotational speed of the final gear 31 increases, the oil level in the differential mechanism chamber 53 decreases, and the lower end portion of the final gear 31 immersed in the oil decreases. For this reason, the amount of oil that is driven by the final gear 31 due to the viscosity of the oil is reduced, and the stirring resistance of the final gear 31 is reduced, so that stirring loss is suppressed. Therefore, fuel consumption is improved.

  In the state where the final gear 31 rotates at a low speed, less oil is swept up and scattered by the final gear 31 and less oil returns to the oil pan chamber 54 due to lubrication, so that the oil level in the oil pan chamber 54 also decreases. To do. However, since the oil lower than the first communication path 41f is not supplied to the differential mechanism chamber 53, the oil level in the oil pan chamber 54 is always higher than the first communication path 41f, and the first communication path 41f It is located between the height of the second communication passage 41g. As a result, oil is always supplied from the oil pan chamber 54 to the differential mechanism chamber 53 via the first communication path 41f.

  Therefore, the necessary minimum amount of oil is always secured at the bottom of the differential mechanism chamber 53, and there is no possibility that the oil swept up by the final gear 31 will be insufficient. Thereby, insufficient lubrication of each part lubricated by the oil scooping of the final gear 31 can be reliably prevented.

  Note that the height of the first communication path 41f is such that only the oil in the oil pan chamber 54 existing at a position lower than the first communication path 41f satisfies the minimum amount of oil necessary for the oil pump 63. Is set. A suction passage (not shown) connected to the oil pump inlet is disposed at a position lower than the first communication passage 41f.

  In a state where the final gear 31 rotates at a high speed, a lot of oil is swept up and scattered by the final gear 31 and more oil returns to the oil pan chamber 54 due to lubrication, and the oil level in the oil pan chamber 54 increases. Get higher. When the oil level in the oil pan chamber 54 becomes higher than the second communication passage 41g, the differential mechanism from the oil pan chamber 54 not only through the first communication passage 41f but also through the second communication passage 41g. Oil is supplied to the chamber 53.

  Therefore, the amount of oil supplied to the differential mechanism chamber 53 is increased, and there is no possibility that the oil accumulated at the bottom of the differential mechanism chamber 53 is insufficient. Thereby, insufficient lubrication of each part lubricated by the oil scooping of the final gear 31 can be reliably prevented.

  As described above, according to the automatic transmission 10 according to the present embodiment, the minimum necessary oil is secured at the bottom of the differential mechanism chamber 53, the stirring resistance of the final gear 31 is reduced, and the fuel efficiency is improved. It becomes possible to make it.

  Note that the amount of oil returning from the return port 41e to the oil pan chamber 54 at the rotation speed N of the final gear 31 is the amount of oil supplied from the oil pan chamber 54 to the differential mechanism chamber 53 via the first communication path 41f. The state changes from a smaller state to a larger state, and becomes a switching point between the low-speed rotation and the high-speed rotation described above. Such a rotational speed N is determined by the structure and material of the speed change mechanism 12 and the differential mechanism 13, the height positions and cross-sectional areas of the first and second communication passages 41f and 41g, the oil viscosity, the oil temperature, and the like. It is not a constant predetermined value.

  The amount of oil flowing through the two communication passages 41f and 41g can be adjusted by appropriately changing the cross-sectional areas of the communication passages 41f and 41g, and the rotational speed N also changes accordingly. These set values are appropriately determined by the designer and are not particularly limited.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this. For example, although the case where the automatic transmission 10 is a belt-type continuously variable transmission has been described, the vehicle transmission according to the present invention is a continuously variable automatic transmission other than the belt type, a stepped automatic transmission. A manual transmission may be used.

  Moreover, although the case where the two communication paths 41f and 41g are provided in the partition wall 41d has been described, three or more communication paths may be provided in the partition wall 41d. Furthermore, although the case where two holes are formed in the partition wall 41d of the main case 41 to provide the two communication paths 41f and 41g has been described, for example, a hole is formed in the partition wall 41d to provide one communication path, The communication path may be a gap between the partition wall 41d and the oil pan 43.

  DESCRIPTION OF SYMBOLS 10 ... Automatic transmission, 11 ... Torque converter, 12 ... Transmission mechanism, 13 ... Differential mechanism, 14 ... Transmission case, 21 ... Input shaft, 22 ... Drive pulley shaft, 23 ... Driven pulley shaft, 25 ... V belt mechanism, 26 ... Drive pulley, 27 ... Driven pulley, 31 ... Final gear (differential gear), 41 ... Main case, 41a ... Outer wall, 41b ... Intermediate wall, 41c ... Partition, 41d ... Partition, 41e ... Return port, 41f ... First 1 communication path, 41g ... 2nd communication path, 42 ... converter case, 43 ... oil pan, 51 ... converter chamber, 52 ... transmission mechanism chamber, 53 ... differential mechanism chamber, 54 ... oil pan chamber (oil chamber), 61 ... Valve body, 62 ... Oil strainer, 63 ... Oil pump, 64 ... Baffle play , 64a ... Small covering portion, 64b ... gear covering portion, 64c ... notch, 64d ... cut, 64e ... slope, 64f ... cutout, A ... path (introduction passage).

Claims (3)

A differential gear that is rotated by transmission of power from the transmission mechanism;
A differential mechanism chamber in which the differential gear is disposed;
An oil chamber that is disposed adjacent to the differential mechanism chamber in a horizontal direction via a partition wall and stores oil;
A return port provided at the top of the oil chamber for returning the oil accumulated at the bottom of the differential mechanism chamber and swept up by the rotation of the differential gear to the oil chamber;
A first communication path provided in the partition wall and communicating the differential mechanism chamber and the oil chamber;
A second communication path that is provided above the first communication path in the partition wall and communicates the differential mechanism chamber and the oil chamber ;
A baffle plate that covers the substantially upper half surface and side surfaces of the differential gear, is formed in a substantially semi-cylindrical shape, and rectifies the oil that is swept up by the rotation of the differential gear;
A vehicle comprising: a notch provided in the baffle plate and a slope; and an introduction path for collecting oil collected in the differential mechanism chamber and swept up by rotation of the differential gear to the return port. Transmission. It said second communication path, to claim 1, wherein said be provided in the oil level height of the height of the oil accumulated in the bottom portion of the differential mechanism chamber when the rotation of the differential gear is stopped The vehicle transmission as described. As the differential gear rotates from low speed to high speed, the amount of oil returning from the return port to the oil chamber is greater than the amount of oil supplied from the oil chamber to the differential mechanism chamber via the first communication path. The vehicle transmission according to claim 1 or 2 , wherein the vehicle shifts from a small state to a large state.

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