Power transmission device

Abstract

The present invention provides a power transmission device. The power transmission device comprises: a baffle (4) including a main body (5), a cover (8, 9), and a sealing member (88, 98); a final gear (25) and a driven sprocket (DS) arranged in a storage chamber (Sa, Sb) of the baffle (4); an oil pump (OP) as a supply source of lubricating oil (OL); and an oil pan (16). At least one of the main body (5), the cover (8, 9), and the sealing member (88, 98) contains a material that shrinks as the temperature of the oil (OL) decreases. The baffle (4) is dimensioned such that when the temperature of the oil (OL) is above a predetermined oil temperature, the gaps (CL1, CL2) are sealed by the sealing member (88, 98), and when the temperature is below the predetermined oil temperature, a gap (CL') is formed. The gaps (CL1, CL2) are gaps between the inner periphery of the outer wall portion (62, 72) of the main body portion (5) and the base portion (80) of the cover portion (8) and the base portion (90) of the cover portion (9).

Description

Technical Field

[0001] The present invention relates to a power transmission device. Background Art

[0002] Patent Document 1 discloses a structure in which a pair of baffles is used to surround a sprocket as a rotating member.

[0003] Patent Document 2 discloses a structure in which a pair of baffles is used to surround a gear as a rotating member.

[0004] The retainer plate of Patent Document 2 is provided to surround the final gear included in the differential device.

[0005] In a power transmission device having such a final gear, in order to reduce the stirring resistance caused by the rotating member (final gear) and improve fuel economy, it is generally preferred to suppress the amount of oil intrusion into the space surrounded by the pair of baffles.

[0006] On the other hand, when the oil temperature is extremely low, an exceptional situation occurs. That is, first, when the power transmission device is viewed as a whole, oil returns from each passage to the oil reservoir (oil pan) which is the suction source of the oil pump. Then, when the oil temperature drops, the viscosity of the oil increases and the fluidity decreases.

[0007] Therefore, when the oil temperature decreases, the return of oil to the oil reservoir (oil pan) serving as the suction source of the oil pump slows down in the power transmission device as a whole.

[0008] Therefore, it is necessary to promote the return of oil to the oil storage tank when the oil temperature is lowered.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: (Japanese) Patent Publication No. 2012-102818

[0012] Patent Document 2: (Japan) Patent No. 5844019 Summary of the invention

[0013] The present invention is a power transmission device having:

[0014] A baffle portion, comprising: a pair of baffles, and a sealing member disposed in a region between the pair of baffles;

[0015] a rotating member disposed in a rotating member chamber, which is a space surrounded by the baffle portion;

[0016] an oil pump serving as a supply source of lubricating oil supplied to the rotating component;

[0017] an oil pan storing oil serving as a suction source for the oil pump;

[0018] One of the pair of baffles, the other of the pair of baffles, or at least one of the sealing member is formed of a material that shrinks as the oil temperature decreases.

[0019] The baffle portion is set to a size such that the sealing member seals a region between the pair of baffles when the oil temperature is equal to or higher than a predetermined temperature, and a gap is formed in the region between the pair of baffles when the oil temperature is lower than the predetermined temperature.

[0020] According to the present invention, when the oil temperature decreases, the return of oil to the oil storage tank can be promoted. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a diagram illustrating the main components of a gearbox.

[0022] Figure 2 It is a diagram for explaining the arrangement of the baffle plate of the transmission.

[0023] Figure 3 It is a figure explaining a baffle.

[0024] Figure 4 It is a diagram for explaining the main body of the baffle.

[0025] Figure 5 It is a figure explaining the cover part of a baffle.

[0026] Figure 6 It is a figure explaining the cover part of a baffle.

[0027] Figure 7 It is a figure explaining the effect|action of a baffle. DETAILED DESCRIPTION

[0028] Hereinafter, an embodiment of the present invention will be described by taking as an example a case where the power transmission device is an automatic transmission 1 for a vehicle.

[0029] Figure 1 1 is a diagram for explaining main components of the transmission 10 , and is a diagram for explaining the periphery of a housing portion 15 of a differential device of the transmission 10 of the automatic transmission 1 .

[0030] Figure 1 (a) is a diagram showing the transmission 10 as viewed from the torque converter (not shown) side. Figure 1 (b) Yes Figure 1 Magnified view of area B in (a).

[0031] It should be noted that in Figure 1 In FIG. 1 , the joint surface between the transmission 10 and the torque converter housing (not shown) and the end surface of the outer wall portion 62 of the baffle plate 4 on the front side of the paper are indicated by hatching.

[0032] Figure 2 It is a diagram for explaining the arrangement of the baffle plate 4 of the transmission case 10 . Figure 2 (a) is along Figure 1 (a) is a diagram showing a baffle 4 cut along line AA. Figure 2 (b) is along Figure 1 (b) is a diagram showing the baffle 4 cut along the CC line.

[0033] In the following, Figure 1 The positional relationship of the main components of each structure is explained based on the configuration of the gearbox 10 in FIG.

[0034] In the following description, the "upper side (upper part)" indicates the upper side in the direction of the plumb line VL based on the setting state of the automatic transmission, and the "lower side (lower part)" indicates the lower side in the direction of the plumb line based on the setting state of the automatic transmission.

[0035] like Figure 1 As shown, a differential device housing portion 15 is provided at the lower portion of the transmission case 10. The housing portion 15 opens on the torque converter side (front side in the drawing) which is not shown.

[0036] The differential case 20 is rotatably supported at the center of the housing portion 15. A final gear 25 formed in an annular shape when viewed from the direction of the rotation axis X1 of the differential case 20 is fixed to the outer periphery of the differential case 20.

[0037] A tooth portion 250 is formed on the outer periphery of the final gear 25 over the entire circumference in the circumferential direction around the rotation axis X1 .

[0038] The tooth portion 250 of the final gear 25 is inclined at a predetermined angle with respect to the rotation axis X1 when viewed from the radial direction of the rotation axis X1. The final gear 25 is a helical gear having the tooth portion 250 inclined thereon.

[0039] The reduction gear 35 is located above the final gear 25 . The teeth 35 a on the outer periphery of the reduction gear 35 mesh with the teeth 250 of the final gear 25 .

[0040] In the transmission case 10, the reduction gear 35 is rotatably provided around the rotation axis X2. The rotation axis X2 of the reduction gear 35 is located above the rotation axis X1 of the final gear 25 and is provided in parallel with the rotation axis X1.

[0041] The reduction gear 35 is rotated about the rotation axis X2 by the output rotation of the speed change mechanism (not shown). Therefore, the final gear 25 meshed with the reduction gear 35 on the outer periphery rotates about the rotation axis X1 by the rotational driving force transmitted from the reduction gear 35 .

[0042] When the vehicle equipped with the automatic transmission 1 travels forward, the final gear 25 rotates in the clockwise direction CW (forward direction) in the figure.

[0043] When viewed from the direction of the rotation axis X1 , the peripheral wall portion 11 of the transmission case 10 is formed in an arc shape in which a region near the final gear 25 surrounds the outer periphery of the final gear 25 .

[0044] A plurality of screw holes 12 are provided at intervals in the circumferential direction in the peripheral wall portion 11. An end surface 11a of the peripheral wall portion 11 on the front side of the paper plane serves as a joining surface with a torque converter case (not shown) surrounding a torque converter (not shown).

[0045] In the transmission case 10, a wall portion 13 is provided inside the peripheral wall portion 11 to cover the side surface of the final gear 25. Figure 2 As shown in (a), the wall portion 13 is located on the left side of the final gear 25 in the figure and is provided in a direction along the side surface 25 a of the final gear 25 .

[0046] The transmission case 10 is provided with a baffle 4 (body 5, cover 8, cover 9) (see Figure 1 , Figure 2 , Figure 3 ).

[0047] The baffle plate 4 is provided across a region where the final gear 25 is provided and a region where the driven sprocket DS is provided in the transmission case 10 .

[0048] Figure 3 4 (main body 5, cover 8, cover 9). Figure 3 In FIG. 1 , the final gear 25 is indicated by a virtual line, and the main components of the shutter 4 (main body 5 , cover 8 , cover 9 ) are shown with their positions offset from the final gear 25 in the direction of the rotation axis X1 .

[0049] Figure 4 It is a diagram for explaining the main body 5 of the baffle 4. Figure 4 (a) is a diagram showing the main body 5 as viewed from the direction of the rotation axis X1. Figure 4 (b) Yes Figure 4 (a) AA cross-sectional view. Figure 4 (c) Yes Figure 4 (a) BB cross-sectional view.

[0050] It should be noted that in Figure 4 In (a), a portion of the driven sprocket DS is represented by a virtual line. Figure 4 In (b), the final gear 25 is represented by a virtual line. Figure 4 In (c), the driven sprocket DS and a part of the drive shaft SH are indicated by virtual lines.

[0051] like Figure 3 As shown, the baffle 4 includes a main body 5 fixed to the transmission case 10, a cover 8 fixed to the torque converter housing (not shown), and a cover 9 fixed to the main body 5. In this embodiment, the baffle 4 is formed of a polymer material having a large linear expansion coefficient at low temperatures.

[0052] When the cover 8 is assembled to the main body 5, a storage chamber Sa (rotating body storage chamber) for the final gear 25 is formed between the main body 5 and the cover 8 (see Figure 2 (a)).

[0053] When the cover 9 is assembled to the main body 5, a housing chamber Sb (rotating body housing chamber) for the driven sprocket Ds is formed between the main body 5 and the cover 9 (see Figure 2 (b)).

[0054] like Figure 4 As shown in (a), the main body 5 of the baffle plate 4 includes a first cover portion 6 that covers the side surface of the final gear 25 and a second cover portion 7 that covers the side surface of the driven sprocket DS.

[0055] The first cover portion 6 and the second cover portion 7 are integrally formed by resin molding.

[0056] The first cover portion 6 has a plate-shaped base portion 60 when viewed from the direction of the rotation axis X1.

[0057] The base portion 60 extends in the circumferential direction around the rotation axis X1 , and is formed in an arc shape when viewed from the direction of the rotation axis X1 .

[0058] The outer diameter R up to the outer periphery of the base portion 60 is set to a larger radius than the radius r up to the outer periphery of the final gear 25 .

[0059] like Figure 2 As shown in (a), in the transmission case 10 , the side surface 25 a of the final gear 25 on the wall portion 13 side is covered by the base portion 60 of the first cover portion 6 .

[0060] like Figure 4 As shown in (a), a plurality of through holes 68 are provided in the base portion 60. Each of the through holes 68 penetrates the base portion 60 in the direction of the rotation axis X1.

[0061] When viewed from the direction of the rotation axis X1 , the through holes 68 are provided at intervals in the circumferential direction around the rotation axis X1 on a virtual circle Im1 centered on the rotation axis X1 .

[0062] The first cover portion 6 of the baffle plate 4 is fixed to the transmission case 10 by bolts (not shown) inserted through the through holes 68 .

[0063] The base portion 60 is further provided with a recessed portion 66 surrounding the through hole 68 and a concave groove 67 .

[0064] The recessed portion 66 is formed in a circular shape surrounding the through hole 68 when viewed from the direction of the rotation axis X1 , and each of the recessed portions 66 is formed to be recessed toward the back side of the paper surface.

[0065] like Figure 4 As shown, when viewed from the direction of the rotation axis X1, the groove 67 is formed to be recessed toward the depth of the paper surface.

[0066] The groove 6 connects recessed portions 66 , 66 adjacent to each other in the circumferential direction around the rotation axis X1 .

[0067] When viewed from the direction of the rotation axis X1, the groove 67 is formed in an arc shape along the virtual circle Im1.

[0068] When viewed from the direction of the rotation axis X1 , the one end 601 of the base portion 60 is formed in an arc shape surrounding the through hole 68 provided on the one end 601 side at a predetermined interval.

[0069] The other end 602 of the base 60 is formed in a straight line along a line segment La extending in the radial direction of the rotation axis X1. Here, the line segment La is a straight line extending in the radial direction of the rotation axis X1 and perpendicular to the rotation axis X1 when viewed from the rotation axis X1 direction.

[0070] An inner wall portion 61 that protrudes toward the front side of the paper is provided at the inner diameter side edge of the base portion 60 .

[0071] The inner wall portion 61 is formed in an arc shape in a plan view, and is provided with a substantially uniform protruding height over the entire length in the circumferential direction around the rotation axis X1.

[0072] An outer wall portion 62 that protrudes toward the front side of the paper is provided at the outer diameter side edge of the base portion 60 .

[0073] The outer wall portion 62 is provided in a range from one end 601 to the other end 602 in the longitudinal direction of the base portion 60 .

[0074] The outer wall portion 62 is formed in an arc shape along the outer circumference of the final gear 25 when viewed from the direction of the rotation axis X1.

[0075] like Figure 1 As shown in (a), in the transmission case 10, the engine oil OL is stored in a region below the vertical line VL direction based on the installation state of the automatic transmission.

[0076] The baffle plate 4 is provided such that one end 62 a and the other end 62 b of an outer wall portion 62 in the circumferential direction around the rotation axis X1 are located above the oil level OL_level of the engine oil OL.

[0077] The outer wall portion 62 is provided with an oil hole 65 at a position below the oil level OL_level of the engine oil OL (see Figure 3 ).

[0078] The oil hole 65 is provided to penetrate the outer wall portion 62 in the thickness direction (radial direction of the rotation axis X1 ).

[0079] like Figure 3 As shown, the outer wall portion 62 is provided to have a predetermined height h1 in the direction of the rotation axis X1.

[0080] The height h1 of the outer wall portion 62 is set to be greater than the thickness W1 of the final gear 25 in the direction of the rotation axis X1 (h1>W1).

[0081] Therefore, if Figure 4 As shown in (b), when viewed from the radial direction of the rotation axis X1, on the lower side of the transmission case 10, the outer periphery of the final gear 25 is covered by an outer wall portion 62 surrounding the final gear 25 at a predetermined interval (eg, 2 mm).

[0082] In the present embodiment, the oil hole 65 is provided at a position substantially in the middle of the outer wall portion 62 in the direction of the rotation axis X1.

[0083] like Figure 4 As shown in (b), a belt-shaped rib 69 is provided on the outer periphery of the outer wall portion 62 .

[0084] The belt-shaped rib body 69 is formed of the same material as that constituting the main body portion 5 (the outer wall portion 62 and the base portion 60 ) and having a large linear expansion coefficient at low temperatures.

[0085] It should be noted that the band-shaped ribs 69 may be formed of a material having a larger linear expansion coefficient at low temperatures than a material constituting the main body 5 (outer wall 62 and base 60 ).

[0086] The belt-shaped ribs 69 are provided in a direction from the vicinity of the oil hole 65 to a direction away from the second cover portion 7 in the circumferential direction around the rotation axis X1 ( Figure 4 (a) in the left direction).

[0087] The region where the belt-shaped ribs 69 are provided is located downstream of the oil hole 65 in the rotation direction of the final gear 25 when the vehicle is traveling forward, and is located on the moving direction side of the engine oil OL stirred up by the rotating final gear 25 .

[0088] The belt-shaped rib 69 is provided at a boundary portion between the outer wall portion 62 and the base portion 60 so as to straddle the outer wall portion 62 and the base portion 60 .

[0089] like Figure 4 As shown in (b), the strip-shaped rib 69 has a deformation promoting portion 691 integrally formed on the outer periphery of the outer wall portion 62 and a bottom portion 692 integrally formed on the back surface of the base portion 60 .

[0090] The deformation promoting portion 691 protrudes outward from the outer periphery of the outer wall portion 62 with a predetermined thickness Wa (eg, 4 mm). The deformation promoting portion 691 is provided within a predetermined angular range from the vicinity of the oil hole 65 to the vicinity of the other end 62b of the outer wall portion 62 in the circumferential direction around the rotation axis X1.

[0091] The height h2 of the deformation promoting portion 691 in the direction of the rotation axis X1 is approximately half of the height h1 of the outer wall portion 62. The deformation promoting portion 691 is provided from the end portion 62c (free end) of the outer wall portion 62 to the side of the base portion 60 ( Figure 4 (b) on the left) of the separation location.

[0092] like Figure 3 As shown, a plurality of recesses 693 (grooves) are provided at intervals in the circumferential direction in the deformation promoting portion 691. The recesses 693 are formed in a rectangular shape when viewed in the radial direction of the rotation axis X1, and the outer periphery of the outer wall portion 62 is exposed in the recesses 693.

[0093] The bottom 692 extends from the outer side of the base 60 to the inner diameter side until the area of ​​the groove 67 (see Figure 4 (b) As described above, the groove 67 is formed by recessing the base 60 , and the area of ​​the groove 67 is flush with the bottom 692 on the outer side of the base 60 .

[0094] like Figure 4 As shown in (a), the base portion 70 of the second cover portion 7 extends from the outer periphery of the outer wall portion 62 of the first cover portion 6 in the radial direction of the rotation axis X1.

[0095] The base portion 70 has a tapered shape in which the width in the circumferential direction around the rotation axis X1 becomes narrower as it moves away from the first cover portion 6 .

[0096] The base 70 of the second cover 7 is disposed at a position offset from the base 60 of the first cover 6 in the direction of the rotation axis X1. Figure 4 In (a), the base 70 of the second cover portion 7 is located closer to the front side of the paper surface than the base 60 of the first cover portion 6 .

[0097] The base 70 has a mounting portion 73 for the cover 9 described later provided at the front end thereof. The mounting portion 73 is provided integrally with the base 70. The mounting portion 73 extends away from the base 70, and a screw hole 73a is opened at the front end thereof.

[0098] An outer wall portion 72 is provided at the boundary between the mounting portion 73 and the base portion 70. Figure 4 In (a), the outer wall portion 72 extends toward the front side of the paper, and the outer wall portion 72 extends along the side edge of the base 70 from the boundary between the mounting portion 73 and the base 70 to the outer wall portion 62 of the first cover portion 6.

[0099] Near the connection between the outer wall portion 72 of the second cover portion 7 and the outer wall portion 62 of the first cover portion 6, a mounting portion 74 of the cover portion 9 described later is provided on the outer periphery of the outer wall portion 62. The mounting portion 74 is provided in the area between the outer wall portion 62 and the outer wall portion 72, and a screw hole 74a opens at the center of the mounting portion 74.

[0100] The mounting portion 74 is provided so that the height position thereof in the direction of the rotation axis X1 coincides with that of the mounting portion 73 described above.

[0101] A plate-like rib 75 is provided near a connection portion between the outer wall portion 72 of the second cover portion 7 and the outer wall portion 62 of the first cover portion 6 .

[0102] The plate-like ribs 75 are provided across the outer wall portion 72 and the outer wall portion 62, and a plurality of plate-like ribs 75 are provided at predetermined intervals in the direction of the rotation axis X1 (see Figure 3 ).

[0103] A plurality of ribs 79 are provided on the outer periphery of the outer wall portion 72 at intervals in the longitudinal direction.

[0104] The ribs 79 are also formed of the same material as that constituting the second cover portion 7 (the outer wall portion 72 and the base portion 70 ) and having a large linear expansion coefficient at low temperatures.

[0105] It should be noted that the rib 79 may be formed of a material having a larger linear expansion coefficient at low temperature than that of a material constituting the second cover portion 7 (the outer wall portion 72 and the base portion 70 ).

[0106] like Figure 4 As shown in (a), the shape of the rib 79 viewed from the rotation axis direction is a semicircular shape with a radius ra, and each rib 79 protrudes outward from the outer periphery of the outer wall portion 72 with its apex P facing outward.

[0107] like Figure 4 As shown in (c), the height h4 of the rib 79 in the direction of the rotation axis X3 is lower than the height h3 of the outer wall 72 in the direction of the rotation axis X1 (h3>h4). In the outer wall 72, the rib 79 is provided at a position close to the base 70, and the rib 79 is provided from the end 72c (free end) of the outer wall 72 to the side of the base 70 ( Figure 4 (c) on the left) of the separation location.

[0108] like Figure 4 As shown in FIG. 2( a ), a through hole 71 is provided in the center of the base 70. The oil pump OP (see FIG. 2 ) Figure 1 ) of the drive shaft SH (refer to Figure 4 (c)) penetrates the through hole 71.

[0109] like Figure 1As shown, in the transmission case 10 , the oil pump OP is arranged on the back side of the second cover portion 7 in the paper, and the driven sprocket DS is arranged on the front side of the second cover portion 7 in the paper.

[0110] In the second cover portion 7 , the driven sprocket DS is coupled to the drive shaft SH in a region between the outer wall portion 72 and the outer wall portion 62 of the first cover portion 6 , so that the driven sprocket DS and the drive shaft SH rotate integrally.

[0111] In the automatic transmission, the rotational driving force input from the engine is transmitted to the driven sprocket DS via the chain CH.

[0112] Thus, the driven sprocket DS and the drive shaft SH rotate about the rotation axis X3, thereby driving the oil pump OP. Figure 1 (a)), the engine oil OL pressurized by the oil pump OP is then supplied to a hydraulic control circuit of the automatic transmission.

[0113] Figure 5 It is a diagram for explaining the cover portion 8 of the baffle 4 . Figure 5 (a) is a diagram showing the cover portion 8 as viewed from the direction of the rotation axis X1. Figure 5 (b) Yes Figure 5 (a) AA cross-sectional view. It should be noted that Figure 5 In (b), a portion of the final gear 25 is indicated by a virtual line.

[0114] like Figure 5 As shown, the cover 8 has a plate-shaped base 80 .

[0115] The base portion 80 extends in a circumferential direction around the rotation axis X1 when viewed from the rotation axis X1 direction, and is formed in an arc shape when viewed from the rotation axis X1 direction.

[0116] like Figure 5 As shown, the outer diameter R1 of the outer periphery of the base 80 is set to be larger than the outer diameter R of the outer wall portion 62 of the main body 5 side (see Figure 4 ) and smaller than the radius r of the outer periphery of the final gear 25 (refer to Figure 4 ) Large radius.

[0117] Therefore, a gap CL1 (see Figure 5 (b)).

[0118] like Figure 5 As shown, in the automatic transmission 1 , the side surface 25 b of the final gear 25 on the torque converter case (not shown) side is covered by the base portion 80 of the cover portion 8 .

[0119] The base portion 80 is provided with a plurality of through holes 85. Each of the through holes 85 penetrates the base portion 80 in the direction of the rotation axis X1.

[0120] When viewed from the direction of the rotation axis X1, each of the through holes 85 is located on a virtual circle Im1 centered on the rotation axis X1. Each of the through holes 85 is provided at intervals in the circumferential direction around the rotation axis X1.

[0121] The cover portion 8 of the baffle plate 4 is fixed to the torque converter case (not shown) by bolts (not shown) inserted through the through holes 85 .

[0122] The base portion 80 is further provided with a recessed portion 86 surrounding the through hole 85 .

[0123] like Figure 5 As shown in (a), when viewed from the direction of the rotation axis X1, each of the recessed portions 86 is formed to be recessed toward the paper surface.

[0124] When viewed from the direction of the rotation axis X1 , one end 801 and the other end 802 of the base portion 80 are formed in a straight line shape along line segments Lb and Lc extending in the radial direction of the rotation axis X1 .

[0125] Here, when viewed from the direction of the rotation axis X1, the line segments Lb and Lc are straight lines that are orthogonal to the rotation axis X1 and extend in the radial direction of the rotation axis X1.

[0126] like Figure 5 As shown, the line segment Lc is located above the line segment La. Therefore, when the cover 8 and the main body 5 are assembled, the other end 802 on the cover 8 side is arranged above the other end 602 on the main body 5 side.

[0127] An inner wall portion 81 that protrudes toward the front side of the paper is provided at the inner diameter side edge of the base portion 80 .

[0128] The inner wall portion 81 is formed into an arc shape when viewed from the direction of the rotation axis X1. The inner wall portion 81 extends over the entire length of the circumference around the rotation axis X1 and is provided with a substantially uniform protruding height h5 (see Figure 5 (b)).

[0129] like Figure 5 As shown in (b), the inner wall portion 81 includes a first tubular portion 811 that is substantially parallel to the rotation axis X1 and a second tubular portion 812 that is inclined in a direction approaching the rotation axis X1 as it moves away from the first tubular portion 811 .

[0130] The inner wall portion 81 surrounds the outer circumference of the differential case 20 at a predetermined interval, and the first tubular portion 811 and the second tubular portion 812 have different inclinations with respect to the rotation axis X1.

[0131] like Figure 5As shown in (b) , in the cover portion 8 , in cross-sectional view, the base portion 80 , the first tubular portion 811 , and the second tubular portion 812 are arranged in this order from the final gear 25 side in the direction of the rotation axis X1 .

[0132] A belt-shaped sealing member 88 is fitted and mounted on the outer peripheral portion 80 a of the base portion 80 .

[0133] The sealing member 88 is a member having a predetermined width W3 and is formed of an elastic material such as a material with a large linear expansion coefficient (e.g., rubber). The sealing member 88 is formed into an arc shape when viewed from the direction of the rotation axis X1 (see Figure 5 (a)).

[0134] The outer diameter R2 of the sealing member 88 is set larger than the outer diameter R of the outer wall portion 62 extending to the main body portion 5 side (see Figure 4 ) with a slightly larger radius.

[0135] like Figure 2 As shown in (a), when the cover 8 is assembled to the main body 5, the outer peripheral edge of the sealing member 88 is pressed against the inner periphery of the outer wall 62, and the gap CL1 between the outer wall 62 on the main body 5 side and the base on the cover 8 side is sealed by the sealing member 88. In this state, a storage chamber Sa (rotating body storage chamber) for the final gear 25 is formed on the outer diameter side of the final gear 25.

[0136] A plurality of ribs 89 are provided on the outer periphery of the first cylindrical portion 811 at intervals in the longitudinal direction.

[0137] The ribs 89 are formed of the same material as that constituting the cover portion 8 (the inner wall portion 81 and the base portion 80 ) and having a large linear expansion coefficient at low temperatures.

[0138] It should be noted that the ribs 89 may be formed of a material having a larger linear expansion coefficient at low temperature than that of a material constituting the lid portion 8 (the inner wall portion 81 and the base portion 80 ).

[0139] like Figure 5 As shown in (a), the shape of the rib 89 viewed from the rotation axis direction is a semicircular shape with a radius rb, and each rib 89 protrudes outward from the outer periphery of the first cylindrical portion 811 with its apex P facing outward.

[0140] The rib 89 is provided across the base 80 and the first cylindrical portion 811. The height h6 of the rib 89 in the direction of the rotation axis X1 is lower than the height h7 of the first cylindrical portion 811 in the direction of the rotation axis X1 (h7>h6). The rib 89 is provided in the first cylindrical portion 811 with a gap on the second cylindrical portion 812 side.

[0141] The contact area between the rib body 89 and the first cylindrical portion 811 is larger than the contact area between the rib body 89 and the base portion 80 .

[0142] The rib 89 is provided from the outer peripheral portion 80a (free end) of the base 80 to the inner wall portion 81 side ( Figure 5 (b) The upper side) of the separation position.

[0143] When the cover 8 is assembled to the main body 5 , the front end side of the sealing member 88 elastically contacts the inner periphery of the outer wall 62 of the main body 5 , and the gap CL1 between the outer wall 62 on the main body 5 side and the outer periphery of the base 80 on the cover 8 side is sealed by the sealing member 88 .

[0144] like Figure 2 As shown in (a), when the cover 8 is assembled to the main body 5, in the area below the final gear 25, the side 25a on one side and the side 25b on the other side in the direction of the rotation axis X1 are respectively covered by the base 60 of the main body 5 and the base 80 of the cover 8, and the outer periphery of the final gear 25 is covered by the outer wall 62 of the main body 5.

[0145] Therefore, the area below the final gear 25 is arranged in a state surrounded by the baffle plate 4 (baffle plate portion) arranged close to the final gear 25 .

[0146] like Figure 5 As shown in (a), in this embodiment, one end 88a of the sealing member 88 in the longitudinal direction is located near the one end 801 (line segment Lb) of the base 80, and the other end 88b extends to the line segment La.

[0147] The sealing member 88 is located on the side where the oil OL stirred up by the final gear 25 moves ( Figure 5 The other end 88b (left side in (a)) is located above the one end 88a.

[0148] Figure 6 It is a diagram for explaining the cover portion 9 of the baffle 4 . Figure 6 (a) is a diagram showing the cover 9 as viewed from the direction of the rotation axis X3. Figure 6 (b) Yes Figure 6 AA section view in (a).

[0149] It should be noted that in Figure 6 In (b), a part of the outer wall portion 72 on the main body 5 side, and a part of the driven sprocket DS and the drive shaft SH are indicated by virtual lines.

[0150] like Figure 6 As shown, the cover 9 has a plate-shaped base 90. When viewed from the direction of the rotation axis X3, the base 90 is oriented from the rotation axis X3 ( Figure 3 The reference) direction may be formed in a shape that coincides with the base 70 of the second cover portion 7.

[0151] When viewed from the rotation axis X1 direction, the base 90 has a first side edge 901 along the outer periphery of the outer wall 62 of the first cover 6 and a second side edge 902 along the inner periphery of the outer wall 72 of the second cover 7 .

[0152] The first side edge 901 and the second side edge 902 are connected to each other at one end in the longitudinal direction. The second side edge 902 is provided at the other end with a mounting portion 91 having a screw hole 91 a.

[0153] The third side edge 903 connected to the other end of the first side edge 901 is on the outer diameter side of the rotation axis X3 of the driven sprocket DS, bypasses the rotation axis X3 and is opposite to the second side edge 902 , and is connected to the mounting portion 91 .

[0154] The base portion 90 is provided with a screw hole 90 c near a connection portion between the first side edge 901 and the second side edge 902 .

[0155] The screw holes 91a and 90c of the cover 9 are arranged at the same positions as the screw holes 73a and 74a of the second cover 7 (see Figure 4 ) corresponding to the position.

[0156] When the base portion 90 is placed on the attachment portions 73 and 74 on the second cover portion 7 side, the second side edge 902 is held with a gap CL2 between the second side edge 902 and the outer wall portion 72 of the second cover portion 7 .

[0157] The cover 9 is held substantially parallel to the base 70 of the second cover 7 by the mounting portions 74 and 73, and is fixed to the second cover 7 by bolts B (see FIG. Figure 3 ).

[0158] A belt-shaped sealing member 98 is fitted and mounted on the outer periphery of the second side edge 902 .

[0159] The sealing member 98 is a member having a predetermined width W4 and is formed of an elastic material such as a material having a large linear expansion coefficient (eg, rubber), and is formed in a curved shape corresponding to the shape of the second side edge 902 .

[0160] like Figure 2 As shown in (b), when the cover part 9 is assembled on the second cover part 7 on the side of the main body part 5, the outer peripheral edge of the sealing component 98 is pressed against the inner periphery of the outer wall part 72 of the second cover part 7, and the sealing component 98 seals the gap CL2 between the outer wall part 72 on the side of the main body part 5 and the base 90 on the cover part 9 side.

[0161] In this state, a housing chamber Sb (rotating body housing chamber) for the driven sprocket DS is formed on the outer diameter side of the driven sprocket DS.

[0162] like Figure 2As shown in (b), when the cover portion 9 is assembled to the second cover portion 7, in the area on the lower side of the driven sprocket DS, the side surface DSa on one side and the side surface DSb on the other side in the direction of the rotation axis X3 are respectively covered by the base 70 of the second cover portion 7 and the base 90 of the cover portion 9, and the outer periphery of the driven sprocket DS is covered by the outer wall portion 72 of the second cover portion 7.

[0163] The area below the driven sprocket DS is arranged in a state surrounded by the second cover portion 7 and the cover portion 9 of the retaining plate 4 .

[0164] As described above, the main body 5 of the baffle plate 4 is provided with the oil holes 65 (see Figure 3 ).

[0165] The oil hole 65 is provided in the outer wall portion 62 at a position below the oil surface OL_level of the engine oil OL in the vertical direction based on the installation state of the automatic transmission 1 .

[0166] In this embodiment, the negative pressure generated when the final gear 25 rotates allows the oil OL between the outer periphery of the outer wall portion 62 and the inner periphery of the peripheral wall portion 11 of the transmission case 10 to flow into the final gear 25 through the oil hole 65 .

[0167] That is, the engine oil OL on the outside of the outer wall portion 62 can flow into the inside of the outer wall portion 62 .

[0168] Here, when the amount of the engine oil OL flowing into the inner side of the outer wall portion 62 increases, the inflowing engine oil OL becomes friction with respect to the rotation of the final gear 25 .

[0169] If the amount of oil OL flowing into the inner side of the outer wall portion 62 is too small, lubrication of not only the final gear 25 but also the area around the reduction gear 35 is insufficient. This is because the amount of oil lifted up by the final gear 25 and supplied to the reduction gear 35 is reduced.

[0170] The baffle plate 4 is provided for the following purpose.

[0171] (a) The engine oil OL stirred up by the final gear 25 is guided to the reduction gear 35 (other gears).

[0172] (b) The resistance (stirring resistance) when the final gear 25 rotates is reduced.

[0173] Therefore, the opening diameter of the oil hole 65 is set to the minimum diameter that can achieve the above-mentioned purposes (a) and (b) based on experimental results and simulations.

[0174] In the automatic transmission, when the oil pump OP is driven, the oil is pumped through an oil filter 17 (see FIG. Figure 1(a)), the oil in the oil pan 16 is sucked by the oil pump OP.

[0175] Then, the engine oil OL whose pressure is regulated by the oil pump OP is used for operation of the speed change mechanism portion and lubrication of the main rotating parts, and then returns to the oil pan 16 by its own weight.

[0176] An amount of oil required for lubricating the operation of the transmission mechanism and the main rotating parts is stored in an oil pan 16 fixed to the lower portion of the transmission 10 .

[0177] Here, after the engine is started in a low temperature environment such as winter, the temperature of the engine oil in the automatic transmission 1 is low, so the fluidity of the engine oil OL decreases.

[0178] In such a case, since the return flow of the engine oil OL to the oil pan 16 is deteriorated, when the engine oil OL in the oil pan 16 is insufficient, air may be sucked from the suction port of the oil filter 17 .

[0179] In this way, when the oil containing air is used in the operation of the speed change mechanism, shock and the like may be generated.

[0180] In this embodiment, in order to facilitate the return of the oil in the baffle plate 4 to the oil pan 16 when the temperature of the oil OL is low, the baffle plate 4 is provided with the belt-shaped ribs 69 and 79 and the cover 8 is provided with the ribs 89 .

[0181] The belt-shaped ribs 69 and the ribs 79 and 89 are formed of the same material as the material of the main structural members constituting the baffle 4 and having a large linear expansion coefficient at low temperatures.

[0182] Therefore, in the present embodiment, a part of the belt-shaped rib 69 and the ribs 79 and 89 contracts more than other parts at low temperatures, so that other parts adjacent to the belt-shaped rib 69 and the ribs 79 and 89 are greatly deformed.

[0183] The following is a detailed description.

[0184] Figure 7 It is a diagram for explaining the function of the baffle plate 4 and is a diagram for explaining the function of the belt-shaped rib 69 and the ribs 79 and 89 .

[0185] Figure 7 (a) is a diagram for explaining deformation of the outer wall portion 62 and the base portion 80 caused by the belt-shaped ribs 69 and the ribs 89 . Figure 7 (b) is a diagram for explaining deformation of the outer wall portion 72 caused by the ribs 79 .

[0186] like Figure 7As shown in (a), at low temperatures, the ribs 89 on the cover 8 side shrink more than other regions (base 80, inner wall 81) adjacent to the ribs 89 (see arrows in the figure).

[0187] Here, in the region adjacent to the rib 89 (base 80 , inner wall 81 ), the inner wall 81 is formed in a shape that is bent at the boundary between the first tubular portion 811 and the second tubular portion 812 , and is therefore less likely to bend than the base 80 .

[0188] On the other hand, the rigidity and strength of the inner wall portion 81 side (inner diameter side: rotation axis X1 side) of the base portion 80 are increased, and the outer diameter side (outer peripheral portion 80a: free end) side is displaceable in the rotation axis X1 direction.

[0189] Therefore, as the rib body 89 contracts, the base 80 is pulled toward the rib body 89 side, and the outer peripheral portion 80 a side of the base 80 is bent in a direction away from the final gear 25 .

[0190] Furthermore, at low temperatures, the strip-shaped ribs 69 on the first cover portion 6 side shrink more than other regions (the base portion 60 and the outer wall portion 62 ) adjacent to the strip-shaped ribs 69 (see arrows in the figure).

[0191] Here, in the area adjacent to the strip-shaped rib 69 (base 60, outer wall 62), the base 60 is provided with a step caused by the groove 67, and this portion also serves as a reinforcing rib, so it is more difficult to bend than the outer wall 62.

[0192] On the other hand, the base 60 side of the outer wall portion 62 has higher strength than the end portion 62 c on the cover portion 8 side, and the end portion 62 c (free end) side of the outer wall portion 62 is displaceable in the radial direction of the rotation axis X1.

[0193] Therefore, in the baffle 4, when the strip-shaped ribs 69 and the ribs 89 contract at low temperatures, the end 62c side of the outer wall portion 62 and the outer peripheral portion 80a side of the base portion 80 are displaced in a direction away from each other, and the sealing member 88 provided at the outer peripheral portion 80a is displaced in a direction away from the outer wall portion 62 (see Figure 7 (a)).

[0194] thus,

[0195] (I) The seal of the gap between the inner periphery of the outer wall portion 62 of the body portion 5 and the base portion 80 of the cover portion 8 by the seal member 88 is released when the temperature of the engine oil OL is low, thereby generating the gap CL′.

[0196] Since the outer wall portion 62 is located downward in the vertical direction based on the installation state of the automatic transmission, the low-fluidity engine oil OL accumulated inside the outer wall portion 62 is discharged downward toward the oil pan 16 .

[0197] Here, in this embodiment, the belt-shaped rib body 69 is provided from the outer wall portion 62 to the base portion 60. Therefore, when the belt-shaped rib body 69 contracts, the belt-shaped rib body 69 contracts and is pulled toward the base portion 60 side ( Figure 7 (a) on the left side). Therefore, by increasing the displacement amount on the end portion 62c side of the outer wall portion 62, the gap CL' between the outer peripheral portion 80a of the base portion 80 on the cover portion 8 can be further enlarged.

[0198] Furthermore, a plurality of recessed portions 693 (groove portions) are provided at intervals in the circumferential direction around the rotation axis X1 in the deformation promoting portion 691 of the belt-shaped rib body 69 .

[0199] Therefore, the displacement amount of the region where the recessed portion 693 is provided in the circumferential direction around the rotation axis X1 is smaller than that of the region where the deformation promoting portion 691 is provided.

[0200] In this way, the end portion 62c side of the outer wall portion 62 formed in an arc shape can be deformed into a wave shape when viewed from the direction of the rotation axis X1.

[0201] This can partially expand the gap CL′ between the outer peripheral portion 80 a of the base portion 80 on the cover portion 8 side, so that the low-fluidity engine oil OL accumulated inside the outer wall portion 62 can be more appropriately discharged downward toward the oil pan 16 side.

[0202] In addition, if Figure 7 As shown in (b), the outer wall portion 72 of the second cover portion 7 is provided with ribs 79 on the outer periphery of the base portion 70 side.

[0203] Therefore, the strength of the outer wall 72 on the base 70 side is higher than that of the end 72 c on the cover 9 side, and the outer wall 72 is easily displaced in the region (base 70 and outer wall 72 ) adjacent to the rib 79 in the second cover 7 .

[0204] Therefore, in the baffle 4, when the ribs 79 shrink at low temperatures, the end 72c (free end) side of the outer wall portion 72 is displaced in the radial direction of the rotation axis X3 in a direction away from the base 90, and the sealing member 98 provided on the outer peripheral portion 90a of the base 90 is separated from the outer wall portion 72 (see Figure 7 (b)).

[0205] thus,

[0206] (II) When the temperature of the engine oil OL is low, the gap between the inner periphery of the outer wall portion 72 of the body portion 5 and the base portion 90 of the cover portion 9 sealed by the sealing member 98 is released, thereby generating the gap CL′.

[0207] Since the outer wall portion 72 is located downward in the vertical direction based on the installation state of the automatic transmission, the low-fluidity engine oil OL accumulated inside the outer wall portion 72 is discharged downward toward the oil pan 16 .

[0208] Thus, in this embodiment, in order to facilitate the return of the oil in the baffle plate 4 to the oil pan 16 when the temperature of the oil OL is low, the belt-shaped ribs 69 and 79 are provided on the body 5 side, and the ribs 89 are provided on the cover 8 side.

[0209] The above-mentioned belt-shaped ribs 69 and ribs 79 and 89 are formed of a material having a large linear expansion coefficient at low temperatures (a material that shrinks at low temperatures). At low temperatures, parts of the belt-shaped ribs 69 and ribs 79 and 89 shrink more than other parts.

[0210] As a result, the sealing of gap CL1 (gap between outer wall portion 62 and base portion 80) by sealing member 88 and the sealing of gap CL2 (gap between outer wall portion 72 and base portion 90) by sealing member 98 are released, thereby forming a gap CL′ through which oil OL can be discharged.

[0211] There are materials that expand at low temperatures and materials that contract at low temperatures.

[0212] First, by selecting a material that shrinks at low temperatures, movement of the main components of the baffle portion (outer wall portions 62 and 72 of the main body 5 and base portion 80 of the cover 8) is promoted when the oil temperature is low, thereby releasing the seal provided by the sealing members 88 and 98.

[0213] Here, simply replacing the main components (belt-shaped ribs 69, ribs 79, 89) of the baffle 4 (baffle portion) with a material that shrinks at low temperatures may fail to release the seal performed by the sealing member.

[0214] This is because, for example, if the amount of shrinkage is small at low temperatures and the sealing members 88 and 98 are not shrunk to such an extent that they are separated from the outer wall portions 62 and 72 of the baffle plate 4 , the seal cannot be released.

[0215] Therefore, in the present embodiment, the dimensions (widths W3 and W4 ) of the sealing members 88 and 98 and / or the dimensions of each portion of the baffle plate 4 are set in consideration of the contraction length.

[0216] For example, the shrinkage amount when the temperature is lowered from the reference temperature to the predetermined temperature is considered, and the following dimensions are set for the dimensions that separate the sealing members 88 and 98 from the outer wall portions 62 and 72 of the baffle 4 when the shrinkage amount occurs.

[0217] That is, the dimensions (widths W3, W4) of the sealing members 88, 98 and / or the dimensions on the baffle plate 4 side (heights h1, h3 of the outer wall portions 62, 72, width W1 of the base portion 80 of the cover portion 8, gap CL1 between the outer peripheral portion 80a of the base portion 80 of the cover portion 8 and the outer wall portion 62 (see Figure 5 (b)) a gap CL2 between the outer peripheral portion 90a of the base 90 of the cover 9 and the outer wall portion 72 (see Figure 6 (b))).

[0218] Here, the reference temperature may be set to any temperature higher than the specified temperature, for example, it may be set to room temperature (25°C), or it may be set to any temperature according to the use range of the normal use temperature (tens to hundreds of degrees Celsius).

[0219] That is, for example, the smaller the pressing force of the sealing members 88 and 98 on the baffles (outer wall portions 62 and 72) at the reference temperature, the smaller the amount of contraction required when the temperature is lowered from the reference temperature to a temperature lower than a predetermined temperature.

[0220] Since the pressing force of the sealing members 88 and 98 on the baffle 4 (outer wall portions 62 and 72) depends on the dimensions of the sealing members 88 and 98 and / or the baffle 4, the dimensions may be set so that the pressing force on the baffle 4 is small at room temperature.

[0221] Furthermore, by setting the above-mentioned dimensions, a gap is formed at a low temperature, and the return of oil from the inside of the baffle plate 4 (baffle plate portion) to the oil pan 16 side can be promoted.

[0222] It should be noted that the dimensions can be appropriately set by a person skilled in the art by conducting experiments and / or calculations in advance in combination with the properties (linear expansion coefficient, etc.) of the material used.

[0223] For example, the size can be predetermined by various methods as follows.

[0224] The temperature of the baffle plate 4 (baffle plate portion) is changed to measure the change in dimension.

[0225] A sample was prepared using the material used for the baffle plate 4 (baffle plate portion), and the temperature was changed to measure the change in dimension.

[0226] The theoretical shrinkage amount is calculated from the linear expansion coefficient of the material used for the baffle 4 (baffle portion) and the design dimensions of the baffle portion.

[0227] In the present embodiment, as the material constituting the belt-shaped ribs 69 and the ribs 79 and 89 , a polymer material is used as an example.

[0228] Since the linear expansion coefficient of the material is not limited, any material such as metal (including pure metal and alloy), ceramic, polymer (especially organic polymer (polymer formed from organic compound) etc.) can be used.

[0229] However, when a material with a small linear expansion coefficient (such as metal) is used, the pressing force of the sealing members 88 and 98 on the baffle plate at the reference temperature needs to be set to be very small, and the sealing performance of the sealing members 88 and 98 will be reduced.

[0230] In addition, the linear expansion coefficient is preferably within the following range.

[0231] In the case of metal, the linear expansion coefficient is 5 to 25x10 -6 K -1 In the case of ceramics, the linear expansion coefficient is 0.5 to 15x10 -6 K -1 In the case of polymers, the linear expansion coefficient is 50 to 300 x 10 -6 K -1 .

[0232] As described above, in this embodiment, the main components of the baffle portion (baffle 4), namely, the main body 5, the lids 8, 9, and the sealing members 88, 98 are all formed of a material such as a polymer having a large linear expansion coefficient at low temperatures.

[0233] The present invention is not limited to this embodiment, as long as at least one of the main body 5, the cover 8, 9, and the sealing member 88, 98 is formed of a material such as a polymer having a large linear expansion coefficient at low temperatures. In this case, a combination of main structural components formed of materials such as polymers can be appropriately selected.

[0234] Furthermore, when the main body 5 and the lids 8 and 9 are formed of a polymer or the like, the main body 5 and the lids 8 and 9 do not necessarily all need to be formed of a polymer or the like, and only a part of the above-mentioned area may be formed of a polymer or the like.

[0235] Likewise, when the sealing members 88 and 98 are formed of a material such as a polymer, the entire sealing members 88 and 98 need not be formed of a material such as a polymer, and only a part of the above-mentioned region may be formed of a material such as a polymer.

[0236] As described above, this embodiment has the following structure.

[0237] (1) The power transmission device (automatic transmission 1) has:

[0238] A pair of baffles (main body 5, cover 8, 9);

[0239] a baffle portion (baffle 4) including sealing members 88, 98 provided in a region between a pair of baffles;

[0240] Rotating parts (final gear 25, driven sprocket DS), which are arranged inside the rotating parts chamber (storage chamber Sa, Sb) which is a space surrounded by the baffle portion;

[0241] an oil pump OP serving as a supply source of lubricating oil (engine oil OL) to the rotating components (the final gear 25 and the driven sprocket DS);

[0242] The oil pan 16 stores oil (engine oil OL) serving as a suction source of the oil pump OP.

[0243] One of the pair of baffles (main body 5, cover 8, 9), the other of the pair of baffles (main body 5, cover 8, 9), or at least any one of the sealing components 88, 98 is composed of a material that contracts as the oil temperature (temperature of the engine oil OL) decreases (a material having a large linear expansion coefficient at low temperatures).

[0244] The baffle portion (main body 5, cover 8, 9) is set to the following dimensions, that is, when the oil temperature is above the specified oil temperature, the area (gaps CL1, CL2) between the pair of baffles (main body 5, cover 8, 9) is sealed by the sealing components 88, 98, and when the oil temperature is lower than the specified oil temperature, a gap CL' is formed in the area between the pair of baffles (main body 5, cover 8).

[0245] The gap CL1 is a gap between the inner periphery of the outer wall portion 62 of the main body portion 5 and the outer peripheral portion 80 a of the base portion 80 of the cover portion 8 .

[0246] The gap CL2 is a gap between the inner periphery of the outer wall portion 72 of the main body 5 and the outer peripheral portion 90 a of the base portion 90 of the cover portion 9 .

[0247] With this structure, the sealing of the gaps CL1, CL2 between the inner periphery of the outer wall portion 62, 72 of the main body 5 and the outer periphery 80a, 90a of the base portion 80, 90 of the cover portion 8, 9 by the sealing members 88, 98 is released when the temperature of the engine oil OL is low, thereby generating gaps CL', CL'.

[0248] Since the outer wall portions 62 , 72 are located downward in the vertical direction based on the installation state of the automatic transmission 1 , the low-fluidity engine oil OL accumulated inside the outer wall portions 62 , 72 is discharged downward toward the oil pan 16 .

[0249] Thus, the gap CL′ is formed at low temperature, and the oil return (the return flow of the engine oil OL) from the inside of the baffle portion (the body portion 5 , the cover portions 8 , 9 ) to the oil pan 16 side can be promoted.

[0250] Furthermore, by providing the sealing members 88 and 98 , the clearance CL′ can be made 0 (zero) by the sealing members 88 and 98 before the temperature drops below a predetermined level, thereby improving the effect of suppressing the intrusion of oil when the oil temperature rises.

[0251] This embodiment has the following structure.

[0252] (2) The material is a polymer material, and the polymer material is a resin material or a rubber material.

[0253] By using a polymer having a high linear expansion coefficient, the amount of shrinkage can be increased, the pressing force of the sealing members 88 and 98 on the baffle (outer wall portions 62 and 72) at the reference temperature can be increased, and the sealing performance of the sealing members 88 and 98 can be improved.

[0254] This embodiment has the following structure.

[0255] (3) The baffle portion (main body 5, cover 8) has ribs (belt-shaped ribs 69, ribs 79, 89) made of a polymer material.

[0256] When ribs (strip ribs 69, ribs 79, 89) made of polymer material are formed on the baffle part (main body 5, cover part 8) or the polymer material part of the sealing part, the thicker the polymer material is, the greater the shrinkage / expansion caused by temperature changes, so the gap CL' formed at low temperature can be further expanded.

[0257] Therefore, by providing ribs (belt-shaped ribs 69, ribs 79, 89) to form a locally thick portion, it is possible to increase the amount of contraction / expansion due to temperature changes.

[0258] Thus, even if the pressing force of the sealing members 88 and 98 on the outer wall portions 62 and 72 is increased at the reference temperature, the sealing members 88 and 98 can be separated from the outer wall portions 62 and 72 at low temperatures to form the gap CL'. Therefore, the sealing performance of the storage chambers Sa and Sb of the baffle plate 4 can be improved.

[0259] Here, although it is conceivable to increase the thickness of the entire baffle plate 4, it is not necessary to do so, and by forming a rib body with a partially increased thickness, effects such as weight reduction and cost reduction can be obtained.

[0260] In addition, for example, since the baffle portion (main body 5, lid 8, 9) or sealing components 88, 98 made of polymer material are formed by cooling the raw material after melting, the surface area of ​​the thicker portion can be increased, and the cooling efficiency can be relatively improved.

[0261] Although deformation, cracks, and the like may occur when the cooling efficiency is deteriorated, the effect of appropriately preventing such occurrences can be obtained by improving the cooling efficiency.

[0262] This embodiment has the following structure.

[0263] (4) The automatic transmission 1 (power transmission device) has:

[0264] A baffle portion (baffle 4), which includes a pair of baffles (main body 5, cover 8, 9);

[0265] Rotating parts (final gear 25, driven sprocket DS) are arranged inside the rotating parts chamber (storage chamber Sa, Sb) which is a space surrounded by the baffle portion (baffle 4);

[0266] an oil pump OP serving as a supply source of lubricating oil (engine oil OL) to the rotating components (the final gear 25 and the driven sprocket DS);

[0267] The oil pan 16 stores oil (engine oil OL) serving as a suction source of the oil pump OP.

[0268] At least one of the pair of baffles (body 5, lids 8, 9) contains a polymer material.

[0269] The baffle portion (baffle 4 ) has ribs (belt-shaped ribs 69 , ribs 79 , 89 ) made of a polymer material.

[0270] The thicker the polymer material is, the greater the amount of shrinkage / expansion due to temperature changes. Therefore, by providing ribs (belt-shaped ribs 69, ribs 79) to make the locally thicker portion, the amount of shrinkage / expansion due to temperature changes can be increased.

[0271] Therefore, in the case of a baffle without a sealing member, since the change in the gap accompanying the temperature change can be increased, the gap at the reference temperature can be set smaller, and the effect of reducing the stirring resistance can be enhanced.

[0272] On the other hand, in the case of a baffle having a sealing member, the change in the gap accompanying the temperature change can be increased, thereby increasing the pressing force of the sealing member at the reference temperature, thereby improving the sealing performance and the effect of reducing the stirring resistance.

[0273] This embodiment has the following structure.

[0274] (5) A plurality of ribs 79, 89 are provided.

[0275] When the ribs have the same volume, a plurality of ribs can increase the surface area more than a single rib, so the cooling efficiency can be improved.

[0276] This embodiment has the following structure.

[0277] (6) The belt-shaped rib body 69 is provided with a groove portion (recessed portion 693 ).

[0278] Providing the groove (recess 693) can increase the surface area, thereby improving the cooling efficiency of a portion of the belt-shaped rib 69. It should be noted that grooves may be provided in other ribs 79 and 89 to increase the surface area.

[0279] This embodiment has the following structure.

[0280] (7) The ribs (belt-shaped ribs 69 and ribs 89) are arranged at positions separated from the gap CL1 where the gap CL' is generated.

[0281] The rib 79 is disposed at a position separated from the gap (gap CL2).

[0282] The belt-shaped rib 69 is disposed at a position separated from the gap CL1 in the direction of the rotation axis X1.

[0283] The rib body 89 is arranged at a position separated from the gap CL1 in the radial direction of the rotation axis X1.

[0284] The gap CL1 is a gap between the outer wall portion 62 where the belt-shaped ribs 69 are provided and the base portion 80 on the cover portion 8 side where the ribs 89 are provided.

[0285] The gap CL1 is a gap in the radial direction of the rotation axis X1 between the end portion 62 c of the outer wall portion 62 and the outer peripheral portion 80 a of the base portion 80 .

[0286] The gap CL2 is a gap between the outer wall portion 72 provided with the rib 79 and the base portion 90 on the cover portion 9 side.

[0287] The gap CL2 is a gap in the radial direction of the rotation axis X1 between the end portion 72 c of the outer wall portion 72 and the outer peripheral portion 90 a of the base portion 90 .

[0288] By placing the ribs (belt-shaped ribs 69 , ribs 79 , 89 ) at positions separated from the gap CL1 where the gap CL′ is generated, it is possible to increase the change in the gap CL′ accompanying contraction / expansion.

[0289] That is, when the amount of contraction / expansion is constant, the greater the distance from the gaps CL1 and CL2 , the greater the change in the gap CL′ due to contraction / expansion, and the greater the amount of contraction / expansion, the greater the change in the gap CL′.

[0290] Therefore, the farther the ribs (belt-shaped ribs 69, ribs 79, 89) with large shrinkage / expansion amounts are from the gaps CL1 and CL2 where the gaps CL' are generated, the greater the amount of change in the generated gap CL'.

[0291] This embodiment has the following structure.

[0292] (8) At least one of the pair of baffles has a plate portion (cover portion 8) adjacent to the gap CL1 where the gap is generated,

[0293] Assuming that the plate portion (cover portion 8) is divided into two regions (base portion 80 and inner wall portion 81) in the axial direction (rotation axis X1) of the rotating member (final gear 25),

[0294] The rib 89 is arranged so that the area overlapping with the region not adjacent to the gap (inner wall 81 ) is larger than the area overlapping with the region adjacent to the gap (gap CL1 ) (base 80 ) of the two regions (base 80 , inner wall 81 ).

[0295] The region (inner wall portion 81 ) not adjacent to the gap extends in the direction of the rotation axis X1 from a position separated from the gap (gap CL1 ) in the region (base portion 80 ) adjacent to the gap (gap CL1 ).

[0296] By arranging the rib 89 on the deep side when viewed from the gap (gap CL1 ), the rib 89 can be provided at a position away from the gap CL1 where the gap occurs, so the amount of change in the gap can be further increased.

[0297] This embodiment has the following structure.

[0298] (9) At least one of the pair of baffles, i.e., the main body 5, has: a first plate portion (base portion 60) adjacent to the gap CL1 where the gap is generated, and a second plate portion (outer wall portion 62) adjacent to the first plate portion and protruding toward the axial direction (rotation axis X1 direction) of the rotating body (final gear 25).

[0299] The rib body (belt-shaped rib body 69 ) is provided on the second plate portion (outer wall portion 62 ) side.

[0300] Since the rib body (belt-shaped rib body 69 ) can be provided at a position separated from the gap CL1 where the gap is generated, the amount of change in the gap can be further increased.

[0301] (10) The rib body (belt-shaped rib body 69) is arranged so as to be in contact with the boundary between the first plate portion (base portion 60) and the second plate portion (outer wall portion 62).

[0302] The rib body (belt-shaped rib body 69 ) is provided across the first plate portion (base portion 60 ) and the second plate portion (outer wall portion 62 ), and is arranged in contact with the first plate portion (base portion 60 ) and the second plate portion (outer wall portion 62 ).

[0303] Since the rib body (belt-shaped rib body 69 ) can be provided at a position separated from the gap CL1 where the gap is generated, the amount of change in the gap can be further increased.

[0304] In addition, since the force can be directly applied to the first plate portion (base portion 60), the amount of change in the gap can be further increased.

[0305] This embodiment has the following structure.

[0306] (11) The ribs (belt-shaped ribs 69 and ribs 89) are provided on both sides of the pair of baffles (main body 5 and cover 8).

[0307] Since the contraction force of the ribs (ribs 69 and 89) can act on both the main body 5 and the cover 8, a force for opening the gap (gap CL1) can be applied to both the outer wall 62 on the main body 5 and the base 80 on the cover 8. Therefore, the amount of change in the gap can be further increased.

[0308] This embodiment has the following structure.

[0309] (12) The ribs (belt-shaped ribs 69 and ribs 89) are arranged outside the rotating member chamber (accommodation chamber Sa) of the rotating member (final gear 25).

[0310] When ribs (belt ribs 69, ribs 89) are arranged on the inner side of the rotating component chamber (storage chamber Sa), interference with the rotating component (final gear 25) may occur, which will increase the design restrictions of the rotating component (final gear 25), so the ribs are arranged on the outside.

[0311] This embodiment has the following structure.

[0312] (13) The rotating member is a gear (final gear 25) or a sprocket (driven sprocket DS).

[0313] The final gear 25 and the driven sprocket DS are arranged at the lower part in the transmission case, and the baffle (the main body 5 and the cover 8 ) is provided in a range spanning the final gear 25 and the driven sprocket DS.

[0314] Therefore, by providing the ribs, the sealing of the gap CL1 by the sealing member is released, and the engine oil OL retained in the baffle at an extremely low temperature can be returned to the oil pan 16 side at the lower part of the transmission 10 .

[0315] Since the seal performed by the sealing member 88 can be released only at extremely low temperatures, fuel economy is affected.

[0316] In the above-described embodiment, the driving force transmission device is exemplified as a vehicle automatic transmission. However, the driving force transmission device of the present invention is not limited to a vehicle automatic transmission.

[0317] It can also be applied to a device composed of a gear train composed of a plurality of gears, and at least one gear can stir up the oil in the storage box of the gear train. As the above device, a speed reduction device that reduces the input rotation speed and outputs it is exemplified.

[0318] Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above and can be modified appropriately within the scope of the technical concept of the invention.

Claims

1. A power transmission device, comprising: The baffle portion comprises: a pair of baffles, and a sealing member disposed in a region between the pair of baffles; a rotating member disposed in a rotating member chamber, which is a space surrounded by the baffle portion; an oil pump serving as a supply source of lubricating oil supplied to the rotating component; an oil pan storing oil serving as a suction source for the oil pump; The power transmission device is characterized in that One of the pair of baffles, the other of the pair of baffles, or at least one of the sealing member is formed of a material that shrinks as the oil temperature decreases. The material is formed of a polymer material, The baffle portion has a plurality of ribs which are partially thick and are formed by the material formed by the polymer material. The baffle portion is set to have the following dimensions, namely, when the oil temperature is above a specified temperature, the outer peripheral edge of the sealing component is pressed against the outer wall portion of the baffle portion covering the outer periphery of the rotating component due to the expansion of the rib body, and when the oil temperature is lower than the specified temperature, a gap is formed in the area between the pair of baffles due to the contraction of the rib body.

2. A power transmission device, comprising: The baffle portion comprises: a pair of baffles, and a sealing member disposed in a region between the pair of baffles; a rotating member disposed in a rotating member chamber, which is a space surrounded by the baffle portion; an oil pump serving as a supply source of lubricating oil supplied to the rotating component; an oil pan storing oil serving as a suction source for the oil pump; The power transmission device is characterized in that One of the pair of baffles, the other of the pair of baffles, or at least one of the sealing member is formed of a material that shrinks as the oil temperature decreases. The baffle portion is set to have a size such that, when the oil temperature is above a predetermined temperature, the outer peripheral edge of the sealing member is pressed against the outer wall portion of the baffle portion covering the outer periphery of the rotating member, and when the oil temperature is below the predetermined temperature, a gap is formed in the region between the pair of baffles. The material is formed of a polymer material, The baffle portion has a rib body formed by the material formed of the polymer material, At least one of the pair of baffles has a plate portion adjacent to the gap, Assuming that the plate portion is divided into two regions in the axial direction of the rotating member, the rib body is arranged so that the area overlapping with the region of the two regions not adjacent to the gap is larger than the area overlapping with the region of the two regions adjacent to the gap.

3. A power transmission device, comprising: The baffle portion comprises: a pair of baffles, and a sealing member disposed in a region between the pair of baffles; a rotating member disposed in a rotating member chamber, which is a space surrounded by the baffle portion; an oil pump serving as a supply source of lubricating oil supplied to the rotating component; an oil pan storing oil serving as a suction source for the oil pump; The power transmission device is characterized in that One of the pair of baffles, the other of the pair of baffles, or at least one of the sealing member is formed of a material that shrinks as the oil temperature decreases. The baffle portion is set to have a size such that, when the oil temperature is above a predetermined temperature, the outer peripheral edge of the sealing member is pressed against the outer wall portion of the baffle portion covering the outer periphery of the rotating member, and when the oil temperature is below the predetermined temperature, a gap is formed in the region between the pair of baffles. The material is formed of a polymer material, The baffle portion has a rib body formed by the material formed of the polymer material, At least one of the pair of baffles includes a first plate portion adjacent to the gap and a second plate portion adjacent to the first plate portion and protruding toward the axial direction of the rotating body. The rib body is disposed on the second plate portion.

4. The power transmission device according to any one of claims 1 to 3, characterized in that: The polymer material is formed of a resin material or a rubber material.

5. The power transmission device according to any one of claims 1 to 3, characterized in that: The rib is disposed at a position separated from the gap.

6. The power transmission device according to claim 3, characterized in that: The rib body is disposed in contact with a boundary between the first plate portion and the second plate portion, and is disposed in contact with both the first plate portion and the second plate portion.

7. A power transmission device, comprising: a baffle portion including a pair of baffles; a sprocket disposed in a space surrounded by the baffle portion, that is, inside the rotating component chamber; an oil pump serving as a supply source of lubricating oil supplied to the sprocket; an oil pan storing oil serving as a suction source for the oil pump; The power transmission device is characterized in that At least one of the pair of baffles is made of a polymer material. The baffle portion has a rib body formed by a material formed of the polymer material, The rib body includes a deformation promoting portion formed integrally with the outer circumference of the outer wall portion, and a plurality of grooves are provided at intervals in the circumferential direction on the deformation promoting portion.

8. The power transmission device according to any one of claims 1 to 3 and 7, characterized in that: The ribs are disposed on both sides of the pair of baffles.

9. The power transmission device according to any one of claims 1 to 3 and 7, characterized in that: The rib body is arranged outside the rotating component chamber.

Images