power transmission device

Abstract

To provide a power transmission device capable of more effectively capturing foreign matters mixed in lubricating liquid in a case.SOLUTION: A power transmission device includes: a case; a gear installed in the case; and a baffle plate provided between a side surface of the gear and a side wall of the case in the case. Inside of the case includes: a narrow part including a lubricating liquid and having a clearance with a predetermined dimension or less in a gap between the side wall of the case and the baffle plate; and a lubricating liquid flow passage that is provided in at least a portion excluding the narrow part in the gap and in which the lubricating liquid flows. Due to this configuration, when the lubricating liquid passes through the narrow part in the gap between the side wall of the case and the baffle plate, foreign matters with a size equal to or larger than a predetermined size mixed into the lubricating liquid can be captured.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a power transmission device, and more particularly to a power transmission device having a foreign matter removal structure for removing foreign matter contained in lubricating fluid within the case of a belt-type continuously variable transmission (CVT). [Background technology]

[0002] In a conventional belt-type continuously variable transmission (CVT), a type of power transmission device, the lubricating and cooling oil (such as automatic transmission fluid (ATF) or constant voltage fluid (CVTF), hereafter referred to as "lubricant") circulating within the case has two routes: one in which the lubricant stored in a control chamber (oil pan) located at the bottom of the case is pumped up by an oil pump and supplied to various parts within the case, and the other in which the lubricant stored in a lubricant reservoir (separate from the control chamber) located at the bottom of the case, where the final gear (the lowest gear in the case) is partially submerged, is scooped up by the rotation of the final gear and splashed into the case, thereby supplying various parts within the case. The lubricant supplied to the upper part of the case via these routes falls down, lubricating and cooling each part of the belt-type continuously variable transmission within the case, before being collected again in the control chamber and lubricant reservoir.

[0003] The case (transmission case) housing a belt-type continuously variable transmission should be kept clean during operation. If foreign matter enters the lubrication system inside the case, for example, if the foreign matter is iron powder in size, the impact will be minimal if the amount is small. However, if the amount is large, it may affect wear on the drivetrain. If the foreign matter is the size of chips or sand, it will wear out faster than iron powder. If the foreign matter exceeds a certain size, it may cause problems, such as damage to the drivetrain (gear meshing, etc.) or a significantly shorter lifespan than normal, regardless of the amount or speed. In the case of a belt-type continuously variable transmission, foreign matter of this size is rarely present inside the case. However, if foreign matter enters from the outside through the oil filler port or is generated for some other reason, the size of the foreign matter that may have a greater impact on the drivetrain will depend on the size of the rigid components that make up the endless belt that transmits power between the pulleys, as well as the size of the transmission's construction.

[0004] As described above, the lubricating fluid in the case flows through two routes: one supplied from the control chamber and the other from the lubricating fluid reservoir. The control chamber has a foreign matter removal mechanism, such as a strainer or a magnetic filter, so the intrusion of foreign matter into the control chamber does not pose a significant problem to the function of the belt-type continuously variable transmission. However, the lubricating fluid reservoir does not have such a foreign matter removal mechanism. Therefore, if foreign matter enters the lubricating fluid in the lubricating fluid reservoir, the final gear scoops up the lubricating fluid, scattering the foreign matter into the case. Therefore, especially if the foreign matter is larger than a certain size, it may adversely affect the mechanism of the belt-type continuously variable transmission. Therefore, it is desirable to prevent foreign matter from entering the lubricating fluid reservoir, which does not have a foreign matter removal mechanism, as much as possible. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-58519 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-129567 Summary of the Invention [Problem to be solved by the invention]

[0006] In conventional belt-type continuously variable transmissions, a baffle plate is provided between the pulley around which the belt is wound and the final gear to regulate the flow of lubricating fluid and protect the final gear from foreign matter (see, for example, Patent Document 1). The lower surface of this baffle plate opposite the final gear faces the side wall (inner wall) of the case, and conventionally there has been a small gap (gap between the case and the baffle plate) of, for example, about 3 mm between this surface and the case side wall.

[0007] Meanwhile, the lubricating liquid that has lubricated each part inside the case falls to the bottom of the case due to gravity and the centrifugal force caused by the rotation of the gears, as mentioned above. Some of this lubricating liquid is returned to the control chamber, while the other part passes through the gap between the case and the baffle plate and is returned to the lubricating liquid reservoir.

[0008] For example, if a foreign object that is expected to be present inside the case is as thick as an element, approximately 1.5 mm thick, in the conventional structure, the width of the above-mentioned gap is wider than this thickness, so there is a risk that the expected foreign object will pass through this gap and enter the lubricating liquid storage section.

[0009] It has also been proposed to provide a baffle plate with a magnet to capture and remove foreign matter in the lubricating liquid supplied to the bearing (see Patent Document 2). However, even with this structure, it is difficult to completely capture foreign matter contained in the lubricating liquid that is returned to the lubricating liquid reservoir from all routes.

[0010] The present invention has been made in consideration of the above points, and its purpose is to provide a power transmission device that can more effectively capture foreign matter that has become mixed into the lubricating liquid inside the case, thereby preventing damage to gears, bearings, etc. caused by such foreign matter. [Means for solving the problem]

[0011] In order to solve the above problem, the power transmission device (1) of the present invention comprises a case (11), a gear (32) installed in the case (11), and a baffle plate (36) provided within the case (11) between a side surface of the gear (32) and a side wall (13 a) of the case (11), wherein the case (11) contains lubricating liquid inside, and the case (11) has a narrow portion (42) in a gap (S) between the side wall (13 a) of the case (11) and the baffle plate (36) that has a clearance (g) of a predetermined dimension or less, and a lubricating liquid flow path (43) provided in at least a part of the gap (S) other than the narrow portion (42) and through which the lubricating liquid flows.

[0012] According to the power transmission device of the present invention having the above-described configuration, when the lubricating liquid passes through the narrow section between the side wall of the case and the baffle plate, foreign matter of a predetermined size or larger that has become mixed in the lubricating liquid is captured, thereby preventing large foreign matter from circulating again within the case and causing damage to gears or bearings, and also ensuring a route for the lubricating liquid to return to the storage section through the lubricating liquid flow path.

[0013] Here, the narrow portion (42) may be formed by a gap between a rib (41) protruding from the baffle plate (36) toward the side wall (13a) of the case (11) and the side wall (13a).

[0014] According to this configuration, it is possible to provide a narrow portion having a desired clearance in the gap between the side wall of the case and the baffle plate with a relatively simple configuration.

[0015] Furthermore, it is desirable that the clearance (g) be smaller than the thickness (t) of a foreign object (M) that is expected to enter the gap (S) between the side wall (13a) of the case (11) and the baffle plate (36) (t>g).

[0016] Furthermore, when the power transmission device (1) is a belt-type continuously variable transmission and the belt-type continuously variable transmission (1) has a belt (29) including an endless flexible member (29r) and a rigid member (29e), it is desirable that the clearance (g) be equal to or less than the thickness dimension (te) of the rigid member (29e) (te≧g). In one embodiment of the present invention, the clearance (g) may be smaller than 1.4 mm.

[0017] With these configurations, the lubricating liquid flowing down inside the case is allowed to pass through the gap between the side wall of the case and the baffle plate, and even if the lubricating liquid contains foreign matter larger than the clearance (for example, foreign matter of a size equivalent to part of an element of a belt for a belt-type continuously variable transmission), the foreign matter can be effectively captured in the narrow section.

[0018] Preferably, a plurality of the lubricating liquid flow paths (43) are provided in the gap (S) between the side wall (13a) of the case (11) and the baffle plate (36).

[0019] With this configuration, even if one lubricating liquid flow path is blocked by a foreign object, the lubricating liquid can pass through other lubricating liquid flow paths, ensuring a route for the lubricating liquid to return to the reservoir within the case.

[0020] Furthermore, it is preferable that the width (w) and depth (d) of the lubricating liquid flow path (43) are smaller than the smaller of the width (x) or height (y) of a foreign object (M) that is expected to enter the gap (S) between the side wall (13a) of the case (11) and the baffle plate (36).

[0021] Furthermore, when the power transmission device (1) is a belt-type continuously variable transmission (CVT) having a belt (29) including an endless flexible member (29r) and a rigid member (29e), it is preferable that the width (w) and depth (d) of the lubricating liquid flow path (43) are smaller than either the height (he) of the leg portion (29L) of the rigid member (29e) or half the distance (le / 2) from the tip of the leg portion (29L) to the base of the leg portion (29L). In one embodiment of the present invention, the width (w) and depth (d) of the lubricating liquid flow path (43) may be smaller than 5.0 mm in the gap (S).

[0022] With these configurations, even if a foreign object with dimensions larger than the width and depth of the lubricating liquid flow path (for example, a foreign object larger than the size of part of an element of a belt for a belt-type continuously variable transmission) gets mixed into the lubricating liquid, it is possible to prevent the foreign object mixed into the lubricating liquid from entering the lubricating liquid storage section and scattering back into the case, causing damage to gears and bearings.

[0023] Furthermore, it is preferable that the bottom of the case (11) has a lubricating liquid reservoir (60) in which the lubricating liquid is stored, and that the narrow portion (42) is located at a position higher than the liquid level (61) of the lubricating liquid stored in the lubricating liquid reservoir (60).

[0024] According to this configuration, since the narrow portion is located at a position higher than the liquid level of the lubricating liquid stored in the lubricating liquid storage portion, even if foreign matter is mixed into the lubricating liquid before it flows into the lubricating liquid storage portion, the foreign matter can be removed by the narrow portion, thereby effectively preventing the foreign matter from entering the lubricating liquid storage portion.

[0025] The bottom of the case (11) may have a lubricating liquid reservoir (60) in which the lubricating liquid is stored, and the gear (32) may be partially immersed in the lubricating liquid stored in the lubricating liquid reservoir (60).

[0026] According to this configuration, the lubricating liquid reservoir stores lubricating liquid from which foreign matter has been removed by the narrow section, so even if the gears scoop up the lubricating liquid in the lubricating liquid reservoir and circulate it, there is no risk of damage to the gears or bearings due to foreign matter.

[0027] Furthermore, the bottom of the case (11) has a lubricating liquid reservoir (60) in which the lubricating liquid is stored, and a control chamber (50) arranged adjacent to the lubricating liquid reservoir (60), and both the lubricating liquid reservoir (60) and the control chamber (50) are arranged along the side wall (13a) of the case (11), and it is preferable that the narrow portion (42) gradually descends and extends from a starting point (P) facing the lubricating liquid reservoir (60) on the baffle plate (36) to an end point (Q) facing the control chamber (50) when the power transmission device is in the mounted position.

[0028] In this case, it is desirable that an opening (51) for guiding the lubricating liquid into the control chamber (50) is provided at a position corresponding to the end point (Q) of the narrow portion (42).

[0029] With these configurations, the lubricating liquid that reaches the narrow portion flows along the narrow portion from the lubricating liquid reservoir side to the control chamber side, and the lubricating liquid is further guided into the control section through the opening. Therefore, even if the lubricating liquid contains foreign matter, the foreign matter trapped in the narrow portion can be guided to the control chamber. Therefore, the foreign matter can be finally captured by a capturing means such as a magnet installed in the control chamber. Meanwhile, the lubricating liquid that passes through the narrow portion is stored in the lubricating liquid reservoir and can be circulated again within the case.

[0030] In addition, the narrow portion 42 is preferably disposed above the rotation shaft 33 of the gear 32 in the installed position of the power transmission device. In addition, the narrow portion 42 is preferably disposed on a single continuous line, and in this case, the single continuous line on which the narrow portion 42 is disposed is preferably disposed from one end to the other end in the width direction of the baffle plate 36.

[0031] These configurations make it possible to capture foreign matter contained in the lubricating oil that falls at any position across the width of the baffle plate in the narrow section, thereby preventing the foreign matter from being recirculated within the case.

[0032] Furthermore, as one embodiment of the present invention, it is preferable that the baffle plate (36) is a molded product made of synthetic resin, and it is also preferable that the rib (41) gradually tapers from its base portion on the baffle plate (36) side toward the side wall (13a) of the case (11).

[0033] According to these configurations, the baffle plate made of synthetic resin and provided with ribs has excellent mold-removal properties, and therefore the baffle plate can be efficiently manufactured by injection molding or the like.

[0034] In addition, the gear (32) is preferably the gear that is provided at the lowest position in the case (11) when the power transmission device is in the mounted position.

[0035] With this configuration, the narrow section provided in the gap between the side wall of the case and the baffle plate is located below other gears that may be sources of foreign matter and is positioned between the flow path of the lubricating liquid flowing down inside the case, so that the narrow section can more effectively capture foreign matter caused by these gears.

[0036] In the power transmission device of the present invention, the case (11) may be the case of a belt-type continuously variable transmission (1), the case may be the case of a stepped automatic transmission, the case may be the case of a drive unit mounted on a hybrid vehicle using both an internal combustion engine and an electric motor as a drive source, or the case may be the case of a drive unit mounted on an electric vehicle using motor power as a drive source.

[0037] That is, in either case, the present invention is applicable to any power transmission device that has a case and a baffle plate installed within the case. [Effects of the Invention]

[0038] According to the power transmission device of the present invention, foreign matter of a predetermined size or larger that has become mixed into the lubricating liquid is captured as the lubricating liquid passes through the narrow section between the side wall of the case and the baffle plate, thereby preventing large foreign matter from circulating again and causing damage to the gears and bearings inside the case. [Brief explanation of the drawings]

[0039] [Figure 1] 3 is a front view showing the belt-type continuously variable transmission according to the embodiment of the present invention, and is a cross-sectional view taken along the line BB in FIG. 2. [Figure 2] 2 is a longitudinal cross-sectional view of the belt-type continuously variable transmission shown in FIG. 1 along the line AA. [Figure 3] 2A and 2B are explanatory diagrams showing the lubricating fluid supply route of the belt-type continuously variable transmission of FIG. 1, where (a) shows the supply route from the control room and (b) shows the supply route from the lubricating fluid reservoir. [Figure 4] 1A and 1B are diagrams showing a baffle plate, in which (a) is a front view seen from the opposite side to the final driven gear, and (b) is a DD cross-sectional view of (a). [Figure 5] FIG. 10 is a perspective view showing a state in which the baffle plate is attached to the case. [Figure 6] FIG. 3 is an enlarged view of part C in FIG. 2. [Figure 7] 7 is a cross-sectional view of FIG. 6 taken along line E-E. [Figure 8] FIG. 2 is a schematic diagram showing dimensions of a foreign object. [Figure 9] 1 is an explanatory diagram showing a rigid member and an endless flexible member of a belt for a belt-type continuously variable transmission; DETAILED DESCRIPTION OF THE INVENTION

[0040] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. Fig. 1 is a front view showing a belt-type continuously variable transmission 1 according to an embodiment of the present invention, and Fig. 2 is a longitudinal sectional view of the belt-type continuously variable transmission of Fig. 1 taken along line AA.

[0041] [Configuration and operation of power transmission device] First, the overall structure of a belt-type continuously variable transmission 1, which is a power transmission device of this embodiment, will be described with reference to Figures 1 and 2 (mainly Figure 2). The belt-type continuously variable transmission 1 is mounted on a vehicle (not shown) as a power transmission device for the vehicle. A transmission case (corresponding to the "case" of the present invention) 11 includes a torque converter case 12 connected to an engine (not shown) and a transmission case main body 13 connected to the torque converter case 12. An input shaft 14, a drive pulley shaft 15, a driven pulley shaft 16, and an idle shaft 17 are supported in parallel inside the transmission case 11.

[0042] A forward drive gear 21 engageable via a forward clutch 20 is supported for relative rotation on the input shaft 14, which is connected to the engine crankshaft 18 via a torque converter 19, and this forward drive gear 21 meshes with a forward driven gear 22 fixed to the drive pulley shaft 15. A reverse driven gear 24 engageable via a reverse clutch 23 is supported for relative rotation on the drive pulley shaft 15, and this reverse driven gear 24 meshes with a reverse drive gear 26 fixed to the input shaft 14 via an idle gear 25 supported on the idle shaft 17.

[0043] A drive pulley 27 supported on the drive pulley shaft 15 and a driven pulley 28 supported on the driven pulley shaft 16 are connected by a belt (metal belt) 29, and the rotational speed ratio between the drive pulley shaft 15 and the driven pulley shaft 16 can be changed by changing the groove width of the drive pulley 27 and the driven pulley 28.

[0044] A final drive gear 30 fixed to the driven pulley shaft 16 meshes with a final driven gear 32 fixed to the case of a differential gear 31, and left and right axles 33, 33 extend from the differential gear 31 to the outside of the transmission case 11.

[0045] Next, the operation of the belt-type continuously variable transmission (power transmission device) 1 of this embodiment configured as described above will be described.

[0046] When the forward clutch 20 is engaged and the reverse clutch 23 is disengaged, the driving force of the engine is transmitted from the crankshaft 18 to the drive wheels via the torque converter 19, the forward clutch 20, the forward drive gear 21, the forward driven gear 22, the drive pulley 27, the driven pulley 28, the final drive gear 30, the final driven gear 32, the differential gear 31, and the axles 33, 33, causing the vehicle to move forward.

[0047] Furthermore, when the forward clutch 20 is disengaged and the reverse clutch 23 is engaged, the driving force of the engine is transmitted in reverse through the crankshaft 18, torque converter 19, reverse drive gear 26, idle gear 25, reverse driven gear 24, reverse clutch 23, drive pulley 27, driven pulley 28, final drive gear 30, final driven gear 32, differential gear 31, and axles 33, 33, and is transmitted to the drive wheels, causing the vehicle to travel in reverse.

[0048] In either case of forward or reverse driving, if the groove width of the drive pulley 27 is reduced and the groove width of the driven pulley 28 is increased, the rotational speed ratio between the drive pulley shaft 15 and the driven pulley shaft 16 increases continuously, and the vehicle speed decreases. Conversely, if the groove width of the drive pulley 27 is increased and the groove width of the driven pulley 28 is reduced, the rotational speed ratio between the drive pulley shaft 15 and the driven pulley shaft 16 decreases continuously, and the vehicle speed increases.

[0049] [Configuration and operation of lubrication mechanism] In the belt-type continuously variable transmission (power transmission device) 1 of this embodiment, there are mainly two routes for lubricating fluid to flow through the transmission case 11. The first route, as shown in Fig. 3(a), is a route in which lubricating / cooling oil (such as ATF or CVTF, hereinafter referred to as "lubricating fluid") stored in a control chamber (oil pan) 50 provided in the lower part of the transmission case 11 is pumped up by an oil pump (not shown) and supplied to various parts of the belt-type continuously variable transmission 1 for lubrication and cooling.

[0050] The second route, as shown in Figure 3(b), is a route in which the lubricating liquid stored in a lubricating liquid storage section 60 separate from the control chamber 50 located at the bottom of the transmission case 11 is scooped up by the rotation of the final driven gear 32, which is partially immersed in the lubricating liquid, and scattered upward within the transmission case 11, thereby supplying the lubricating liquid to each part of the belt-type continuously variable transmission 1.

[0051] The lubricating liquid supplied to each part inside the transmission case 11 via these two routes falls inside the transmission case 11 while lubricating and cooling each part, and then flows back to the control chamber 50 or the lubricating liquid storage section 60 where it is stored again.

[0052] Here, a baffle plate 36 is provided as a structure to prevent excessive scattering of the lubricating liquid when the lubricating liquid stored in the lubricating liquid storage section 60 is scooped up by the final driven gear 32, and to protect the bearings, final driven gear 32, etc. from foreign matter that may be contained in the lubricating liquid returned to the lubricating liquid storage section 60. This baffle plate 36 is fixed to the transmission case main body 13 and the input shaft holder (not shown) so as to cover the upper half of the final driven gear 32 and the final drive gear 30 attached to the driven pulley shaft 16.

[0053] 4 shows the baffle plate 36, where (a) is a front view seen from the opposite side of the final driven gear 32, and (b) is a DD cross-sectional view with part of the background omitted. In this figure, the side wall 13a of the adjacent transmission case 11 (hereinafter referred to as the "case side wall 13a") is also shown by a two-dot chain line. The baffle plate 36 is a member integrally molded from synthetic resin, and is fixed to the transmission case main body 13 with bolts 37 and 38. The baffle plate 36 has an upper drive gear cover portion 39 and a lower driven gear cover portion 40.

[0054] The upper drive gear cover portion 39 corresponds to the final drive gear 30 (see FIG. 2) fixed to the driven pulley shaft 16 and the ball bearing 34 (see FIG. 2) that supports the right end of the driven pulley shaft 16, and is disposed axially between the driven pulley 28 and the final drive gear 30 (see FIG. 2). A circular opening 39a through which the driven pulley shaft 16 passes is formed in the center of the drive gear cover portion 39, and an arc-shaped side wall 39b, an outer peripheral wall 39c extending along the outer periphery of the side wall 39b, and the like are formed in the upper half of the opening 39a.

[0055] The lower driven gear cover portion 40 corresponds to the final driven gear 32 and has a semicircular side wall portion 40a that is arranged to sandwich the upper half of the final driven gear 32, an opening 40b through which the axle 33 passes is formed in the center of the side wall portion 40a, and a first outer peripheral wall and a second outer peripheral wall that connect to both circumferential ends of the outer peripheral wall 39c of the drive gear cover portion 39 are formed on the outer periphery of the side wall portion 40a.

[0056] The side wall portion 40a has two tiers of oil guide walls 40e, 40f (see Figures 4 and 5) extending diagonally downward toward the bottom of the transmission case 11 on the surface opposite to the surface on which the first outer peripheral wall 40c and the second outer peripheral wall 40d are formed, i.e., on the surface on the transmission case main body 13 side, and the upper ends of the oil guide walls 40e, 40f face the oil discharge hole 39i of the drive gear cover portion 39.

[0057] Figure 5 is a perspective view showing the baffle plate 36 attached to the transmission case main body 13. The baffle plate 36 is in the same position as in Figure 4(a), with its lower half positioned opposite the case side wall 13a of the transmission case main body 13. Although not shown in Figure 5, the final drive gear 30 and final driven gear 32 are positioned on the opposite side of the baffle plate 36 (the back side of the figure), with the driven pulley shaft 16 positioned through an opening 39a in the baffle plate 36 and the axle 33 positioned through an opening 13b in the case side wall 13a.

[0058] Here, in the baffle plate 36 of the belt-type continuously variable transmission (power transmission device) 1 of this embodiment, a rib 41 protruding from the baffle plate 36 toward the case side wall 13a is provided on the lower side of the oil guide walls 40e, 40f in the driven gear cover portion 40, facing the case side wall 13a of the transmission case 11, and a narrow portion 42 is formed in the gap between the rib 41 and the case side wall 13a.

[0059] Fig. 6 is a partially enlarged view of part C in Fig. 2, showing the narrow portion 42 and its vicinity. Fig. 7 is a cross-sectional view taken along the line E-E in Fig. 6. As shown in these figures, the clearance g between the rib 41 and the case side wall 13a in the narrow portion 42 is formed to have a predetermined dimension, so that when the lubricating liquid passes through the narrow portion 42 provided in the gap S between the case side wall 13a and the baffle plate 36, foreign matter of a predetermined size or larger that has become mixed in the lubricating liquid is captured.

[0060] In this embodiment, the clearance g of the narrow portion 42 is set to a dimension less than the thickness t of the foreign matter M so that foreign matter, particularly thin plate-like foreign matter (see Figure 8), which is expected to enter the gap S between the case side wall 13a and the baffle plate 36, does not pass through the narrow portion 42.

[0061] 9 shows the rigid member (element) 29e and the endless flexible member 29r of the belt 29 of the belt-type continuously variable transmission 1. In this embodiment, it is desirable to prevent foreign matter having a thickness t equal to or greater than the thickness te of the rigid member (element) 29e from passing through the narrow portion 42. As an example of a specific dimension for this purpose, the clearance g of the narrow portion 42 can be set to 1.4 mm or less.

[0062] With this configuration, even if a foreign object having a thickness similar to the thickness te of the rigid member (element) 29e constituting the belt 29 of the belt-type continuously variable transmission 1 is mixed into the lubricating liquid in the transmission case 11, the foreign object can be prevented from flowing into the lubricating liquid storage section 60 along with the lubricating liquid.

[0063] 7, in this embodiment, lubricating liquid flow paths 43 that allow only the lubricating liquid to pass but not foreign matter to pass are provided at multiple locations between narrow portions 42 in the gap between the case side wall 13a and the baffle plate 36. With this configuration, an appropriate amount of lubricating liquid can be returned to the lubricating liquid reservoir 60.

[0064] In order to ensure a certain flow rate of lubricating liquid, the lubricating liquid flow path 43 has a depth d (the dimension from the case side wall 13a to the inner surface of the lubricating liquid flow path 43 in the baffle plate 36) that is larger than the clearance g, but the width w (the length in the surface direction of the baffle plate 36) and depth d of the lubricating liquid flow path 43 are set smaller than the smaller dimension of the width x or height y of a foreign object M (see Figure 8) that is expected to enter the gap S between the case side wall 13a and the baffle plate 36.

[0065] In this embodiment, the lubricating liquid flow path 43 is configured so that foreign matter M having dimensions greater than either the height he of the leg portion 29L of the rigid member (element) 29e (see FIG. 9) constituting the belt 29 (see FIGS. 1 and 2) of the belt-type continuously variable transmission, or half the distance le (le / 2) from the tip of the leg portion 29L of the rigid member (element) 29e to the base of the leg portion 29L of the rigid member (element) cannot pass through the lubricating liquid flow path 43. As an example of specific dimensions, the width w and depth d of the lubricating liquid flow path 43 can be set to dimensions smaller than 5.0 mm.

[0066] In this embodiment, the control chamber 50 and the lubricating liquid reservoir 60 are disposed adjacent to each other and share the case side wall 13a (see FIG. 5). That is, the lubricating liquid reservoir 60 and the control chamber 50 are disposed adjacent to each other at the bottom of the transmission case 11, and both the lubricating liquid reservoir 60 and the control chamber 50 are disposed along the case side wall 13a. In other words, a portion of the inner surfaces (inner walls) of the lubricating liquid reservoir 60 and the control chamber 50 are formed by the case side wall 13a.

[0067] The narrow portion 42 is formed at a position higher than a liquid level 61 of the lubricating liquid stored in the lubricating liquid storage portion 60 (the highest position of the liquid level 61 in the lubricating liquid storage portion 60) (see FIG. 1). As shown in FIG. 5, the narrow portion 42 extends gradually downward from a start point P, which faces the lubricating liquid storage portion 60 on the baffle plate 36, to an end point Q, which faces the control chamber 50, when the belt-type continuously variable transmission 1 is mounted on the vehicle. A control chamber inlet (opening) 51 is provided at a position corresponding to the end point Q of the narrow portion 42, for guiding the lubricating liquid that has flowed down through the narrow portion 42 into the control chamber 50.

[0068] According to this configuration, the lubricating liquid that reaches the narrow portion 42 flows along the narrow portion 42 from the lubricating liquid reservoir 60 side to the control chamber 50 side, and the lubricating liquid is further guided into the control chamber 50 via the control chamber inlet 51. Therefore, even if the lubricating liquid contains foreign matter, the foreign matter captured in the narrow portion 42 can be guided into the control chamber 50. As a result, the foreign matter can be finally captured by a capturing means such as a magnet provided in the control chamber 50. Meanwhile, the lubricating liquid that passes through the narrow portion 42 is stored in the lubricating liquid reservoir 60 and can be circulated again within the transmission case 11.

[0069] 4 and 5, the rib 41 (narrow portion 42) is disposed above the rotation shaft (axle 33) of the final driven gear 32. The narrow portion 42 is disposed on a single continuous line that extends from one end to the other in the width direction of the baffle plate 36. This configuration makes it possible for foreign matter contained in the lubricating oil that has fallen to any position in the width direction of the baffle plate 36 to be captured by the narrow portion 42, thereby preventing the foreign matter from being recirculated within the transmission case 11.

[0070] Furthermore, the baffle plate 36 of this embodiment is a molded product made of synthetic resin, and the ribs 41 that form the narrow portion 42 gradually become thinner from their bases on the baffle plate 36 side toward the case side wall 13a. This configuration allows the baffle plate 36 with the ribs 41 to be efficiently manufactured by injection molding or the like, and also makes it easy to remove from the mold.

[0071] Next, we will explain the operation of the lubrication mechanism of the belt-type continuously variable transmission (power transmission device) 1 of this embodiment configured as described above. As shown in Figure 3(a), lubricating liquid stored in a control chamber 50 (oil pan) provided in the lower part of the transmission case 11 is pumped up by an oil pump (not shown) and supplied to various parts of the belt-type continuously variable transmission (power transmission device) 1 for lubrication and cooling.

[0072] 3(b), when the vehicle travels forward, the final driven gear 32 of the belt-type continuously variable transmission 1 rotates in the direction of the arrow inside the transmission case 11, so that the lubricating fluid stored in the lubricating fluid reservoir 60 at the bottom of the transmission case 11 is scooped up into the driven gear cover portion 40 of the baffle plate 36 by the final driven gear 32, and some of the lubricating fluid flows into the drive gear cover portion 39 of the baffle plate 36 to lubricate the final drive gear 30 and ball bearing 34 (see FIG. 2) as well as the inside of the differential gear 31. Another portion of the lubricating fluid flows out from gaps between the driven gear cover portion 40 and the drive gear cover portion 39 of the baffle plate 36 and travels through the driven pulley 28, bearing 35, and belt 29 attached to the driven pulley shaft 16 inside the transmission case 11 shown in FIG. 2, to lubricate the drive pulley 27 and gears 21, 22, 24, 25, etc.

[0073] The lubricating liquid supplied to each part inside the transmission case 11 via the above two routes falls by gravity while lubricating and cooling each part, and most of it is returned to the control chamber 50. The remaining part is returned to the lubricating liquid reservoir 60 (see FIGS. 1 and 2), mainly passing through the gap S between the baffle plate 36 and the case side wall 13a shown in FIG. 6.

[0074] Most of the lubricating liquid that attempts to flow into the gap S between the baffle plate 36 and the case side wall 13a flows into the control chamber 50 from the control chamber inlet 51 along the upper and lower two-tier oil guide walls 40e, 40f of the baffle plate 36, as shown by the arrows in Figure 5, but some of the lubricating liquid flows around to the underside of the lower tier oil guide wall 40f and flows into the gap S between the baffle plate 36 and the case side wall 13a.

[0075] As shown in FIG. 6, a rib 41 is provided in the gap S, protruding from the baffle plate 36 toward the case side wall 13a, and a narrow portion 42 is formed between the case side wall 13a and the rib 41.

[0076] As shown in Figure 5, this rib 41 (narrow portion 42) is inclined so as to gradually descend from the lubricating liquid storage portion 60 side toward the control chamber 50 side, so that some of the lubricating liquid that flows into the gap S between the baffle plate 36 and the case side wall 13a flows along the rib 41 (narrow portion 42) from the control chamber entrance 51 into the control chamber 50.

[0077] Another portion of the lubricating liquid passes through the narrow portion 42 shown in Figure 6 and flows back into the lubricating liquid storage portion 60. As mentioned above, the clearance g between the rib 41 and the case side wall 13a in this narrow portion 42 is set to a predetermined value so that foreign matter of a predetermined size or larger that has become mixed into the lubricating liquid is captured as the lubricating liquid passes through the narrow portion 42.

[0078] The lubricating liquid also passes through a plurality of lubricating liquid flow paths 43 having a depth d greater than the clearance g of the narrow portion 42, but foreign matter of a predetermined size or larger is trapped without passing through these lubricating liquid flow paths 43. As a result, only clean lubricating liquid from which foreign matter of a predetermined size or larger has been removed flows back into the lubricating liquid reservoir 60.

[0079] The trapped foreign matter flows into the control chamber 50 together with the lubricating liquid (lower arrow in Figure 5) that flows along the ribs 41 that form the narrow portion 42. The lubricating liquid that has returned to the control chamber 50 is sent again to each part by a pump (not shown) and is used for lubrication and cooling, but because the control chamber 50 is equipped with a foreign matter capturing means (not shown) such as a magnet, the foreign matter is ultimately captured here and does not damage the gears, bearings, etc. of the belt-type continuously variable transmission (power transmission device) 1.

[0080] Although the embodiment of the present invention has been described above, various design modifications can be made to the present invention without departing from the gist of the invention.

[0081] For example, in the above embodiment, the narrow portion 42 is formed by a rib 41 protruding from the baffle plate 36 toward the case side wall 13a, but the narrow portion 42 may also be formed by a structure other than a rib, for example, a structure having a planar or linear expansion.

[0082] In the above embodiment, the baffle plate 36 is an injection-molded product made of synthetic resin, but it may be made of a material other than synthetic resin, and may be formed by a method other than injection molding.

[0083] Furthermore, the power transmission device of the present invention is not limited to the belt-type continuously variable transmission 1 shown in the above embodiment, but may be a stepped automatic transmission, a power transmission device mounted on a hybrid vehicle using both an internal combustion engine and an electric motor as drive sources, or a power transmission device mounted on an electric vehicle. In any of these cases, the present invention is applicable as long as the power transmission device has a case and a baffle plate installed in the case. [Explanation of symbols]

[0084] 1 Belt-type continuously variable transmission (power transmission device) 11 Transmission case (case) 12 Torque converter case 13 Transmission case body 13a Side wall (case side wall) 13b opening 14 Input shaft 15 Drive pulley shaft 16 Driven pulley shaft 17 Idle shaft 18 crankshaft 19 Torque converter 20 Forward clutch 21 Forward drive gear 22 Forward driven gear 23 Reverse clutch 24 Reverse driven gear 25 Idle Gear 26 Reverse drive gear 27 Drive pulley 28 Driven pulley 29 Metal Belt (Belt) 29r endless flexible member 29e Rigid member (element) 29L Leg 30 Final drive gear 31 Differential gear 32 Final driven gear 33 Axle (rotating shaft) 36 Baffle plate 39 Drive gear cover 39a opening 39b side wall 39c outer wall 39i Oil drain hole 40 Driven gear cover part 4 40a Side wall 40b opening 40c 1st outer wall 40d 2nd outer wall 40e, 40f Oil guide wall 41 Ribs 42 Narrow area 43 Lubricant flow path 50 Control Room 51 Control room entrance (opening) 60 Lubricant reservoir 61 Liquid level S: Gap (between the side wall 13a and the baffle plate 36) M Foreign object d Depth (of lubricant flow path) g Clearance he (leg) height le (distance from tip to base of leg) t (foreign substance) thickness te (element) thickness w width (of lubricant flow path) x (foreign object) width y (foreign object) height

Claims

1. Case and a gear installed in the case; a baffle plate provided in the case between a side surface of the gear and a side wall of the case, The case contains a lubricating liquid therein, a narrow portion having a clearance of a predetermined dimension or less in a gap between the side wall of the case and the baffle plate, and a lubricating liquid flow path provided in at least a part of the gap other than the narrow portion, through which the lubricating liquid flows, The power transmission device is a belt-type continuously variable transmission, and the belt-type continuously variable transmission has a belt configured to include an endless flexible member and a rigid member, and the clearance is a dimension that is equal to or smaller than the thickness dimension of the rigid member. A power transmission device characterized by:

2. A case, a gear installed in the case; a baffle plate provided in the case between a side surface of the gear and a side wall of the case, The case contains a lubricating liquid therein, a narrow portion having a clearance of a predetermined dimension or less in a gap between the side wall of the case and the baffle plate, and a lubricating liquid flow path provided in at least a part of the gap other than the narrow portion, through which the lubricating liquid flows, the power transmission device is a belt-type continuously variable transmission, and the belt-type continuously variable transmission has a belt configured to include an endless flexible member and a rigid member, The width and depth of the lubricating liquid flow path are smaller than either the height of the leg portion of the rigid member or half the distance from the tip of the leg portion to the base of the leg portion. A power transmission device characterized by:

3. A case, a gear installed in the case; a baffle plate provided in the case between a side surface of the gear and a side wall of the case, The case contains a lubricating liquid therein, a narrow portion having a clearance of a predetermined dimension or less in a gap between the side wall of the case and the baffle plate, and a lubricating liquid flow path provided in at least a part of the gap other than the narrow portion, through which the lubricating liquid flows, a lubricating liquid reservoir in which the lubricating liquid is stored and a control chamber disposed adjacent to the lubricating liquid reservoir at the bottom of the case; the lubricating liquid reservoir and the control chamber are both disposed along the side wall of the case; The narrow portion extends gradually downward from a start point facing the lubricating liquid reservoir on the baffle plate to an end point facing the control chamber when the power transmission device is in an installed position. A power transmission device characterized by:

4. An opening for guiding the lubricating liquid into the control chamber is provided at a position corresponding to the end point of the narrow portion.

4. The power transmission device according to claim 3.

5. A case; a gear installed in the case; a baffle plate provided in the case between a side surface of the gear and a side wall of the case, The case contains a lubricating liquid therein, a narrow portion having a clearance of a predetermined dimension or less in a gap between the side wall of the case and the baffle plate, and a lubricating liquid flow path provided in at least a part of the gap other than the narrow portion, through which the lubricating liquid flows, The narrow portion is disposed above the rotation shaft of the gear in the mounted posture of the power transmission device. A power transmission device characterized by:

6. The narrow portion is formed by a gap between a rib protruding from the baffle plate toward the side wall of the case and the side wall.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

7. The clearance is smaller than the thickness of a foreign object that is expected to enter the gap between the side wall of the case and the baffle plate.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

8. The clearance is smaller than 1.4 mm.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

9. A plurality of the lubricating liquid flow paths are provided in the gap.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

10. The width and depth of the lubricating liquid flow path are smaller than the smaller of the width and height of a foreign object that is expected to enter the gap between the side wall of the case and the baffle plate.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

11. The lubricating fluid flow path has a width and depth of less than 5.0 mm in the gap.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

12. a lubricating liquid reservoir in which the lubricating liquid is stored is provided at the bottom of the case; The narrow portion is located at a position higher than the liquid level of the lubricating liquid stored in the lubricating liquid storage portion.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

13. The bottom of the case has a lubricating liquid reservoir in which the lubricating liquid is stored, The gear is partially immersed in the lubricating liquid stored in the lubricating liquid storage section.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

14. The narrow portions are arranged in a single continuous line.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

15. The single continuous line on which the narrow portion is arranged is arranged from one end to the other end in the width direction of the baffle plate.

15. The power transmission device according to claim 14.

16. The baffle plate is a molded product made of synthetic resin.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

17. The rib is gradually tapered from its base on the baffle plate side toward the side wall of the case.

7. The power transmission device according to claim 6.

18. The gear is a gear that is provided at the lowest position in the case when the power transmission device is mounted.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

19. the power transmission device is a belt-type continuously variable transmission, The case accommodates components of the belt-type continuously variable transmission.

6. The power transmission device according to claim 1, wherein the power transmission device is a power transmission device.

20. the power transmission device is a stepped automatic transmission, The case accommodates components of the stepped automatic transmission.

6. The power transmission device according to claim 3, wherein the power transmission device is a power transmission device having a first end and a second end.

21. the power transmission device is a drive device mounted on a hybrid vehicle that uses both an internal combustion engine and an electric motor as drive sources, The case is a case that houses components of the drive device.

6. The power transmission device according to claim 3, wherein the power transmission device is a power transmission device having a first end and a second end.

22. the power transmission device is a drive device mounted on an electric vehicle using an electric motor as a drive source, The case is a case that houses components of the drive device.

6. The power transmission device according to claim 3, wherein the power transmission device is a power transmission device having a first end and a second end.

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