Power transmission

Abstract

[Problem] To reduce the number of bolts, which are needed for coupling parts constituting a baffle plate, to one. [Solution] A space in a case in which oil is stored is divided, by a baffle plate, into a first space in which a driven sprocket mounted on an input shaft of an oil pump is disposed, and a second space in which an oil strainer communicating with the oil pump is disposed. At least a portion of the driven sprocket is immersed in the oil in the first space. The baffle plate is constituted by a base part, and a cover part that is coupled to the base plate and covers the driven sprocket. The base part and the cover part are engaged together by an engagement piece extending from one of the base part and the cover part and engaging with an outer surface of the other, and are coupled together by a bolt at a position different from the engagement position of the engagement piece.

Description

[Technical field]

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

[0002] Patent Document 1 discloses a configuration in which the driven sprocket of a chain-driven oil pump is immersed in oil stored in a case, and the drive sprocket, driven sprocket, and chain are lubricated.

[0003] Furthermore, in this configuration, the baffle plate divides the space in which the oil is stored into a space in which the driven sprocket is located and a space in which the oil strainer is located, thereby preventing the oil pump from sucking in air in the oil through the oil strainer, which increases when the driven sprocket and chain stir the oil. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-102818 A Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the baffle plate is composed of a baffle plate main body part and a baffle plate cover part attached to the baffle plate main body part, and the two are joined by bolting at two points.

[0006] In order to bolt the two points, it is necessary to secure two spaces around the baffle plate, specifically spaces to accommodate the bolt heads and tools. However, it may be difficult to secure such spaces in relation to other parts placed around the baffle plate.

[0007] The present invention has been made in consideration of these technical problems, and has an object to reduce the number of bolts required to connect the components that make up a baffle plate to one. [Means for solving the problem]

[0008] According to one aspect of the present invention, there is provided a power transmission device in which the space in a case in which oil is stored is divided by a baffle plate into a first space in which a driven sprocket attached to the input shaft of an oil pump is positioned and a second space in which an oil strainer communicating with the oil pump is positioned, and at least a portion of the driven sprocket is immersed in oil in the first space, wherein the baffle plate is composed of a base portion and a cover portion connected to the base portion and covering the driven sprocket, and the base portion and the cover portion are engaged with each other by an engagement piece extending from one and engaging with the outer surface of the other, and are connected to each other by a bolt at a position different from the engagement position of the engagement piece. Effect of the Invention

[0009] According to the above aspect, the number of bolts required to connect the base and cover parts that constitute the baffle plate is one. This eliminates the need to secure multiple spaces for bolt fastening in relation to other parts arranged around the baffle plate, and makes it possible to connect the base and cover parts even when it is difficult to secure such spaces in relation to other parts arranged around the baffle plate. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram for explaining the general configuration of a vehicle equipped with a power transmission device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a view of the inside of the power transmission device as seen from the case cover side. [Diagram 3]FIG. 3 is a schematic cross-sectional view taken along line III-III of FIG. [Figure 4] FIG. 4 is a perspective view of the base portion. [Diagram 5] FIG. 5 is a perspective view of the cover portion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a vehicle 100 equipped with a power transmission device 10 according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0012] Fig. 1 is a schematic diagram for explaining a general configuration of a vehicle 100. As shown in Fig. 1, the vehicle 100 includes an engine 1 and a power transmission device 10 provided in a power transmission path connecting the engine 1 and drive wheels 9.

[0013] The power transmission device 10 is a belt-type continuously variable transmission that includes a variator 20, a forward / reverse switching mechanism 30, a torque converter 40, a gear power transmission mechanism 50, a differential gear device 60, an oil pump (OP) 70, a chain power transmission mechanism 80, a case 90, and a case cover 93 that is attached to the opening of the case 90.

[0014] In the vehicle 100, rotation generated by the engine 1 is transmitted to drive wheels 9 via a torque converter 40, a forward / reverse switching mechanism 30, a variator 20 serving as a speed change mechanism, a gear power transmission mechanism 50, and a differential gear device 60.

[0015] The torque converter 40 has a lock-up clutch 41. When the lock-up clutch 41 is engaged, the input shaft 42 and the output shaft 43 of the torque converter 40 are directly connected, so that the input shaft 42 and the output shaft 43 rotate at the same speed.

[0016] The variator 20 has a primary pulley 21 and a secondary pulley 22 arranged so that their V-grooves are aligned, and a belt 23 stretched over the V-grooves of the pulleys 21 and 22.

[0017] The engine 1 is disposed coaxially with the primary pulley 21, and a torque converter 40 and a forward / reverse switching mechanism 30 are provided between the engine 1 and the primary pulley 21 in this order from the engine 1 side.

[0018] The forward / reverse switching mechanism 30 has as its main component a double pinion planetary gear set 31, whose sun gear is coupled to an output shaft 43 of a torque converter 40 and whose carrier is coupled to the primary pulley 21 of the variator 20. The forward / reverse switching mechanism 30 further includes a forward clutch 32 that directly connects the sun gear and carrier of the double pinion planetary gear set 31, and a reverse brake 33 that fixes the ring gear. When the forward clutch 32 is engaged, the input rotation from the output shaft 43 is transmitted to the primary pulley 21 in the same rotational direction, and when the reverse brake 33 is engaged, the input rotation from the output shaft 43 is reversed and transmitted to the primary pulley 21.

[0019] The forward clutch 32 is engaged by being supplied with clutch pressure from a hydraulic control valve unit (not shown) when a forward driving mode is selected as the driving mode of the vehicle 100. The reverse brake 33 is engaged by being supplied with brake pressure from a hydraulic control valve unit when a reverse driving mode is selected as the driving mode of the vehicle 100.

[0020] The rotation of the primary pulley 21 is transmitted to the secondary pulley 22 via a belt 23, and the rotation of the secondary pulley 22 is transmitted to the drive wheels 9 via an output shaft 24, a gear power transmission mechanism 50, and a differential gear device 60.

[0021] In order to make it possible to change the gear ratio between the primary pulley 21 and the secondary pulley 22 during the above-mentioned power transmission, one of the conical plates forming the V-grooves of the primary pulley 21 and the secondary pulley 22 is a fixed conical plate 21a, 22a, and the other is a movable conical plate 21b, 22b that can be displaced in the axial direction.

[0022] The primary pulley 21 and the secondary pulley 22 operate in response to the oil pressure of the oil supplied from the control valve unit 95 to the oil chamber of the primary pulley 21 and the oil chamber of the secondary pulley 22 .

[0023] Specifically, when primary pulley pressure and secondary pulley pressure are applied to the oil chambers of the primary pulley 21 and the secondary pulley 22, respectively, the movable conical plates 21b, 22b are urged toward the fixed conical plates 21a, 22a, and power is transmitted between the primary pulley 21 and the secondary pulley 22 by frictional engagement between the belt 23 and the conical plates.

[0024] During gear shifting, the width of the V-grooves of both pulleys 21, 22 changes due to the pressure difference between the primary pulley pressure and the secondary pulley pressure generated in accordance with the target gear ratio, and the winding arc diameter of belt 23 around pulleys 21, 22 changes continuously, thereby realizing the target gear ratio.

[0025] The gear power transmission mechanism 50 comprises a first gear 51 provided on the output shaft 24 of the variator 20, a second gear 52 and a third gear 53 provided on an intermediate shaft 55, and a fourth gear 54 fixed to the differential gear device 60.

[0026] The case 90 includes an intermediate wall 91 and an intermediate cover 92 attached to an opening of the intermediate wall 91 (FIG. 2). The intermediate wall 91 is a wall perpendicular to the axial direction of the output shaft 43 etc., and divides the inside of the case 90 into a space that houses the pulleys 21, 22 and the forward / reverse switching mechanism 30 and a space that houses the gear power transmission mechanism 50 and the chain power transmission mechanism 80. Oil is stored in the bottom of the case 90. In other words, the case 90 forms an oil bath in which oil is stored.

[0027] The intermediate cover 92 is provided between the torque converter 40 and the forward / reverse switching mechanism 30 so as to cover the torque converter 40 side of the forward / reverse switching mechanism 30 .

[0028] The chain power transmission mechanism 80 includes a drive sprocket 82 that is rotatably supported on the intermediate cover 92 via a bush 81, a driven sprocket 83 that is provided on the input shaft 71 of the oil pump 70, and a chain 84 that connects the drive sprocket 82 and the driven sprocket 83.

[0029] The drive sprocket 82 is connected to the output shaft 43 of the torque converter 40 via a connecting member 85. As a result, when the output shaft 43 of the torque converter 40 rotates, the oil pump 70 is driven and oil is supplied to the control valve unit 95.

[0030] The case cover 93 is fixed to the case 90 so as to cover the gear power transmission mechanism 50 and the chain power transmission mechanism 80.

[0031] Next, the internal configuration of the power transmission device 10 will be described in detail with reference to FIGS.

[0032] 2 is a view of the inside of the power transmission device 10 as viewed from the case cover 93 side. The left-right direction in FIG. 2 corresponds to the front-rear direction of the vehicle 100 (the right direction is the front direction), and the direction perpendicular to the paper surface corresponds to the left-right direction of the vehicle 100 (the depth direction into the paper surface is the left direction). In addition, a solid arrow G indicates the direction of gravity, and a dashed dotted line indicates the height of the oil level O of the oil stored in the case 90.

[0033] As shown in FIG. 2, on the rear side of the vehicle 100 in the power transmission device 10 (the left side in the figure), a gear power transmission mechanism 50 and a differential gear unit 60 are supported by a case 90.

[0034] At the front side of the vehicle 100 in the power transmission device 10, a chain power transmission mechanism 80 is supported by a case 90.

[0035] The forward / reverse switching mechanism 30 and the primary pulley 21 are located to the left of the vehicle 100 (to the rear of the page) relative to the drive sprocket 82 of the chain power transmission mechanism 80, and are not shown in FIG.

[0036] The intermediate cover 92 is secured to the intermediate wall 91 by a number of bolts 94 .

[0037] A drive sprocket 82 is rotatably supported by the intermediate cover 92 via a bush 81. A driven sprocket 83 is disposed below the drive sprocket 82. The drive sprocket 82 and the driven sprocket 83 are connected by a chain 84.

[0038] Further, the driven sprocket 83 is almost entirely covered by a bag-shaped baffle plate 86 that is open vertically upward. The space in the case 90 where the oil is stored is divided by the baffle plate 86 into a first space R1 in which the driven sprocket 83 is disposed and a second space R2 in which an oil strainer 72 that communicates with the oil pump 70 (described later) is disposed.

[0039] A vertically lower portion of the driven sprocket 83 is immersed in oil in the first space R1, thereby lubricating the chain power transmission mechanism 80.

[0040] In addition, by separating the first space R1 from the second space R2 by the baffle plate 86, the air in the oil, which increases when the driven sprocket 83 and the chain 84 stir the oil in the first space R1, is prevented from flowing into the second space R2, and the oil pump 70 is prevented from sucking in air through the oil strainer 72 located in the second space R2.

[0041] Fig. 3 is a schematic cross-sectional view taken along line III-III in Fig. 2, and shows by dashed lines the configuration other than the baffle plate 86. As shown in Fig. 3, the baffle plate 86 is composed of a base portion 87 and a cover portion 88 that is connected to the base portion 87 and covers the driven sprocket 83.

[0042] The driven sprocket 83 is attached to the input shaft 71 of the oil pump 70 through an opening 87a in the base portion 87. The rotation of the drive sprocket 82 is transmitted to the driven sprocket 83 through a chain 84, and when the driven sprocket 83 rotates, the oil pump 70 is driven.

[0043] FIG. 4 shows the base portion 87 .

[0044] The base portion 87 is made of metal and manufactured by pressing, and is composed of a base plate 87b and a chain cover portion 87c.

[0045] The base plate 87b is disposed parallel to the side surface of the driven sprocket 83 (a surface perpendicular to the rotation axis of the driven sprocket 83), and has an opening 87a in the center through which the input shaft 71 of the oil pump 70 passes.

[0046] The chain cover portion 87c is configured with a substantially arc-shaped chain cover portion 87c that extends perpendicularly to the base plate 87b from the outer edge portion of the base plate 87b and covers the entire meshing portion between the driven sprocket 83 and the chain 84. The chain cover portion 87c may be provided on the cover portion 88 instead of the base portion 87.

[0047] The base plate 87b has bolt holes 87d and 87e for inserting bolts 96 (see FIG. 2) for fixing the base portion 87 to the case 90.

[0048] The chain cover portion 87c has a tab 87f that extends outwardly and parallel to the base plate 87b. The tab 87f has a bolt hole 87g for inserting a bolt 89 (see FIG. 2) that fastens the base portion 87 and the cover portion 88 together to the case 90, thereby joining the base portion 87 and the cover portion 88 and fixing them to the case 90.

[0049] FIG. 5 shows the cover part 88 .

[0050] The cover portion 88 is made of metal and manufactured by pressing. The cover portion 88 has a cover plate 88a and a clip 88c as an engagement piece.

[0051] The cover plate 88 a is disposed parallel to the side surface of the driven sprocket 83 and the base plate 97 b of the base portion 87 .

[0052] The clip 88c extends perpendicularly to the cover plate 88a from the outer edge thereof and is bent midway to form an L-shaped cross section at an internal angle of less than 90 degrees. The clip 88c has a contact portion 88b that is pressed against the outer surface of the base portion 87 (the surface of the base portion 87 or the base plate 87b facing the case 90) when the cover portion 88 is attached to the base portion 87.

[0053] The distance between the abutment portion 83b and the cover plate 88a is approximately equal to the width of the chain cover portion 87c at the outer edge of the cover plate 88a. Moreover, except for a tip portion 88g that is bent in a direction away from the cover plate 88a, this distance becomes smaller than the width of the chain cover portion 87c as it moves from the outer edge of the cover plate 88a toward the inside of the cover portion 88. As a result, when the clip 88c is engaged with the outer surface of the base portion 87, the clip 88c is elastically deformed, and a spring force is generated by the clip 88c that presses the base portion 87 and the cover portion 88 against each other.

[0054] Furthermore, the cover portion 88 has a tab 88d that extends outwardly and parallel to the cover plate 88a at the outer edge of the cover plate 88a. The tab 88d has a bolt hole 88e for inserting a bolt 89 (see FIG. 2) that fastens the base portion 87 and the cover portion 88 together to the case 90, thereby joining the base portion 87 and the cover portion 88 and fixing them to the case 90. The tab 88d and the bolt hole 88e are provided at a position different from the clip 88c, more specifically, on the outer edge of the cover plate 88a on the opposite side to the clip 88c across approximately the center of the cover plate 88a.

[0055] The cover portion 88 also has a support portion 88f that extends perpendicularly to the cover plate 88a from the outer edge of the cover plate 88a and that comes into surface contact with the chain cover portion 87c when the base portion 87 and the cover portion 88 are joined together.

[0056] The base portion 87 and the cover portion 88 are constructed as described above, and when the baffle plate 86 is attached to the case 90, the base portion 87, the driven sprocket 83 and the chain 84, and the cover portion 88 are attached to the case 90 in this order.

[0057] Next, a procedure for attaching the cover portion 88 to the base portion 87 will be described.

[0058] When attaching the cover portion 88 to the base portion 87, first the clip 88c is engaged with the outer surface of the base portion 87. At the portion of the base portion 87 where the clip 88c engages, a gap large enough to insert the abutment portion 83b of the clip 88c is formed between the base portion 87 and the case 90, so that the clip 88c does not interfere with the case 90. In addition, because the clip 88c engages with the base portion 87 from the outside of the base portion 87, it does not interfere with the driven sprocket 83 and the chain 84 that are arranged inside the base portion 87.

[0059] At this time, the support portion 88f comes into surface contact with the chain cover portion 87c, so that the cover portion 88 can be roughly positioned with respect to the base portion 87. Moreover, compared to the case where only the clip 88c is engaged with the outer surface of the base portion 87, the posture of the cover portion 88 can be stabilized.

[0060] When the clip 88c is engaged with the outer surface of the base portion 87, the spring force of the clip 88c presses the base portion 87 and the cover portion 88 against each other and engages them.

[0061] Next, cover portion 88 is slid in the planar direction to align bolt hole 88e with bolt hole 87g of base portion 87 and bolt hole (not shown) of case 90. Then, base portion 87 and cover portion 88 are fastened together to case 90 with bolt 89 (see FIG. 2), thereby joining base portion 87 and cover portion 88 to each other and fixing them to case 90.

[0062] The spring force of the clip 88c presses the base portion 87 and the cover portion 88 against each other, thereby reducing the gap between the base portion 87 and the cover portion 88, specifically, the gap between the end of the chain cover portion 87c and the outer edge of the cover plate 88a, thereby ensuring an appropriate seal between the base portion 87 and the cover portion 88. This prevents air in the oil, which increases when the driven sprocket 83 and the chain 84 stir the oil stored in the case 90, from flowing out into the second space R2 in which the strainer 72 is disposed, thereby preventing the oil pump 70 from sucking in air through the oil strainer 72.

[0063] The base portion 87 and the cover portion 88 are directly pressed against each other, but the clip 88c elastically deforms to appropriately adjust the pressing force. Therefore, even if there is a dimensional error in the base portion 87 or the cover portion 88, the clip 88c elastically deforms to absorb it, so that excessive force is not applied to the base portion 87 or the cover portion 88 as in the case of fastening multiple points with bolts, and plastic deformation of the base portion 87 and the cover portion 88 can be suppressed.

[0064] As described above, it is not necessary to sandwich a sealing rubber part between the base part 87 and the cover part 88 because the sealing between them can be ensured only by the base part 87 and the cover part 88. However, a sealing rubber member may be sandwiched between the base part 87 and the cover part 88 to further improve the sealing.

[0065] 2, an oil strainer 72 that sucks up oil stored in the case 90 is disposed at the bottom of the case 90, between the gear power transmission mechanism 50 and the chain power transmission mechanism 80. The oil strainer 72 is in communication with the oil pump 70, and the oil sucked up by the oil strainer 72 is supplied to the oil pump 70 and further from the oil pump 70 to the control valve unit 95.

[0066] The control valve unit 95 is attached to the front side of the vehicle 100 in the case 90 (the right side in FIG. 2). Oil is supplied to the control valve unit 95 from the oil pump 70, and the control valve unit 95 is composed of a solenoid valve, a spool valve, etc., and controls the oil pressure supplied to the oil chamber of the primary pulley 21, the oil chamber of the secondary pulley 22, the forward / reverse switching mechanism 30, the lock-up clutch 41, etc.

[0067] A fourth gear 54 of the gear power transmission mechanism 50 is fixed to the differential gear device 60. A first gear 51, a second gear 52, and a third gear 53 are arranged above the differential gear device 60. The secondary pulley 22 is located to the left of the vehicle 100 (the farther side of the paper surface) than the first gear 51, and is not shown in FIG. 2. The fourth gear 54 is arranged such that a part of it is immersed in the oil stored in the case 90.

[0068] Next, the main functions and effects of the power transmission device 10 configured as above will be described.

[0069] (1) In the power transmission device 10 of this embodiment, the space in the case 90 in which the oil is stored is partitioned by the baffle plate 86 into a first space R1 in which the driven sprocket 83 provided on the input shaft 71 of the oil pump 70 is positioned, and a second space R2 in which the oil strainer 72 communicating with the oil pump 70 is positioned, and at least a portion of the driven sprocket 83 is immersed in oil in the first space R1.

[0070] The baffle plate 86 is also composed of a base portion 87 and a cover portion 88 that is connected to the base portion 87 and covers the driven sprocket 83 .

[0071] In addition, the base portion 87 and the cover portion 88 are engaged with each other by a clip 88c which serves as an engaging piece extending from one and engaging with the outer surface of the other, and are fastened to each other by a bolt 89 at a position different from the engagement position of the clip 88c.

[0072] As a result, only one bolt is required to connect the base portion 87 and the cover portion 88, so that the base portion 87 and the cover portion 88 can be connected even if it is difficult to secure space for bolting due to other parts arranged around the baffle plate 86.

[0073] (2) Furthermore, the clip 88c has a spring force, which presses the base portion 87 and the cover portion 88 against each other, ensuring a seal between them.

[0074] This eliminates the need for sealing parts to ensure sealing between the base portion 87 and the cover portion 88, making it possible to reduce the number of steps and costs required for assembling the baffle plate 86.

[0075] When the base portion 87 and the cover portion 88 are joined, they come into direct contact with each other. However, the pressing force between the base portion 87 and the cover portion 88 is appropriately adjusted by the elastic deformation of the clip 88c, so that it is possible to prevent excessive force from acting on the base portion 87 and the cover portion 88, causing plastic deformation of these parts.

[0076] (3) The base portion 87 is disposed between the case 90 and the driven sprocket 83, and the clip 88c is provided on the cover portion 88.

[0077] When the clip 88c is provided on the cover portion 88, the clip 88c is engaged from the outside of the base portion 87, so that the clip 88c does not interfere with the driven sprocket 83 and the chain 84 arranged on the inside of the base portion 87, improving the workability of connecting the base portion 87 and the cover portion 88.

[0078] The clip 88c may be provided on the base portion 87. In this case, the clip 88c extends from the base portion 87 and engages with the outer surface of the cover portion 88 (the surface of the cover portion 88 or the cover plate 88a opposite the case 90). If a gap large enough to insert the clip 88c cannot be secured between the base portion 87 and the case 90, it is preferable to provide the clip 88c on the base portion 87.

[0079] An embodiment of the present invention has been described above, but the above embodiment merely illustrates one application example of the present invention, and is not intended to limit the technical scope of the present invention to the specific configuration of the above embodiment.

[0080] For example, in the above embodiment, the power transmission device 10 is a belt-type continuously variable transmission. However, the power transmission device 10 may be a reduction gear with a fixed gear ratio, a stepped transmission using planetary gears, or the like. [Explanation of symbols]

[0081] 10 Power transmission device 70 Oil pump 71 Input shaft 80 Chain power transmission mechanism 83 Driven sprocket 86 Baffle plate 87 Base 88 Cover part 88c Clip (engagement piece) 90 cases

Claims

1. A power transmission device, wherein a space in a case in which oil is stored is partitioned by a baffle plate into a first space in which a driven sprocket provided on an input shaft of an oil pump is disposed and a second space in which an oil strainer communicating with the oil pump is disposed, and at least a portion of the driven sprocket is immersed in oil in the first space, The baffle plate includes a base portion and a cover portion that is connected to the base portion and covers the driven sprocket. The base portion and the cover portion are engaged with each other by an engagement piece extending from one of them and engaging with an outer surface of the other of them, and are connected to each other by a bolt at a position different from the engagement position of the engagement piece. Power transmission device.

2. 2. The power transmission device according to claim 1, The engaging piece is a clip having a spring force, and the spring force presses the base part and the cover part against each other. Power transmission device.

3. 3. The power transmission device according to claim 1 or 2, the base portion is disposed between the case and the driven sprocket, The engagement piece is provided on the cover portion. Power transmission device.

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