Gearbox

Abstract

[Problem] To prevent oil spattered up by a gear power transmission mechanism from splashing on a chain power transmission mechanism. [Solution] A speed change device comprises: a case storing oil; a gear power transmission mechanism that is supported in the case, and operates in a state in which the gear power transmission mechanism is partly immersed in the oil stored in the case; a chain power transmission mechanism supported in the case; and a speed change mechanism supported in the case. The case has a rib that covers the chain power transmission mechanism on the upper side in the vertical direction of the chain power transmission mechanism. The rib has an oil passage therein for supplying the oil to the speed change mechanism.

Description

[Technical field]

[0001] The present invention relates to a transmission. [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, thereby lubricating the drive sprocket, driven sprocket, and chain.

[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] However, in the above structure, the drive sprocket and chain that drive the driven sprocket are not covered by a baffle plate, so the oil stirred up by the gear power transmission mechanism consisting of the final gear etc. may splash onto the drive sprocket and chain and break into smaller droplets, increasing the amount of air contained in the oil.

[0006] The present invention has been made in consideration of these technical problems, and has an object to prevent oil stirred up by the gear power transmission mechanism from getting onto the chain power transmission mechanism. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided a transmission comprising a case for storing oil, a gear power transmission mechanism supported by the case and operating with a portion of it immersed in the oil stored in the case, a chain power transmission mechanism supported by the case, and a shift mechanism supported by the case, wherein the case has a rib covering the chain power transmission mechanism vertically above the chain power transmission mechanism, and the rib has an oil passage therein for supplying oil to the shift mechanism. Effect of the Invention

[0008] According to the above aspect, the rib functions as a partition wall separating the gear power transmission mechanism and the chain power transmission mechanism, and prevents the oil stirred up by the gear power transmission mechanism from splashing onto the chain power transmission mechanism. This prevents the oil splashed onto the chain power transmission mechanism from becoming even smaller droplets, and prevents the air contained in the oil from increasing. In addition, the rib has multiple functions as a partition wall and an oil passage, making it possible to effectively use the limited space within the transmission. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram for explaining the general configuration of a vehicle equipped with a transmission according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a view of the inside of the transmission seen from the cover side. [Diagram 3] FIG. 3 is a view of the case cover as seen from the inside. [Figure 4] FIG. 4 is a partially enlarged perspective view of the rib. [Diagram 5] FIG. 5 is a cross-sectional view taken along line VV of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a vehicle 100 equipped with a transmission 10 according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0011] Fig. 1 is a schematic diagram for explaining the general configuration of a vehicle 100. As shown in Fig. 1, the vehicle 100 includes an engine 1 and a transmission 10 provided in a power transmission path connecting the engine 1 and drive wheels 9.

[0012] The transmission 10 is a belt-type continuously variable transmission including 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 attached to the opening of the case 90.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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 .

[0022] 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.

[0023] 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.

[0024] 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.

[0025] The case 90 includes an intermediate wall 91 and an intermediate cover 92 attached to an opening of the intermediate wall 91 (see 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.

[0026] 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 .

[0027] 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.

[0028] 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.

[0029] 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.

[0030] Next, the internal configuration of the transmission 10 will be described in detail with reference to FIGS.

[0031] 2 is a view of the inside of the transmission 10 as seen 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 forward 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). Moreover, 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.

[0032] As shown in FIG. 2, on the rear side of the vehicle 100 in the transmission 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.

[0033] A chain power transmission mechanism 80 is supported by a case 90 on the front side of the vehicle 100 in the transmission 10 .

[0034] The forward / reverse switching mechanism 30 and the primary pulley 21 are located to the left of the drive sprocket 82 of the chain power transmission mechanism 80 on the vehicle 100 (to the rear of the drawing).

[0035] The intermediate cover 92 is secured to the intermediate wall 91 by a number of bolts 94 .

[0036] A drive sprocket 82 is rotatably supported on intermediate cover 92 via a bush 81. A driven sprocket 83 is disposed below drive sprocket 82. Drive sprocket 82 and driven sprocket 83 are connected by a chain 84. The rotation directions of drive sprocket 82 and driven sprocket 83 are both clockwise in FIG. 2.

[0037] The driven sprocket 83 is covered on both sides and on its vertically lower side by a baffle plate 86. The space in the case 90 where the oil is stored is divided into a space in which the driven sprocket 83 is disposed and a space in which an oil strainer 72 that communicates with an oil pump 70 (described below) is disposed. By separating the space in which the driven sprocket 83 is disposed in this way, air in the oil that increases when the driven sprocket 83 and chain 84 stir the oil stored in the case 90 is prevented from being sucked into the oil strainer 72.

[0038] The oil pump 70 is located to the left of the vehicle 100 (to the rear of the paper surface) relative to the driven sprocket 83, and is not shown in FIG.

[0039] 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.

[0040] 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.

[0041] 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 disposed above the differential gear device 60. The rotation directions of the first gear 51, the second gear 52, the third gear 53, and the fourth gear 54 are clockwise, counterclockwise, counterclockwise, and clockwise, respectively, in FIG. 2.

[0042] The secondary pulley 22 is located to the left of the vehicle 100 (to the rear of the page) relative to the first gear 51, and is indicated by a dashed line in FIG.

[0043] The fourth gear 54 is disposed so that a part of it is immersed in the oil stored in the case 90. That is, the gear power transmission mechanism 50 operates with a part of it immersed in the oil. As a result, when the gear power transmission mechanism 50 operates, the oil is scooped up by the gear power transmission mechanism 50.

[0044] FIG. 3 is a view of the case cover 93 as seen from the inside.

[0045] The case cover 93 has a flange 93a, a through hole 93b, and a through hole 93c.

[0046] The case cover 93 is fixed to the case 90 with a plurality of bolts (not shown) by arranging the flange 93a opposite the flange 91a (see FIG. 2) of the case 90.

[0047] With the case cover 93 fixed to the case 90, the output shaft 43 of the torque converter 40 is inserted through the through hole 93b. The output shaft (not shown) of the differential gear unit 60 is inserted through the through hole 93c. The periphery of the through hole 93b is disposed opposite to the intermediate cover 92.

[0048] Here, when the gear power transmission mechanism 50 operates, the oil stirred up by the gear power transmission mechanism 50 splashes toward the chain power transmission mechanism 80 as shown by the white arrow in FIG.

[0049] If the scattered oil gets on the chain power transmission mechanism 80, the oil will break down into smaller droplets, increasing the amount of air contained in the oil, which may cause noise when the oil pump 70 sucks in the oil and may affect the durability of the oil pump 70. Furthermore, the increased amount of air contained in the oil may increase the driving resistance of the drive sprocket 82, etc.

[0050] Therefore, in the transmission 10 of this embodiment, a rib 96 is provided that protrudes from the surface of the case 90, or more specifically, the intermediate cover 92, and extends in the front-to-rear direction of the vehicle (left-to-right direction in FIG. 2). The rib 96 functions as a partition that separates the gear power transmission mechanism 50 and the chain power transmission mechanism 80, thereby preventing oil stirred up by the gear power transmission mechanism 50 from splashing on the chain power transmission mechanism 80.

[0051] The structure of the rib 96 will now be described in detail.

[0052] 2, the rib 96 is disposed at a position vertically above the chain power transmission mechanism 80, and has a total length longer than the diameter of the drive sprocket 82. In this way, the chain power transmission mechanism 80 is covered by the rib 96.

[0053] Furthermore, the rib 96 is disposed between the secondary pulley 22 and the control valve unit 95. An oil passage 96d is formed inside the rib 96, through which oil is supplied from the control valve unit 95 to the secondary pulley 22 of the variator 20. The oil passage 96d is connected to an oil passage (not shown) in the intermediate cover 92, and further to an oil passage 90a in the case 90, thereby providing communication between the secondary pulley 22 and the control valve unit 95.

[0054] This allows the rib 96 to have multiple functions as a partition and an oil passage, making effective use of the limited space within the transmission 10. Also, the length of the oil passage between the secondary pulley 22 and the control valve unit 95 can be shortened, simplifying the oil passage structure within the transmission 10. Also, since the provision of the oil passage 96d makes the rib 96 hollow, it is possible to suppress an increase in weight compared to the case where a solid rib is provided.

[0055] The rib 96 is bent at a bent portion 96c located approximately in the center in the longitudinal direction to form a shape that is convex upward in the vertical direction, and is composed of a first straight portion 96a and a second straight portion 96b on either side of the bent portion 96c.

[0056] By configuring the rib 96 with the first straight portion 96a and the second straight portion 96b, the oil passages in the rib 96 can be easily formed by drilling. Specifically, first, the rib 96 is formed integrally when the intermediate cover 92 is cast. At this time, the rib 96 is solid. Next, oil passages are formed in the straight portions 96a, 96b from both ends by drilling, and these are connected at the bent portion 96c. Finally, the openings at both ends of the rib 96 are sealed with plugs, respectively, and the oil passages in the rib 96 can be formed.

[0057] Although the rib 96 can be provided on the intermediate wall 91 instead of the intermediate cover 92, providing the rib 96 on the intermediate cover 92 as in this embodiment makes it easier to process the oil passage 96d.

[0058] Furthermore, because the ribs 96 have a shape that convex vertically upward, the inclination allows the oil on the ribs 96 to flow efficiently to both sides of the ribs 96 in the longitudinal direction, reducing the amount of oil that reaches the chain power transmission mechanism 80. Furthermore, the longer the overall length of the ribs 96, the more advantageous it is to reduce the amount of oil that reaches the chain power transmission mechanism 80; however, by bending the ribs 96, it is also possible to arrange long ribs 96 in the limited space around the drive sprocket 82.

[0059] The shape of the rib 96 is not limited to this, and may be a straight shape without the bent portion 96c. This makes it easier to form the oil passage inside the rib 96. The rib 96 may also be partially or completely curved. If the rib 96 is curved, it is not possible to form the internal oil passage by drilling, but the oil passage can be formed inside the rib 96 by casting a previously curved pipe together with the intermediate cover 92 when casting it.

[0060] Fig. 4 is a perspective view of a part of the rib 96 as viewed from the direction of the arrow IV in Fig. 2. Fig. 5 shows a schematic cross section taken along the line VV in Fig. 2.

[0061] A plurality of oil passages 92a to 92d are formed in the surface of the intermediate cover 92, and among them, the oil passages 92a and 92b intersect with the rib 96. The oil passages 92a and 92b that intersect with the rib 96 pass through the base end (root) side of the rib 96, and are disposed apart in the height direction of the rib 96 from the oil passage 96d that passes through the rib 96 at the intersecting portion. In other words, the oil passage 96d does not communicate with the oil passages 92a and 92b. This allows the plurality of oil passages to be disposed efficiently in the limited space on the intermediate cover 92.

[0062] 5, the height H of the rib 96 is approximately equal to the distance D between the case 90 (middle cover 92) and the case cover 93 at the portion where the rib 96 is provided. This reduces the gap between the rib 96 and the case cover 93.

[0063] The oil stirred up by the gear power transmission mechanism 50 hits the left side of the rib 96 in Figure 5, so by reducing the gap between the rib 96 and the case cover 93, the amount of oil that passes over the rib 96 and reaches the chain power transmission mechanism 80 can be reduced.

[0064] In addition, the cross section of the rib 96 is rectangular. This makes the vertical upper surface of the rib 96 (the surface on the left side in FIG. 5 ) flat, and allows oil that splashes from the gear power transmission mechanism 50 and hits the rib to flow efficiently to both sides in the longitudinal direction of the rib 96. This also makes it possible to reduce the amount of oil that passes over the rib 96 and reaches the chain power transmission mechanism 80.

[0065] In addition, because the surface of the rib 96 facing the case cover 93 is flat, the vertical length (horizontal length in FIG. 5) of the gap between the rib 96 and the case cover 93 is increased. This makes it more difficult for oil to pass through the gap between the rib 96 and the case cover 93, and the amount of oil that passes over the rib 96 and reaches the chain power transmission mechanism 80 can be reduced.

[0066] When the chain power transmission mechanism 80 is operated, oil is also kicked up by the chain power transmission mechanism 80. However, the presence of the rib 96 reduces the amount of oil that reaches the gear power transmission mechanism 50, thereby preventing an increase in air contained in the oil due to the oil kicked up by the chain power transmission mechanism 80.

[0067] The main functions and effects of the transmission 10 configured as above will now be described.

[0068] (1) The transmission 10 of this embodiment includes a case 90 that stores oil, a gear power transmission mechanism 50 that is supported by the case 90 and operates with a portion of it immersed in the oil stored in the case 90, a chain power transmission mechanism 80 supported by the case 90, and a variator 20 supported by the case 90.

[0069] The case 90 includes a rib 96 that covers the chain power transmission mechanism 80 on the vertically upper side of the chain power transmission mechanism 80. The rib 96 includes an oil passage 96d therein that supplies oil to the variator 20.

[0070] By providing the rib 96 covering the chain power transmission mechanism 80, the rib 96 functions as a partition that separates the gear power transmission mechanism 50 and the chain power transmission mechanism 80, and can prevent the oil stirred up by the gear power transmission mechanism 50 from splashing onto the chain power transmission mechanism 80. This prevents the oil from splashing onto the chain power transmission mechanism 80 and becoming even smaller droplets, and can prevent the amount of air contained in the oil from increasing.

[0071] Furthermore, by providing the rib 96 with the oil passage 96d therein for supplying oil to the variator 20, the rib 96 can function as an oil passage in addition to functioning as a partition, thereby making more effective use of the limited space within the transmission 10 compared to a case in which each function is realized by a separate member. Also, because the rib 96 is hollow, the weight increase due to the provision of the rib 96 can be suppressed.

[0072] (2) Moreover, the transmission 10 is a belt-type continuously variable transmission having a secondary pulley 22 that operates according to the oil pressure of the oil supplied to the oil chamber, and a control valve unit 95 that controls the oil pressure of the oil supplied to the oil chamber. The rib 96 is disposed between the secondary pulley 22 and the control valve unit 95, and an oil passage 96d in the rib 96 is an oil passage that supplies oil from the control valve unit 95 to the oil chamber of the secondary pulley 22.

[0073] According to this configuration, the length of the oil passage between the secondary pulley 22 and the control valve unit 95 can be shortened, and the oil passage structure within the transmission 10 can be simplified.

[0074] (3) Additionally, the case 90 includes oil passages 92a, 92b in addition to the oil passage 96d. The oil passages 92a, 92b pass through the base end side of the rib 96 and are separated from the oil passage 96d in the rib 96 in the height direction of the rib 96 (FIGS. 4 and 5). In this manner, by utilizing the rib 96 to arrange the multiple oil passages 96d, 92a, 92b three-dimensionally, the multiple oil passages can be efficiently arranged in the limited space on the intermediate cover 92.

[0075] (4) Furthermore, a case cover 93 is provided that is fixed to the case 90 and covers the gear power transmission mechanism 50 and the chain power transmission mechanism 80, and the height H of the rib 96 is set to be approximately equal to the distance D between the case 90 (middle cover 92) and the case cover 93 at the location where the rib 96 is provided. This reduces the gap between the rib 96 and the case cover 93, further reducing the amount of oil that passes over the rib 96 and reaches the chain power transmission mechanism 80.

[0076] 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.

[0077] For example, in the above embodiment, the transmission 10 is a belt-type continuously variable transmission. However, the transmission 10 may be a reduction gear with a fixed gear ratio, a stepped transmission using planetary gears, or the like. [Explanation of symbols]

[0078] 10. Gearbox 20 Variator 22 Secondary pulley 50 Gear power transmission mechanism 80 Chain power transmission mechanism 90 cases 92 Middle cover 92a Oil Channel (another oil channel) 92b Oil Channel (another oil channel) 93 Case Cover 95 Control valve unit 96 Ribs 96d Oil road

Claims

1. A transmission including a case for storing oil, a gear power transmission mechanism supported by the case and operable with a portion of the gear power transmission mechanism immersed in the oil stored in the case, a chain power transmission mechanism supported by the case, and a speed change mechanism supported by the case, the case includes a rib that covers the chain power transmission mechanism on a vertically upper side of the chain power transmission mechanism, The rib has an oil passage therein for supplying oil to the speed change mechanism. Transmission.

2. 2. The transmission according to claim 1, the transmission is a belt-type continuously variable transmission having a pulley that operates in response to the oil pressure of oil supplied to an oil chamber, and a control valve unit that controls the oil pressure of the oil supplied to the oil chamber, the rib is disposed between the pulley and the control valve unit, The oil passage in the rib is an oil passage for supplying oil from the control valve unit to the oil chamber of the pulley. Transmission.

3. 3. The transmission according to claim 1 or 2, The case includes an oil passage separate from the oil passage, The other oil passage passes through a base end side of the rib and is separated from the oil passage in the rib in a height direction of the rib. Transmission.

4. 3. The transmission according to claim 1 or 2, a case cover fixed to the case and covering the gear power transmission mechanism and the chain power transmission mechanism, The height of the rib is approximately equal to the distance between the case and the case cover at a portion where the rib is provided. Transmission.

Images