FR3083586A1 - VEHICLE TRANSMISSION - Google Patents

Abstract

A transmission for a vehicle includes a transmission housing. The transmission case has a bottom wall that includes a first bulge portion (121) that bulges upward from the bottom wall and a second bulge portion (122) that bulges upward from the bottom wall and is located closer to the final driven gear than the first bulge. A suction port (112a) of an oil strainer (112) is disposed between the first bulge part and the second bulge part and is also located under the upper ends (121a, 122a) of the first bulge part and the the second part bulges. This can enhance the suction efficiency of an oil pump through a simple structure. Abstract Figure: Figure 9

Description

Description

Title of the invention: TRANSMISSION FOR VEHICLE

Technical Field [0001] The present invention relates generally to a transmission for a vehicle.

PRIOR ART [0002] As a general rule, transmissions mounted on vehicles are equipped with a strainer which filters the lubricating oil. The first publication of Japanese patent No. 2015-137694 discloses a transmission equipped with an oil strainer.

The above transmission is equipped with a housing in which a vehicle transmission is mounted, an oil tank in which the lubricating oil of the housing accumulates, a strainer with an orifice hydraulic oil intake which communicates with an oil pump and gives on the oil tank, a return oil circuit through which the hydraulic oil is collected and returned to the oil tank, and an outlet orifice through which the hydraulic oil is discharged from the return oil circuit to the oil tank.

The transmission is also equipped with a line through which the hydraulic oil is directed from the outlet to an oil inlet of the strainer. The line has an inlet which opens onto the transmission outlet and an outlet which opens near the oil inlet of the strainer located under the surface of the hydraulic oil inside the tank d 'oil.

This prevents the air from mixing with the hydraulic oil drawn into the strainer and guarantees the stability of the collection of hydraulic oil supplied in order to lubricate the transmission or hydraulic oil sprayed by rotation of the parts of the transmission. .

The aforementioned type of transmission requires driving in order to bring the hydraulic oil from the outlet to the oil intake of the strainer, which increases the number of parts of the transmission, and also requires space to install the pipe. As a result, the structure of the transmission is complex.

The present invention has been designed to meet the problems described above. The invention relates to a vehicle transmission with a simple structure capable of enhancing the efficiency of an oil pump in terms of oil suction.

Summary of the Invention According to one aspect of the invention, a vehicle transmission includes: (a) a transmission case which has a bottom wall on which oil is accumulated; (b) an output shaft which is retained by the transmission housing so as to be able to rotate and equipped with a rotary element projecting the oil upwards; and (c) an oil strainer which extends in an axial direction from the output shaft inside the transmission case and is actuated by an oil pump to suck up the oil, accumulated on the lower wall, via a suction opening. The bottom wall includes a first swollen portion and a second swollen portion. The first swollen portion is swollen upward from the bottom wall. The second swollen portion is swollen upward from the bottom wall and is located closer to the rotary member than the first swollen portion. The oil strainer suction port is disposed between the first swollen portion and the second swollen portion and is also located under the upper ends of the first swollen portion and the second swollen portion.

According to one embodiment, the bottom wall comprises a projecting wall which projects upwards from the bottom wall and extends in the same direction in which the oil strainer extends, the projecting wall being disposed between the oil strainer and the rotary element and placed so as to overlap the suction port in the axial direction of the output shaft.

According to one embodiment, the lower wall comprises a curved wall which faces the rotary element and projects upwards from the lower wall in a direction of rotation of the rotary element. Part of the curved wall is located below an upper projecting end of the curved wall and is connected to an upper end of the projecting wall, and the curved wall has an opening which communicates between the space in which the rotary member is disposed and the space in which the oil strainer is disposed.

According to one embodiment, the vehicle transmission further comprises a first rotation shaft, a second rotation shaft and a third rotation shaft, the first rotation shaft being located on an upper side of the transmission housing and equipped with a first gear, the second rotation shaft being located below the first rotation shaft and equipped with a second gear, the third rotation shaft being located below the first rotation shaft and the second rotation shaft and fitted with a third gear; the transmission housing comprising (a) a guide wall which extends in the direction in which the oil strainer extends, which has one end to which the curved wall leads and which is connected to the upper end of the projecting wall, (b) a first curved wall which extends upwards from the guide wall so as to make fa this at the third gear and which has an upper end part comprising a first upper end and a second upper end, the second upper end being located next to the first upper end in the axial direction of the output shaft and above the first upper end, (c) a second curved wall which extends upwards from the first upper end and faces the second gear, and (d) a third curved wall which extends upwards from the second upper end and faces the third gear; and the guide wall protruding from the first curved wall towards the oil screen.

According to one embodiment, the oil strainer is arranged so that one of its parts is located under the guide wall.

According to one embodiment, the guide wall, the projecting wall and the second bulged part are designed so as to follow the outer periphery of the oil strainer.

Advantages provided The above-mentioned invention makes it possible to reinforce the suction efficiency of the oil pump with a simple structure.

Brief description of the drawings

Fig.l [fig.l] is a rear view of a vehicle transmission according to an embodiment of the invention;

Fig. 2 [fig-2] is a structural view of a vehicle transmission according to an embodiment of the invention;

Fig. 3 [fig.3] is a left side view of a transmission housing on which is omitted a transmission cover according to an embodiment of the invention;

Fig. 4 [fig-4] is a right side view of a transmission housing on which is omitted a torque converter box according to an embodiment of the invention;

Fig. 5 [fig.5] is a right side view of a transmission housing according to an embodiment of the invention;

Fig. 6 [Fig.6] is an oblique perspective sectional view of a transmission case taken along the axis VII-VII of the Lig. 3;

Fig. 7 [fig-7] is a sectional view of a transmission case taken along the axis VII-VII of the Lig. 3;

Fig. 8 [fig.8] is a sectional view taken along axis VIII-VIII of the Lig. 1;

Fig. 9 [Fig-9] is an enlarged view which shows a region around a strainer of a vehicle transmission, seen from the right side, according to an embodiment of the invention.

Description of the embodiments A transmission for a vehicle according to an embodiment of the invention comprises: (a) a transmission casing which has a bottom wall on which oil is accumulated; (b) an output shaft which is retained by the transmission housing so as to be able to rotate and equipped with a rotary element projecting the oil upwards; and (c) an oil strainer which extends in an axial direction from the output shaft inside the transmission case and is actuated by an oil pump to suck up the oil, accumulated on the lower wall, via a suction opening. The bottom wall includes a first swollen portion and a second swollen portion. The first swollen portion is swollen upward from the bottom wall. The second swollen portion is swollen upward from the bottom wall and is located closer to the rotary member than the first swollen portion. The oil strainer suction port is disposed between the first swollen portion and the second swollen portion and is also located under the upper ends of the first swollen portion and the second swollen portion. This improves the suction efficiency of the oil pump with a simplified structure.

Embodiment [0025] A vehicle transmission according to an embodiment of the invention will be described below with reference to the drawings. Figs. 1 to 9 show the vehicle transmission according to the embodiment of the invention. In Figs. 1 to 9, a vertical direction, a longitudinal direction and a lateral direction are based on a transmission mounted in the vehicle. A direction perpendicular to the longitudinal direction is the lateral direction. A direction in height of the transmission is the vertical direction.

First, the structure will be described. In Fig. 1, a vehicle transmission (which will be simply referred to as the transmission 1) mounted in a vehicle, such as an automobile, comprises the transmission casing 90. The transmission casing 90 comprises the torque converter box 91, the casing 92 and the clutch housing 93.

On a right end of the torque converter box 91, is arranged the flange 91R to which the motor 2 is connected. On the left end of the torque converter box 91, the flange 9IL is also arranged.

On a right end of the transmission housing 92, is arranged the flange 92R. The flange 9IL of the torque converter box 91 is connected to the flange 92R using bolts 90A.

In FIG. 2, the partition wall 94 isolates the torque converter chamber 91A and the gear chamber 92A from each other inside the transmission casing 90. The torque converter chamber 91A is defined by l space in the torque converter box 91. The torque converter 4 is arranged in the torque converter chamber 91 A.

The gear chamber 92A is defined by the space located in the transmission casing 92. The constant-gear gear mechanism 77 implemented by a gearbox with a parallel shaft is arranged in the chamber 92A. Transmission 1 in this embodiment is equipped with 7 forward gears and a reverse gear.

The gear mechanism 77 includes the input shaft 5, the front idle shaft 6, the rear idle shaft 7, the intermediate shaft 8, the output shaft 9 and the shaft reverse gear 10 (see Fig. 3). The engine 2 is designed as a transverse engine whose crankshaft 3 extends in the direction of the width of the vehicle.

The torque converter 4 includes the front cover 4A connected to the crankshaft 3 via the drive plate 4A and the shell 4C connected to the front cover 4B. The torque converter 4 functions as a hydraulic coupling in order to transmit the power between the engine 2 and the transmission 1.

The shell 4C 10B connected to the crankshaft 3 has a pump rotor, which is not shown, fixed on its internal surface. Inside the shell 4C is arranged a turbine wheel, which is not shown, facing the pump rotor. The turbine wheel is connected to the input shaft 5. A stator, which is not shown, is arranged between the pump rotor and the turbine wheel.

The rotation of the crankshaft 3 causes the rotation of the front cover 4B, the shell 4C and the pump rotor of the torque converter 4 via the drive plate 4A. Thus, centrifugal forces act on the pump rotor, creating a flow of liquid flowing from the pump rotor to the turbine wheel in the torque converter 4.

The flow of liquid rotates the turbine wheel so that the input shaft 5 connected to the turbine wheel rotates. The stator operates so as to direct the flow of liquid from the turbine wheel in a direction of rotation of the pump rotor, thereby amplifying the power supplied by the motor 2.

The input shaft 5 comprises the main input shaft 11 which has an oil circuit extending in its axial center and the hollow secondary input shaft 12 which is arranged at the outer periphery of the main input shaft 11 and extends coaxially with respect to the main input shaft 11. The main input shaft 11 is located inside the secondary input shaft 12 so that it can rotate around it via a needle bearing.

The torque converter 4 is connected to the end 1a of the main input shaft 11. The power generated by the motor 2 is transmitted to the main input shaft 11 via the torque converter 4 .

The gear mechanism 77 is equipped with the planetary gear train 21. The planetary gear train 21 is mounted on the outer peripheries of the main input shaft 11 and the secondary input shaft 12 so as to be coaxial with respect to the main input shaft 11. The planetary gear train 21 is located closer to the motor 2 than the secondary input shaft 12.

The planetary gear train 21 connects the main input shaft 11 and the end 12a of the secondary input shaft 12 and has the function of reducing the speed of rotation of the input shaft 11 and transmit the torque from the main input shaft 11 to the secondary input shaft 12. More specifically, the planetary gear train 21 is equipped with the support 22, the sun gear 23 and the ring gear 24 .

The support 22 retains the satellite pinions 22A so as to be able to rotate around their axes and also around the main input shaft 11. The sun gear 23 integrates with the satellite pinions 22A and is switched by the device braking 31, as described in more detail below, between a locked state in which the sun gear 23 is prevented from turning and an unlocked state in which the sun gear 23 is allowed to turn.

The crown 24 is connected to the main input shaft 11 via splines so as to be able to rotate around the main input shaft 11. The crown 24 integrates with the planet gears 22A so that the power is transmitted from the crown 24 to the support 22.

The one-way clutch 25 is disposed between the support 22 and the end 22a of the secondary input shaft 12. The one-way clutch 25 has the function of transmitting the power of the support 22 to the shaft of secondary input 12 in order to increase the speed of the secondary input shaft 12, while blocking the power transmission which increases the speed of the support 22 from the secondary input shaft 12 to the support 22.

Therefore, the one-way clutch 25 establishes the power transmission from the main input shaft 11 to the secondary input shaft 12, but blocks the power transmission from the secondary input shaft 12 to the main input shaft 11.

The gear mechanism 77 is equipped with the braking device 31. The braking device 31 is disposed outside the outer periphery of the main input shaft 11 in a radial direction from the main input shaft 11 so as to be coaxial with respect to the main input shaft 11. The braking device 31 is equipped with the cylindrical braking box 32. The braking box 32 is fixed to the partition wall 94 of the converter box of torque 91. The brake box 32 protrudes from the partition wall 94 towards the planetary gear train 21.

The brake housing 32 has friction plates 34 and 35 and the cylindrical clutch hub 36 is disposed there. The clutch hub 36 is formed integrally with the sun gear 23. The clutch hub 36 extends from the sun gear 23 to the brake housing 32. In this embodiment, the clutch hub 36 constitutes part of the sun gear 23. The sun gear 23 is partially disposed in the brake box 32.

The friction plate 34 is connected via grooves to the outer periphery of the clutch hub 36 so as to rotate around the clutch hub 36. The friction plate 34 can move in an axial direction of the main input shaft 11.

The friction plates 35 are connected via grooves to the inner periphery of the brake housing 32 and are prevented from rotating around the brake housing 32 in the direction in which the main input shaft 11 rotates, but they can move in the axial direction of the main input shaft 11. The friction plates 34 and 35 are arranged alternately in the axial direction of the main input shaft 11.

During operation of the braking device 31, when one of the friction plates 35 which is located closer to the torque converter 4 is pushed by the pistons 37, the friction plate 34 and the friction plate 35 enter in frictional contact with each other to securely attach the sun gear 23 to the brake housing 32. This prevents the sun gear 23 from rotating. When subjected to oil pressure, the pistons 37 are moved so as to push the friction plate 35 towards the planetary gear train 21.

When the sun gear 23 is prevented from rotating, the power is transmitted from the main input shaft 11 to the support 22 via the ring 24. Thus, the support 22 rotates so that the power is transmitted from the support 22 to the secondary input shaft 12 via the one-way clutch 25.

The planetary gear train 21 is capable of variably adjusting a speed ratio between the planet gears 22A, the sun gear 23 and the ring gear 24 in order to reduce and transmit the speed of the main input shaft 11 to the secondary input shaft 12. Consequently, the planetary gear train 21 acts as a speed reducer.

During operation of the braking device 31, when the hydraulic pressure disappears from the pistons 37, the friction plates 35 are displaced by the pressure exerted by a return spring, which is not shown, away from the friction plate 34.

This allows the sun gear 23 to rotate. Thus, the planet gears 22A pivot so that the support 22 stops rotating. As a result, no power is transmitted via a power transmission circuit from the main input shaft 11 to the secondary input shaft 12 via the planetary gear train 21.

The clutch 41 is disposed on the end 11b of the main input shaft 11 and the end 12b of the secondary input shaft 12. The clutch 41 is disposed inside the casing clutch 93.

The clutch 41 includes the clutch drum 42 and the clutch hub 43. The clutch drum 42 is connected via splines to the main input shaft 11 so that they rotate together. The clutch hub 43 is connected via splines to the secondary input shaft 12 so that they rotate together.

Annular friction plates 44 are mounted on the clutch drum

42. The friction plates 44 rotate together with the clutch drum 42 and can move in the axial direction of the main input shaft IL [0056] A plurality of friction plates 45 are mounted on the hub. clutch

43. The friction plates 44 and the friction plates 45 are arranged alternately in the axial direction of the main input shaft IL [0057] During the operation of the clutch 41, when the friction plates 44 and the friction plates 45 come into friction contact with each other, the clutch drum 42 and the clutch hub 43 rotate together to transmit the power, generated by the motor 2, from the main input shaft 11 to the secondary input shaft 12.

When the friction plates 44 and the friction plates 45 disengage from each other, the power, generated by the motor 2, is not transmitted from the main input shaft 11 to the shaft d secondary input 12.

4th gear 51, 5th gear 52, the input idle gear 53 and the synchronizer 54 are arranged between the torque converter 4 and the clutch 41 in the axial direction of the input shaft secondary 12.

4th gear 51 and 5th gear 52 are retained by the secondary input shaft 12 so that they can rotate relative to each other. The input idle gear 53 rotates around the secondary input shaft 12.

When a 4th gear or a 5th gear is selected during a gear change, the synchronizer 54 is moved by a gear shift fork, which is not shown, from neutral to the 4th gear 51 or 5th gear 52.

For example, in the event of an automatic gear change, the synchronizer 54 is moved by an actuator, which is not shown. When a gear lever is actuated by the driver of a vehicle on one of the speeds of the transmission 1, the actuator operates the synchronizer 54 and the synchronizers 68 and 69, which will be described below, in order to order the gear ratios in transmission 1 using a shift card which lists parameters such as the accelerator position and vehicle speed.

When the gear lever is moved to a reverse position, the actuator operates the synchronizer 88 as described below in more detail. Synchronizers 54, 68, 69 and 88 are implemented by known synchronizers using synchronization rings, more detailed explanations being omitted herein.

When the synchronizer 54 is moved from neutral to 4th gear 51, 4th gear engages with synchronizer 54, thus joining the secondary input shaft 12 and 4th gear 51 via synchronizer 54, from so that 4th gear 51 rotates with the secondary input shaft 12.

When the synchronizer 54 is moved from neutral to 5th gear 52, the 5th gear engages with the synchronizer 54, thus joining the secondary input shaft 12 and the 5th gear 52 via the synchronizer 54, so that the 5th gear 52 rotates with the secondary input shaft 12.

The idle gear 61 and the idle gear 62 are mounted on the front idle shaft 6, the idle gear 62 having a diameter smaller than that of the idle gear 61. The gears of idle 61 and 62 rotate around the front idle shaft 6. The idle gear 61 integrates with the input idle gear 53 to transmit power from the input idle gear 53 to the front idle gear 6.

Are mounted on the intermediate shaft 8 the 1st and 2nd gear 63, the 3rd gear 64, the 6th gear 65, the 7th gear 66 and the idle gear 67, which are arranged from the clutch 41 to the torque converter 4.

The 1st and 2nd gears 63 to the 7th gear 66 are mounted on the intermediate shaft 8 so that they can rotate around the latter. The idle gear 67 rotates around the intermediate shaft 8. The idle gear 67 integrates with the idle gear 62 on the front idle shaft 6, so that power is transmitted from the idle gear 62 to idle gear 67.

The synchronizer 68 is arranged between the 1st and 2nd speeds 63 and the 3rd speed 64. The synchronizer 69 is arranged between the 6th speed 65 and the 7th speed 66.

When the 1st or 2nd gear is selected during a gear change, the synchronizer 68 joins the 1st and 2nd gear 63 to the intermediate shaft 8. When the 3rd gear is selected on the occasion a gear change, the synchronizer 68 joins the 3rd gear 64 to the intermediate shaft 8.

When the 6th gear is selected during a gear change, the synchronizer 69 joins the 6th gear 65 to the intermediate shaft 8. When the 7th gear is selected during a gear change In relation, the synchronizer 69 joins the 7th gear 66 to the intermediate shaft 8. The synchronizers 68 and 69 operate in the same way as the synchronizer 54, explanations relating thereto being omitted herein.

Are mounted on the output shaft 9 the output gear of the 1st, 2nd and 4th gear 70, the output gear of the 3rd and 5th gear 71, the output gear of the 6th gear 72, l the 7th gear output gear 73 and the final front drive gear 74, which are arranged from the clutch 41 to the torque converter 4. The output gears 70 to 73 have diameters which decrease by clutch 41 to the torque converter 4.

The output gears 70 to 73 are connected via splines to the output shaft 9 so that they rotate relative to the output shaft 9. The final front drive gear 74 is formed integrally with the output shaft 9 so that it rotates relative to the output shaft 9.

The output gear of the 1st, 2nd and 4th gear 70 integrates with the 4th gear 51 and the 1st and 2nd gear 63. The output gear of the 3rd and 5th gear 71 integrates with the 3rd gear 64 and 5th gear 52.

The output gear of the 6th gear 72 integrates with the 6th gear 65. The output gear of the 7th gear 73 integrates with the 7th gear 66.

The final front drive gear 74 integrates with the final driven gear 81B of the differential 81, so that power is transmitted from the output shaft 9 to the differential 81 via the drive gear final before 74 and the final driven gear 8IB.

The differential 81 is equipped with the differential housing 81 A, the final driven gear 81B which is mounted on the outer periphery of the differential housing 81 A, and the differential mechanism 81C disposed in the differential housing 81 A .

The left and right drive wheels 83L and 83R are coupled to the differential mechanism 81C via the left and right drive shafts 82L and 82R. The differential 81 distributes the power, generated by the motor 2, to the left and right drive shafts 82L and 82R via the differential mechanism 81C and then transmits it to the left and right drive wheels 83L and 83R.

The idle gear 84 and the idle gear 85 are mounted on the reverse idle shaft 7, the idle gear 85 having a diameter smaller than that of the idle gear 84. The idle gears 84 and 85 rotate around the reverse idle shaft 7. The idle gear 84 integrates with the input idle gear 53.

The reverse gear 86 and the final reverse drive gear 87 are mounted on the reverse shaft 10, the final reverse drive gear 87 having a diameter less than that of the step reverse 86. The final reverse drive gear 87 rotates around the reverse shaft 10.

The reverse gear 86 integrates with the idle gear 85. The final drive gear for reverse gear 87 integrates with the final driven gear 81B.

The synchronizer 88 is mounted on the reverse gear shaft 10. When the reverse gear is selected during a gear change, the synchronizer 88 joins the reverse gear 86 to the reverse gear shaft 10 .

The power is then transmitted from the final reverse drive gear 87 to the final driven gear 81B, so that the final driven gear 81B rotates in the rear direction opposite to the front direction, the vehicle thus moving backwards. Synchronizer 88 operates in the same way as synchronizer 54, more detailed explanations being omitted herein.

At Lig. 3, the torque converter box 91 comprises the upper wall 91B, the lower wall 91C, the front wall 91D, the rear wall 91E and the peripheral wall 95 (see Fig. 7). The upper wall 91B comprises the inclined rear wall 91a which is inclined forward and upwards from its rear end and the inclined front wall 91C which is inclined forward and downwards from the upper part 91b of the wall tilted rear 91a.

The bottom wall 91C is located under the top wall 91B and extends in a straight line in the longitudinal direction. The front wall 91D connects a front end of the inclined front wall 91C and a front end of the bottom wall 91C and extends in a straight line in the vertical direction.

The rear wall 91E connects a rear end of the inclined rear wall 91C and a rear end of the bottom wall 91C. The rear wall 91E is curved from the bottom wall 91C in a direction of rotation of the final driven gear 81B and extends in a straight line upwards towards the rear end of the inclined rear wall 91a. The direction of rotation of the final driven gear 81B is identical to the circumferential direction of the final driven gear 81B.

At Lig. 4, the transmission casing 92 comprises the upper wall 92B, the lower wall 92C, the front wall 92D, the rear wall 92E and the left wall 92E (see Fig. 1). The upper wall 92B comprises the inclined rear wall 92a which is inclined forward and upwards from its rear end and the inclined front wall 92C which is inclined forward and downwards from the upper part 92b of the wall tilted rear 92a.

The bottom wall 92C is located under the top wall 92B and extends in a straight line forward. The front wall 92D connects a front end of the inclined front wall 92C and a front end of the bottom wall 92C and extends in a straight line in the vertical direction.

The rear wall 92E connects a rear end of the inclined rear wall 92a and a rear end of the bottom wall 92C. The rear wall 92E is curved from the bottom wall 92C in a direction of rotation of the final driven gear 81B and extends in a straight line upwards towards a rear end of the inclined rear wall 92a. The left wall 92E is connected to the upper wall 92B, to the lower wall 92C, to the front wall 92D and to the rear wall 92E.

At Lig. 7, the peripheral wall 95 is cylindrical in shape and projects from the partition wall 94 towards the motor 2. The torque converter chamber 91A is provided in the peripheral wall 95. The upper wall 91B, the lower wall 91C, the wall front 91D and the rear wall 91E project from the partition wall 94 towards the transmission casing 92 in order to define the gear chamber 92A with the transmission casing 92.

At Lig. 2, the pump retaining device 100A and the bearing support devices 101A, 102A, 103A, 104A, 105A and 106A are formed on the partition wall 94.

The oil pump 79 is mounted on the pump retaining device 100A. More specifically, the pump retainer 100A has a pump chamber, which is not shown, in which the oil pump 79 is disposed.

The oil pump 79 is implemented by, for example, a trochoid oil pump whose internal teeth formed on an external rotor, which is not shown, and the external teeth formed on a rotor interior, which is not shown, engage with each other to define a plurality of hydraulic chambers in which the oil is stored.

In the oil pump 79, when the power, generated by the motor 2, is transmitted from the pump shaft 4a of the torque converter 4 to the inner rotor, so that the inner rotor and the outer rotor rotate in one direction, the volumes of the hydraulic chambers will successively increase or decrease in order to suck in or discharge the oil.

The brake box 32 has a contact surface which faces the partition wall 94. As illustrated in Fig. 4, the inlet port 79a and the outlet port 79b are formed in the contact surface. The partition wall 94 has a contact surface which faces the brake housing 32 as well as an inlet port and an outlet port, which are not shown, which coincide, respectively, with the inlet port 79a and outlet port 79b. In other words, an inlet port and an outlet port for the oil pump 79 are formed by the partition wall 94 and the brake housing 32.

The inlet port 79a communicates with the hydraulic chambers whose volumes increase with the rotation of the inner rotor and the outer rotor. The outlet port 79b communicates with the hydraulic chambers, the volumes of which decrease with the rotation of the inner rotor and the outer rotor.

With the above arrangements, the rotation of the inner rotor and the outer rotor causes the oil to be drawn from the intake port 79a to the hydraulic chambers. The oil is then discharged from the hydraulic chambers to the outlet port 79b, the volumes of the hydraulic chambers decreasing.

At Lig. 2, the bearing support device 101A retains one end of the front idle shaft 6 so that it can rotate using the bearing 96A. The bearing support device 102A retains one end of the reverse idle shaft 7 so that it can rotate using the bearing 96B.

The bearing support device 103A retains one end of the intermediate shaft 8 so that it can rotate using the bearing 96C. The bearing support device 104A retains one end of the output shaft 9 so that it can rotate using the bearing 96D.

The bearing support device 105A retains one end of the reverse shaft 10 so that it can rotate using the bearing 96E. The bearing support device 106A rotatably retains the cylinder 81a which is disposed on an end portion of the differential housing 81A using the bearing 96L.

[0101] In Lig. 5, the bearing support devices 100B, 101B, 102B, 103B, 104B and 105B are formed on the left wall 92L of the transmission casing 92.

The bearing support device 100B retains the end 12b of the secondary input shaft 12 so that it can rotate using the bearing 97Z (see Lig. 2). The bearing support device 101B retains one end of the front idle shaft 6 so that it can rotate using the bearing 97A (see Fig. 2).

The bearing support device 102B retains one end of the reverse idle shaft 7 so that it can rotate using the bearing 97B (see Lig. 2). The bearing support device 103B retains one end of the intermediate shaft 8 so that it can rotate using the bearing 97C (see Lig. 2).

The bearing support device 104B retains one end of the output shaft 9 so that it can rotate using the bearing 97D (see Lig. 2). The bearing support device 105B retains one end of the reverse shaft 10 so that it can rotate using the bearing 97E (see Fig. 2).

At Lig. 8, the vertical wall 98 of the transmission casing 92 faces the bearing support device 106A. The bearing support device 106B is formed on the vertical wall 98. The bearing support device 106B retains the cylinder 81b so that it can rotate using the bearing 97F. The cylinder 81b is formed on one end of the differential housing 81A (see Fig. 2).

The bearing support devices 106A and 106B have openings. The drive shafts 82L and 82R extend outside of the transmission case 90 through the openings of the bearing support devices 106A and 106B. The differential housing 81A in this embodiment constitutes an output shaft in the invention. The final driven gear 81B constitutes a rotating element in the invention.

[0107] In FIG. 4, the reverse idle shaft 7 is located above the front idle shaft 6, the intermediate shaft 8, the output shaft 9 and the reverse shaft 10 to l inside the transmission casing 90. The reverse gear shaft 10 is located below the reverse idle shaft 7.

The output shaft 9 is located above the intermediate shaft 8 under the reverse idle shaft 7 and the reverse shaft 10.

The reverse idle shaft 7 in this embodiment constitutes a first rotation shaft in the invention. The idle gear 84 or 85 constitutes a first gear in the invention. The reverse shaft 10 constitutes a second rotation shaft in the invention. Reverse 86 is a second gear in the invention.

The output shaft 9 constitutes a third rotation shaft in the invention. The output gear 70, 71, 72 or 73 constitutes a third gear in the invention.

[0111] In FIG. 7, the box-shaped oil tank 111 is arranged on the lower surfaces of the partition wall 94 and of the peripheral wall 95 of the torque converter box 91. The oil tank 111 comprises the oil 111a in which the oil is stored.

The oil tank 111 has an open bottom which is hermetically closed by the cover 11 IA so that the oil stored in the oil chamber 111a stops flowing outside the oil chamber 11 the.

In Figs. 3 and 4, the lower walls 91C and 92C of the torque converter box 91 and of the transmission case 92 have stored oil O on themselves as operating oil for the torque converter 4 and qu lubricating oil for the gear mechanism 77. A lower part of the final driven gear 81B is immersed in the oil O.

The oil strainer 112 is arranged in the torque converter box 91 and the gear chamber 92A of the transmission case 92. The oil strainer 112 comprises the strainer body 112A and the distribution orifice 112B oil. The 112A strainer body extends across the width of the vehicle and has a filter, which is not shown, inside.

The suction port 112a of the strainer body 112A is formed on a lower surface of the latter. The oil strainer 112 is arranged next to the bottom wall 92C so that the suction port 112a is immersed in the oil O inside the transmission casing 92.

The function of the filter is to remove contaminants from the oil sucked from the suction port 112a to the strainer body 112A. After filtration, the oil is discharged through the oil distribution port 112B.

[0117] At Lig. 7, the cylindrical support 113 which is formed on the partition wall 94 protrudes from the partition wall 94 in the gear chamber 92A and communicates between the gear chamber 92A and the oil chamber 11a. The oil distribution orifice 112B is installed in the support 113 so that the oil strainer 112 is held by the partition wall 94 via the support 113.

Is formed in the partition wall 94 an oil circuit, which is not shown, communicating between the oil chamber 11a and the inlet port 79a of the oil pump 79. When the oil pump 79 is actuated, the oil O stored on the lower walls 91C and 92C is sucked through the suction orifice 112a of the oil strainer 112 and percolated by the filter.

After filtration, the oil passes from the oil distribution orifice 112B to the oil chamber 111a via the support 113, then is sucked from the oil chamber 11a to the intake port 79a via the oil circuit.

The oil pump 79 distributes the oil, sucked in through the inlet port 79a, from the outlet port 79b to the torque converter 4 and to the gear mechanism 77 via an oil circuit, which is not shown.

[0121] At Lig. 4, the first bulged part 121 and the second bulged part 122 are formed on the bottom wall 92C of the transmission casing 92.

The first swollen part 121 is swollen upwards from the bottom wall 92C. Likewise, the second swollen part 122 is swollen upwards from the bottom wall 92C and is located closer to the final driven gear 81B than the first swollen part 121.

[0123] At Lig. 8, the first bulging part 121 and the second bulging part 122 extend from the flange 92R towards the flange 92L in the axial direction L of the differential housing 81 A.

The first bulging part 121 and the second bulging part 122 are, as clearly indicated in Lig. 4, formed on the threaded holes 92d formed on the flange 92R for the bolts 90A. The first bulging part 121 and the second bulging part 122 have the shape of a ramp. The first swollen portion 121 and the second swollen portion 122 each consist of a thick-walled upward bulging portion of the bottom wall 92C to form the threaded holes 92d in the bottom wall 92C. The suction port 112a of the oil strainer 112 is disposed between the first bulging part 121 and the second bulging part 122 and under the upper ends 121a and 122a of the first bulging part 121 and the second part swollen 122.

In Lig. 4 and 7, the bottom wall 92C comprises the projecting wall 123. The projecting wall 123, as illustrated in Fig. 7, extends upward from the bottom wall 92C in the same direction in which the oil strainer 112 extends.

[0127] At Lig. 4, the projecting wall 123 is interposed between the oil screen 112 and the final driven gear 81B and placed so as to overlap the suction port 112a, as can be seen in Fig. 7, in the axial direction L of the differential housing 81 A.

The bottom wall 92C includes the curved wall 124A. The curved wall 124A faces the final driven gear 81B. The curved wall 124A projects upward from the bottom wall 92C in the direction of rotation of the final driven gear 81B to form the upper end 124a. The curved wall 124A, as clearly indicated in Fig. 9, has a part which is situated under the upper end 124a and connected to the upper end 123a of the projecting wall 123.

The curved wall 124A has practically the same width as the final driven gear 81B in the axial direction L of the differential housing 81 A.

At Lig. 3, the bottom wall 94 includes the curved wall 94A. The curved wall 94A faces the final driven gear 81B and extends in the direction of rotation of the final driven gear 81B. The curved wall 94A is placed in contact with the curved wall 124A of the transmission casing 92 in the direction of the width of the vehicle.

In Lig. 7 and 8, the opening 125 is made in the contact surfaces of the curved wall 124A and the curved wall 94A. The opening 125 is located near the bottom walls 91C and 92C in the contact surfaces of the curved wall 124A and the curved wall 94A. The opening 125 communicates between the space 126A in which the final driven gear 81B is disposed and the space 126B in which the oil strainer 112 is disposed (see Fig. 4). Thus, the oil O, stored on the lower walls 91C and 92C, is transmitted to the final driven gear 81B via the opening 125.

In Lig. 6 and 7, the transmission casing 92 comprises the guide wall 124. The guide wall 124 extends in the length of the oil strainer 112 and its straight end leads to the curved wall 124A.

More specifically, the curved wall 124A is formed integrally with the guide wall 124. The curved wall 94A leads to the curved wall 124A. The curved wall 94A or the curved wall 124A in this embodiment constitutes a curved wall in the invention.

The guide wall 124 is connected to the upper end 123a of the projecting wall 123 and is integrally formed with the projecting wall 123. Consequently, the projecting wall 123 and the guide wall 124 extend in a direction in which the oil strainer 112 extends.

In Figs. 5 and 6, the transmission casing 92 comprises the first curved wall 127. The first curved wall 127 extends upwards from the guide wall 124.

The first curved wall 127 has an upper end portion which includes the first upper end 127a and the second upper end 127b. The second upper end 127b is located above the first upper end 127a in the vertical direction. The first upper end 127a and the second upper end 127b are arranged one next to the other in the axial direction of the differential housing 81 A, that is to say in the direction of the width of the vehicle.

The first curved wall 127, as can be seen in FIG. 4, faces the output gears 70, 71, 72 and 73 in the longitudinal direction and has a curved shape extending in a direction of rotation of the output gears 70, 71, 72 and 73, in other words designed so as to follow the contours of the output gears 70, 71, 72 and 73. FIG. 4 shows only the output gear 70 for the sake of brevity of the illustration.

In Figs. 5 and 6, the transmission casing 92 comprises the second curved wall 128. The second curved wall 128 extends upwards from the first upper end 127a. The second curved wall 128, as can be seen in FIG. 4, faces reverse 86 in the longitudinal direction and has a curved shape extending in the direction of rotation of reverse 86, in other words designed to follow the contours of reverse 86.

In Figs. 5 and 6, the transmission casing 92 comprises the third curved wall 129. The third curved wall 129 extends upwards from the second upper end 127b.

The third curved wall 129, as can be seen in FIG. 4, faces the idle gears 84 and 85 in the longitudinal direction and has a curved shape extending in the direction of rotation of the idle gears 84 and 85, in other words designed to follow the contours of the gears idle 84 and 85. FIG. 4 shows only the idling gear 84 for the sake of brevity of the illustration.

[0141] In FIG. 9, the guide wall 124 protrudes from a lower end of the first curved wall 127 towards the oil screen 112. The guide wall 124 has an upper end aligned with said wall, that is to say that it is located at the same height as an upper surface of the strainer body.

The oil strainer 112 is formed so as to have the strainer body 112A, the rear part of which is located under the guide wall 124, in the vertical direction. The rear portion of the strainer body 112A has the inclined rear surface 112b. The inclined rear surface 112b is inclined upward and forward from the rear end of the strainer body 112A. The guide wall 124 is inclined along the inclined rear surface 112b.

The rear part of the strainer body 112A also has the vertical rear surface 112c. The vertical rear surface 112a extends in the vertical direction. The upper part of the projecting wall 123 extends vertically along the vertical rear surface 112c.

The rear part of the strainer body 112A also has the curved lower surface 112d. The curved bottom surface 112d is curved down from the rear side to the front side of the strainer body 112A. The upper surface of the second bulged portion 122 is curved along the curved lower surface 112d. In this way, the projecting wall 123, the guide wall 124 and the second bulged part 122 are designed so as to follow the external peripheral surface of the rear part of the strainer body 112A.

At Lig. 3, is arranged on the bottom wall 91C the magnet 38 which is located closer to the final driven gear 81B than the oil strainer 112. The magnet 38 attracts the iron powder contained in the oil.

The operation will be described below. When the oil pump 79 is actuated in the transmission 1, the oil, stored in the torque converter box 91 and on the lower walls 91C and 92C of the transmission casing 92, is sucked from the suction port 112a to the strainer body 112A, then filtered in the strainer body 112A.

After filtration, the oil passes from the oil distribution orifice 112B to the oil chamber 111a via the support 113, then is sucked from the intake orifice 79a to the oil chamber 111a via the oil circuit. The oil, sucked in through the intake port 79a, is discharged into the oil circuit and transmitted to the torque converter 4 and to the gear mechanism 77.

[0148] At Lig. 4, the oil O, accumulated in the torque converter box 91 and on the lower walls 91C and 92C of the transmission casing 92, is projected upwards by the final driven gear 81B which rotates clockwise d 'an R watch to create the oil flow 01.

The oil flow O1 flows from the inclined rear wall 92a along the inclined front wall 92c before falling and disappearing, thereby lubricating the gears on the front idle shaft 6, the idle shaft 7, the intermediate shaft 8, the output shaft 9 and the reverse shaft 10.

The flow of oil O1 also flows along the front wall 92D, like the flow of oil 02, then falls on the bottom wall 92C so as to accumulate on the bottom wall 92C. The oil on the bottom wall 92C is then projected upwards by the final driven gear 81B, so as to be collected in the center of the bottom wall 92C in the longitudinal direction due to a drop in speed relative to the flow oil 01.

The oil strainer 112 in this embodiment is located in the center of the bottom wall 92C where the oil is collected. Although not illustrated, the oil flows 01 and 02 move the upper wall 91B, the lower wall 91C, the front wall 91D and the rear wall 91E of the torque converter box 91 connected to the transmission casing 92 .

As evidenced by the preceding discussion, the transmission 1 in this embodiment comprises the torque converter box 91 and the transmission casing 92 with the lower walls 91C and 92C on which the oil O is accumulated. The transmission 1 also includes the differential housing 81A equipped with the final driven gear 81B which is retained by the torque converter box 91 and the transmission casing 92 so as to be able to rotate and project the oil O upwards.

The transmission 1 also includes the oil strainer 112 which extends in the axial direction of the differential housing 81A and is arranged in the torque converter box 91 and the transmission casing 92. When the oil pump 79 is actuated, the oil strainer 112 sucks in the oil O, accumulated on the lower walls 91C and 92C, through the suction orifice 112a.

The bottom wall 92C comprises the first bulged part 121 and the second bulged part 122. The first bulged part 121 is swollen upwards from the bottom wall 92C. The second swollen portion 122 is swollen upward from the bottom wall 92C and is located closer to the final driven gear 81B than the first swollen portion 121.

The suction port 112a of the oil strainer 112 is disposed between the first bulging part 121 and the second bulging part 122 and under the upper ends 121a and 122a of the first bulging part 121 and the second part swollen 122.

With the previous arrangements, the first swollen part 121 and the second swollen part 122 act as obstacles to the collection and accumulation of oil between the first swollen part 121 and the second swollen part 122. This guarantees the stability of the suction of the oil accumulated between the first bulged part 121 and the second bulged part 122 in the oil strainer 112.

Consequently, the use of the first bulged part 121 and the second bulged part 122 of the bottom wall 92C makes it possible to avoid the aspiration of air into the oil strainer 112, thus increasing the efficiency. of the oil pump 79 in terms of oil suction.

The transmission 1 in this embodiment is equipped with the bottom wall 92C which has the projecting wall 123. The projecting wall 123 projects upwards from the bottom wall 92C and extends in the same direction in which the oil strainer 112 extends. The projecting wall 123 is disposed between the oil screen 112 and the final driven gear 81B and placed so as to overlap the suction port 112a in the axial direction of the differential housing 81 A.

Consequently, when the oil flow 02 which flows from the front wall 92D on the bottom wall 92C passes over the first bulged part 121 towards the second bulged part 122, it is blocked by the projecting wall 123 .

Therefore, when the oil circulates rapidly, for whatever reason, between the first swollen part 121 and the second swollen part 122, the projecting wall 123 acts as a plug in order to accumulate the oil between the first bulging part 121 and the second bulging part 122.

The above arrangements allow the oil strainer 112 to suck up the oil flowing slower and which is accumulated between the first swollen part 121 and the second swollen part 122. This makes it possible to avoid aspiration air in the oil strainer 112, which increases the efficiency of the oil pump 79 in terms of oil suction.

The transmission 1 in this embodiment is equipped with curved walls 94A and 124A which project upwards from the bottom walls 91C and 92C in the direction of rotation of the final driven gear 81B. The curved wall 124A has a portion which is located under the upper end 124a and connected to the upper end 123a of the projecting wall 123.

In addition, the curved walls 94A and 124A have the opening 125 which communicates between the space 126A in which the final driven gear 81B is disposed and the space 126B in which the oil strainer 112 is disposed .

The oil which falls therefrom is therefore collected by the curved walls 94A and 124A and distributed to the final driven gear 81B and to the oil strainer 112.

The oil distributed to the oil strainer 112, as indicated by the flow of oil 03 to the Lig. 9, flows between the first bulged part 121 and the second bulged part 122 via a gap between a wall leading from the curved wall 124A to the projecting wall 123 and towards the second bulged part 122 and the strainer body 112A.

The oil flow 03 mixes with the oil flow 02 which fell from the front wall 92D onto the bottom wall 92C and flowed in the gap between the first swollen part 121 and the second swollen part 122, thus facilitating the accumulation of oil between the first bulged part 121 and the second bulged part 122.

This makes it possible to avoid the suction of air into the oil strainer 112 and to enhance the efficiency of the oil pump 79 in terms of oil suction.

In addition, the oil flows 02 and 03 which flow between the first swollen part 121 and the second swollen part 122 are transmitted via the opening 125 in the space 126A in which the final driven gear 81B is arranged, then projected upwards by the final driven gear 81B.

This promotes the circulation of the oil inside the transmission casing 92, thus facilitating the lubrication of the gear mechanism 77, the aspiration of the oil into the oil strainer 112 and the transmission of the oil from the oil pump 79 to the gear mechanism 77 and to the torque converter 4.

The transmission 1 in this embodiment has the transmission housing 92 equipped with the guide wall 124 which extends in the direction in which the oil strainer 112 extends and has the end at which leads the curved wall 124A. The guide wall 124 is connected to the upper end of the projecting wall 123.

The transmission casing 92 is equipped with the first curved wall 127 which extends upwards from the guide wall 124 and faces the output gears 70, 71, 72 and 73. The first curved wall 127 has of the upper end portion which includes the first upper end 127a and the second upper end 127b which are located side by side in the axial direction of the differential housing 81 A. The second upper end 127 is located above the first upper end 127a in the vertical direction.

The transmission casing 92 comprises the second curved wall 128 and the third curved wall 129. The second curved wall 128 extends upwards from the first upper end 127a and faces the reverse gear 86. The third wall curved 129 extends upward from the second upper end 127b and faces the idle gears 84 and 85. The guide wall 124 also projects from the lower end of the first curved wall 127 toward the oil strainer 112 .

After lubrication of the teeth engaged in the reverse gear 86 and the idling gear 85, the oil comes into contact with the second curved wall 128 and the third curved wall 129 due to the rotation of the reverse gear 86 and the idling gear 85, flows, as indicated by the oil flows 04 and 05 at Eig. 6, along the second curved wall 128 and the third curved wall 129, then reaches, as indicated by the oil flows 06, the first curved wall 127.

After lubrication of the integrated teeth of the gears 63 to 66 and the output gears 70 to 73, the oil, as indicated by the oil flows 06, flows along the first curved wall 127 with the rotation output gears 70 to 73.

The oil 06 which flows on the first curved wall 127 is temporarily stopped by the upper surface of the guide wall 124 protruding from the first curved wall 127 towards the oil strainer 112. Part of the oil 06 which overflows from the guide wall 124 passes through the curved wall 124A and the curved wall 94A before reaching the final driven gear 81B and being projected upwards by the final driven gear 81B.

Oil 01, projected upwards by the final driven gear 81B, lubricates the inside of the transmission case 90 before being sucked into the oil strainer 112.

The oil overflowing from the upper surface of the guide wall 124 passes through, as indicated by the flow of oil 07 at Lig. 9, a gap between a wall (which extends from the guide wall 124 to the projecting wall 123 and to the second bulging part 122) and the strainer body 112A, enters a gap between the first bulging part 121 and the second swollen part 122, then mixes with the oil flow 02.

Consequently, the above arrangements allow a large amount of oil to mix with the oil flow 02, guaranteeing the stability of the oil accumulation between the first swollen part 121 and the second swollen part 122. This reduces the risk that the oil strainer 112 unintentionally sucks in air, which increases the efficiency of the oil pump 79 in terms of oil suction.

The oil flow 06 on the first curved wall 127 comes into contact with the upper surface of the guide wall 124, so that the speed of the oil flow 06 decreases, which minimizes the agitation of the oil accumulated between the first swollen part 121 and the second swollen part 122 by the oil flow 07 flowing towards the oil screen 112. This guarantees the stability of the oil accumulation between the first swollen part 121 and the second bulging part 122.

The oil flow 07 is an oil flow moving from the assembly of the guide wall 124 towards the oil screen 112. The oil flow 03 is an oil flow moving from the guide wall 124 towards the oil screen 112. Consequently, the volume of the oil flow 07 is greater than that of the oil flow 03.

The transmission 1 in this embodiment has the oil strainer 112 whose rear part is located under the guide wall 124. The guide wall 124 protrudes from the lower end of the first curved wall 127 towards oil strainer 112.

[0182] Consequently, when the oil, as illustrated in Lig. 6 and 9, circulates rapidly, for whatever reason, between the first bulged part 121 and the second bulged part 122 before reaching the projecting wall 123, the projecting wall 123 serves to return said flow of oil along the guide wall 124. In other words, the projecting wall 123 deflects the oil flow upward in the forward direction without allowing it to flow in a straight line in the rearward direction.

This reduces the speed of the oil which moves from the projecting wall 123 along the guide wall 124. This increases the efficiency of the oil accumulation between the first swollen part 121 and the second bulging portion 122.

The transmission 1 in this embodiment has the oil strainer 112 equipped with the strainer body 112A which is designed to follow the outer peripheries of the guide wall 124, the projecting wall 123 and the second bulging part 122.

This allows a large amount of oil to be transmitted via a gap between the wall (which extends from the guide wall 124 to the projecting wall 123 and to the second bulging portion 122) and the body of strainer 112A between the first bulging part 121 and the second bulging part 122. This strengthens the oil suction capacity of the oil pump 79.

The first bulged part 121 and the second bulged part 122 in this embodiment consist of thick parts of the bottom wall 92C which are swollen upward to form the threaded holes 92d in the bottom wall 92C; alternatively, they can also consist of thin-walled parts of the bottom wall 92C as long as they are swollen upwards.

[0187] Although the present invention has been disclosed by setting out the preferred embodiment in order to facilitate understanding, it should be noted that the invention can be carried out in different ways, without departing from the principle of invention.

Consequently, the invention must be interpreted so as to include all the modifications which could be made to the embodiment presented without departing from the principle of the invention indicated in the claims.

Claims (1)

claims [Claim 1] Transmission for vehicle (1) comprising: a transmission case (92) which has a bottom wall (92C) on which oil is accumulated; an output shaft (9) which is retained by the transmission casing so that it can rotate and is equipped with a rotary element (81B) projecting the oil upwards; and an oil strainer (112) which extends in an axial direction from the output shaft inside the transmission case and is actuated by an oil pump (79) to suck the accumulated oil on the lower wall (92C), via a suction orifice (112a), wherein the bottom wall (92C) comprises a first bulging part (121) and a second bulging part (122), the first bulging part being swollen upwards from the bottom wall (92C), the second bulging part being swollen towards the high from the bottom wall (92C) and being located closer to the rotary element (81B) than the first bulged part is, and wherein the suction port (112a) of the oil strainer is disposed between the first swollen portion and the second swollen portion and is also located under the upper ends (121a, 122a) of the first swollen portion (121) and the second swollen part (122). [Claim 2] A vehicle transmission (1) according to claim 1, wherein the bottom wall (92C) comprises a projecting wall (123) which projects upwards from the bottom wall and extends in the same direction in which the strainer oil (112) extends, and in which the projecting wall is arranged between the oil strainer and the rotary element (81B) and placed so as to overlap the suction orifice (112a) in the axial direction of the output shaft (9). [Claim 3] A vehicle transmission (1) according to claim 2, wherein the bottom wall (92C) includes a curved wall (124A) which faces the rotating member (81B) and projects upward from the bottom wall in a direction of rotation of the rotary member, in which a part of the curved wall is located below an upper end (124a) projecting from the curved wall (124A) and is connected to an upper end (123a) of the wall in projection (123), and in which the curved wall (124A) has an opening (125) which communicates between the space (126A) in which the rotary element is [Claim 4] [Claim 5] [Claim 6] disposed and the space (126B) in which the oil strainer (112) is disposed. A vehicle transmission according to claim 3, further comprising a first rotation shaft (7), a second rotation shaft (10) and a third rotation shaft (9), the first rotation shaft being located on an upper side of the transmission casing and equipped with a first gear (84, 85), the second rotation shaft being located below the first rotation shaft and equipped with a second gear (86), the third rotation shaft being located below the first rotation shaft and the second rotation shaft and equipped with a third gear (70, 71, 72, 73), in which the transmission housing comprises (a) a guide wall (124) which extends in the direction in which the oil strainer (112) extends, which has one end to which the curved wall (124A) leads and which is connected to the upper end (123a) of the projecting wall (123 ), (b) a first curved wall (127) which extends upwards from the guide wall (124) so as to face the third gear and which has an upper end part comprising a first upper end (127a) and a second upper end (127b), the second upper end lying next to the first upper end in the axial direction of the output shaft (9) and above the first upper end, (c) a second curved wall (128) which extends upwards from the first upper end and faces the second gear, and (d) a third curved wall (129) which extends upwards from the second upper end and faces the third gear, and wherein the guide wall (124) projects from the first curved wall (127) toward the oil screen (112). A vehicle transmission according to claim 4, wherein the oil strainer (112) is arranged so that one of its parts is located under the guide wall (124). Vehicle transmission according to claim 4 or 5, in which the guide wall (124), the projecting wall (123) and the second bulging part (122) are designed so as to follow the outer periphery of the oil strainer (112).