JP3518769B2 - Forward / reverse switching device for continuously variable transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forward / reverse switching device for a continuously variable transmission. 2. Description of the Related Art A conventional forward / reverse switching device for a continuously variable transmission is disclosed in Japanese Patent Application Laid-Open No. 3-204436. The forward / reverse switching device of the continuously variable transmission shown in this figure has a forward clutch drum provided integrally with a sun gear, and a hub provided integrally with a carrier. The forward clutch drum and the hub are integrally rotatable when the clutch plate that rotates integrally with each other is brought into a fastened state. The sun gear has an oil passage that penetrates the inner diameter portion and the outer diameter portion thereof and that can output oil between the hub and the forward clutch drum, and an oil passage that can output oil to the gear portion of the sun gear. Is formed. [0003] However, the conventional forward / reverse switching device for a continuously variable transmission has a problem that the lubricating efficiency of the clutch plate of the forward clutch is not sufficient. That is, the oil supplied from the oil passage of the sun gear is discharged toward the inside of the drum-shaped hub for lubrication of the forward clutch, so that the oil is supplied to the clutch plate disposed on the outer peripheral portion of the drum-shaped hub. Will not flow enough. The present invention is to solve such a problem. [0004] The present invention relates to a sun gear,
The above problem is solved by forming an oil passage capable of outputting oil between the gear portion and the hub connecting portion and supplying oil along the back surface of the drum-shaped hub. That is, the forward / reverse switching device of the continuously variable transmission according to the present invention includes a set of planetary gear units, a forward clutch, and a reverse brake, and the planetary gear unit includes a sun gear, an internal gear, And a carrier that rotatably supports a pinion gear that meshes with both gears at the same time.
And the internal gear, a fastening or releasably and Sangi A, the reverse brake is fastened or releasably carrier to the casing, the internal gear is always connected to the input shaft through the drum of the forward clutch, the sun gear is In a forward / reverse switching device of a continuously variable transmission, which is always connected to an output shaft, a hub is provided integrally with one end of a sun gear, and the hub is in a drum shape and its outer peripheral portion is away from the sun gear. It has a cylindrical part that extends to
A spline is formed on the outer periphery of the cylindrical portion, a clutch plate of a forward clutch is meshed with the spline, and an oil passage penetrating from the inner diameter portion to the outer diameter portion is formed in the sun gear. The outlet on the outer diameter portion side of the sun gear is located between the gear portion of the sun gear and the hub coupling portion. [0005] The oil output between the gear portion and the hub coupling portion through the oil passage formed in the sun gear flows toward the outer periphery of the sun gear by centrifugal force generated by rotation of the sun gear. Move radially. That is, part of the oil lubricates the sun gear, pinion gear and internal gear, and the remaining part reaches the forward clutch along the back surface of the hub. Thereby, the planetary gear device and the forward clutch can be lubricated with the oil output from one oil passage. FIG. 2 shows a power transmission mechanism of a continuously variable transmission. The continuously variable transmission includes a torque converter 12 (which may be a fluid coupling), a forward / reverse switching mechanism 15, a V-belt continuously variable transmission mechanism 29, and a differential device 56.
The rotation of the output shaft 10 of the engine can be transmitted to the drive shafts 66 and 68 at a predetermined speed ratio and a predetermined rotation direction. The continuously variable transmission includes a torque converter 12 (pump impeller 12a, turbine runner 12
b, a stator 12c, a lock-up clutch 12d, etc.), a rotating shaft 13, an output shaft 14, a forward / reverse switching mechanism 15, a drive pulley 16 (a fixed cone member 18, a drive pulley cylinder chamber 20, a movable cone member 22). V-belt 24, driven pulley 26 (fixed cone member 30, driven pulley cylinder chamber 32, movable cone member 34)
, The driven shaft 28, the driving gear 46, the idler gear 48, the idler shaft 52, the pinion gear 54, the final gear 44, the pinion gear 58, the pinion gear 60,
It is composed of a side gear 62, a side gear 64, a drive shaft 66, a drive shaft 68, and the like, but a detailed description thereof will be omitted except for the forward / reverse switching device 15. The configuration of a portion whose description has been omitted is described in JP-A-61-105353 filed by the present applicant. FIG. 1 shows a portion of the forward / reverse switching device 15 of the continuously variable transmission shown in FIG. A forward clutch drum 70 is provided integrally with the input shaft 13. A piston 71 is fitted on the forward clutch drum 70, and an oil chamber 89 is formed by these pistons. The piston 71 is always receiving a return force by the spring 72. The piston 71 can apply a pressing force to the clutch plates 73 and 74 that are alternately superimposed. The clutch plate 73 rotates integrally with the forward clutch drum 70, while the clutch plate 74
Each is connected by a spline so as to rotate integrally with a hub 76 integrated with the hub. The hub 76 is welded to one end of the sun gear 75 so as to be integrated therewith. The hub 76 has a drum shape, and has a cylindrical portion on the outer periphery extending in a direction away from the sun gear 75,
A spline that engages with the clutch plate 74 is provided on the outer periphery of the cylindrical portion. Forward clutch drum 70
Are connected so that the internal gear 77 rotates integrally. Internal gear 77 and sun gear 75
At the same time, a meshing pinion gear 78 is rotatably supported by a carrier 79. In addition, sun gear 7
5. The planetary gear unit 19 is constituted by the internal gear 77, the pinion gear 78, and the carrier 79.
The carrier 79 has a disk-shaped wall portion 79b orthogonal to the axial direction.
1, and a cylindrical portion 79a extending rightward in FIG. 1, that is, surrounding the outer peripheral side of the forward clutch drum 70. That is, the carrier 79
Is formed in a drum shape, and a pinion gear 78 is rotatably supported inside the drum shape. Carrier 7
The cylindrical portion 79a of 9 is configured as a spline, and the clutch plate 81 with an inner diameter spline meshes with the spline. On the other hand, the clutch plate 82 with the outer diameter spline which is alternately overlapped with the clutch plate 81 with the inner diameter spline is formed by the spline 8 of the casing 83.
3a. A reverse brake piston 84 can apply a pressing force to the clutch plate 81 with the inside diameter spline and the clutch plate 82 with the outside diameter spline. The reverse brake piston 84 is fitted to a cylinder 83b formed in the casing 83. An oil chamber 85 is formed between the reverse brake piston 84 and the cylinder 83b. Reverse brake piston 84
Is always returned by the spring 86.
The spring 86 is held by a spring retainer 87. The spring retainer 87 has a notched inner diameter except for a portion where the spring 86 is disposed, and the cutout portion is formed by a protruding portion on the tip side of the reverse brake piston 84 (where the spring 86 is disposed). (Excluding the portion) passes through to reach the clutch plate 81 with the inner diameter spline and the clutch plate 82 with the outer diameter spline. The sun gear 75 is spline-coupled to rotate integrally with the output shaft 14 rotatably supported by the bearing 88. Carrier 7
Reference numeral 9 denotes a first thrust bearing 100 on a side facing the sun gear 75 on the inner diameter side of the wall portion 79b, and a second thrust bearing 102 on a side facing the inner diameter side bearing 88 of the wall portion 79b. It is arranged between the sun gear 75 and the bearing 88 through the intermediary. An oil passage 104 is formed in the sun gear 75 so as to penetrate between the outer diameter portion of the gear portion 75a and the connecting portion of the hub 76 and the inner diameter portion. Oil can be supplied to the oil passage 104 through an oil passage 120 connected to a hydraulic pressure source, an orifice 121, and an oil passage 122 formed in the input shaft 13. Oil is
The oil is output from the oil passage 104 to the right side in FIG. 1 of the hub 76 through the oil passage 130 between the gear portion 75a and the coupling portion of the hub 76 through the oil passage 104. The forward clutch 40 is constituted by the forward clutch drum 70, the piston 71, the spring 72, the clutch plate 73, the clutch plate 74, etc. The cylinder 83b, the reverse brake piston 84, the clutch plate 81 with an inner diameter spline, the outer diameter The reverse brake 50 is constituted by the clutch plate 82 with splines and the like. Next, the operation of this embodiment will be described. First, when moving forward, the forward clutch 40 is engaged,
Further, the reverse brake 50 is released. That is, the oil chamber 89 between the forward clutch drum 70 and the piston 71
The oil chamber 85 formed by the cylinder 83b and the reverse brake piston 84 is in a drain state. As a result, the clutch plate 73 and the clutch plate 74 are brought into the engaged state by the frictional force,
The forward clutch drum 70 and the sun gear 75 are connected via the hub 76. On the other hand, since the internal gear 77 is always connected to the forward clutch drum 70, both the internal gear 77 and the sun gear 75 rotate integrally with the forward clutch drum 70. For this reason, the planetary gear device 19 is in a locked state and rotates integrally as a whole. Therefore, the forward clutch drum 7
0 (that is, the rotation of the input shaft 13)
5 (that is, transmitted directly to the output shaft 14). Thereby, the input shaft 13 and the output shaft 1
4 together rotate in the same direction. During this time, the oil passes through the oil passage 120, the orifice 121, the oil passage 122 of the input shaft 13, and the oil passage 104 of the sun gear 75, and is output between the gear portion 75 a of the sun gear 75 and the joint of the hub 76. The oil radially moves in the outer circumferential direction of the sun gear 75 due to the centrifugal force generated by the rotation of the sun gear 75. Thus, oil is supplied to the planetary gear device 19 and the forward clutch 40. In particular, some of the oil
6, the lubrication of the clutch plates 73 and 74 of the forward clutch 40 is performed efficiently. further,
Oil flows along the surface of the hub 76 (the right side surface in FIG. 1) through the oil passage 130 to lubricate the forward clutch 40. The oil that has passed through the oil passage 122 lubricates the thrust bearings 100 and 102 through the oil passage 106 of the sun gear 75. Next, when the vehicle is set in the reverse traveling state, the oil chamber 89 of the forward clutch 40 is set in the drain state, and the hydraulic pressure is applied to the oil chamber 85 of the reverse brake 50. This allows
The reverse brake piston 84 applies a pressing force to the clutch plate 81 with the inner diameter spline and the clutch plate 82 with the outer diameter spline, and the carrier 79 is moved to the casing 83.
To be fixed. The internal gear 77 is always connected to the input shaft 13 via the forward clutch drum 70. Therefore, the internal gear 77 is the engine 1
0 rotates in the same direction as the output shaft 10a. As described above, since the carrier 79 is fixed, the sun gear 75
Rotates in the direction opposite to the rotation direction of the internal gear 77. Therefore, the rotation of the output shaft 14 with respect to the rotation of the input shaft 13
Is rotated in the opposite direction. Thereby, the reverse state is realized. In this case, the rotation of the output shaft 14 is increased by the gear ratio of the internal gear 77 and the sun gear 75. Also at this time, the oil passage 104
The oil is output between the gear portion 75a of the sun gear 75 and the coupling portion of the hub 76 through the oil passage. This oil moves radially in the direction of the outer diameter of the forward / reverse switching device 15 due to the centrifugal force, so that the oil is supplied to the planetary gear device 19 and the forward clutch 40. The forward / reverse switching device 15 requires a different amount of oil for lubricating the forward and reverse travels. This is because the amount of oil may be small when the vehicle is moving forward because there is no relative rotation of the gears. On the other hand, when the vehicle is moving backward, the gears are relatively rotated and the clutch plates 73 and 74 of the forward clutch 40 are rotated in opposite directions to each other. This is because the amount of oil increases. In order to change the amount of oil to be supplied in response to this, a hydraulic circuit as shown in FIG. 3 can be provided (note that FIG. 3 shows a lubricating circuit including only the forward / reverse switching device 15). is there). That is, the oil passage that connects the cooler 110 and the forward / reverse switching device 15 is branched into two oil passages 112 and 114 on the way.
Are directly connected to the forward / reverse switching device 15, and the other oil passage 114 is connected to the forward / reverse switching device 15 via the switching valve 116. The switching valve 116 can control the opening and closing of the oil passage 114. The switching valve 116 is switched by hydraulic pressure from the reverse brake 50. That is, the switching valve 116
When hydraulic pressure is supplied to the reverse brake 50,
When the hydraulic pressure of the reverse brake 50 is discharged when the brake 14 is opened, the oil passage 114 operates to be closed. As a result, the oil is supplied to the forward / reverse switching device 15 only from the oil passage 112 during forward movement, and is supplied to the forward / reverse switching device 15 from the oil passage 112 and the oil passage 118 during reverse movement.
Therefore, the amount of oil supplied to the forward / reverse switching device 15 can be reduced during forward travel that does not require much lubrication, and the amount of oil supplied to the forward / reverse switching device 15 can be increased during reverse travel requiring much lubrication. According to the present invention, the sun gear is provided with a hub, and the sun gear penetrates the oil passage between the gear portion of the outer diameter portion and the hub coupling portion and the inner diameter portion. By forming, the planetary gear device and the forward clutch can be lubricated with the oil output from one oil passage. In particular, since the oil is caused to flow along the rear surface of the hub, the amount of oil to the forward clutch is increased. Thereby, lubrication efficiency can be increased.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an embodiment of the present invention. FIG. 2 is a diagram showing a configuration of an entire continuously variable transmission. FIG. 3 is a view showing an oil passage for lubrication of the forward / reverse switching device. [Description of Signs] 14 Output shaft 75 Sun gear 75a Gear section 76 Hub 77 Internal gear 78 Pinion gear 79 Carrier 19 Planetary gear device 88 Bearing 40 Forward clutch 50 Reverse brake

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akito Suzuki 2 Nissan Motor Co., Ltd., Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture (56) References JP-A-61-105353 (JP, A) JP-A-4 -83953 (JP, A) JP-A-2-95059 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 3/44 F16H 3/60 F16H 37/02 F16H 57/04

Claims (1)

(57) [Claim 1] It has a set of planetary gears, a forward clutch, and a reverse brake. The planetary gears include a sun gear, an internal gear, consists of a pinion gear that meshes simultaneously with gears and a rotatably supported to the carrier, the forward clutch and the internal gear is a Sangi a <br/> engagement or releasably, the reverse brake is the carrier in the casing The internal gear is always connected to the input shaft via the drum of the forward clutch, and the sun gear is always connected to the output shaft. A hub is provided integrally with this,
The hub has a drum shape, and has a cylindrical portion extending in a direction away from the sun gear on an outer peripheral portion. A spline is formed on the outer periphery of the cylindrical portion, and a clutch plate of a forward clutch is engaged with the spline. In the sun gear, an oil passage is formed that penetrates from the inner diameter portion to the outer diameter portion.
Located between the gear part of the sun gear and the hub coupling part,
A forward / reverse switching device for a continuously variable transmission.