JP3228174B2 - Belt type transmission for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt type transmission for a vehicle which changes the gear ratio steplessly by changing the groove width of a pulley.

[0002]

2. Description of the Related Art Conventionally, there has been developed a continuously variable automatic transmission which continuously changes gears as an automatic transmission mounted on a vehicle such as an automobile. As such a continuously variable automatic transmission, for example, a belt-type transmission in which an endless belt is stretched between a pair of pulleys configured to be able to change a groove width, so-called CVT (= Continuously Variable Transmissi
on) is widely known.

The above-mentioned pair of pulleys has a drive pulley (or a drive pulley or an input pulley) to which a rotational driving force is input from the engine side and a driven pulley to which the rotational driving force of the drive pulley is input via an endless belt. A pulley (or a driven pulley) is used. Such a change in the groove width of each pulley is generally performed by a hydraulic piston mechanism using high-pressure hydraulic oil.

An example of the structure of a conventional drive pulley will be briefly described below. The drive pulley is composed of a fixed pulley fixed in the axial direction and a movable pulley movable in the axial direction. Are supported by a primary shaft integrally formed with the fixed pulley. The movable pulley is provided with a hydraulic piston mechanism.

On the other hand, the primary shaft is formed hollow, and an oil pump drive shaft for driving an oil pump is inserted into the primary shaft. Further, an oil passage through which high-pressure hydraulic oil pressurized by the oil pump flows is provided between the inner peripheral side of the primary shaft and the outer peripheral side of the oil pump drive shaft. High-pressure hydraulic oil is supplied through this oil passage.

[0006] A seal member (for example, a seal ring or a metal bush) is interposed in the oil pump drive shaft, and an oil formed between the primary shaft and the oil pump drive shaft by this seal member. The liquid tightness of the road is maintained.

[0007]

By the way, in order to drive the movable pulley, high-pressure hydraulic oil is required. Therefore, high-pressure hydraulic oil is also supplied to the oil passage. If the processing accuracy of the surface in contact with the seal member is low, it is conceivable that hydraulic oil leaks from between the seal surface and the seal member. In addition, if the processing accuracy of the sealing surface is low, the wear between the sealing surface and the sealing member is increased, and the durability of the sealing member is reduced. For this reason, high machining accuracy is required for the sealing surface of the primary shaft.

However, if the contact surface of the primary shaft with the seal member is located substantially at the center of the primary shaft in the axial direction, there has been a problem that it is difficult to form the surface with high precision. In other words, usually such a seal surface is processed by a precision finishing using a cutting tool such as a reamer. However, if the seal surface is located at the back as viewed from the axial direction of the primary shaft, the tooth tip This requires a long cutting tool, which makes high-precision surface machining of the seal surface difficult. In addition, there is also a problem that the accuracy of the work is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has made it possible to easily and accurately process the inner peripheral surface of a shaft abutting on such a sealing member.
An object of the present invention is to provide a belt type transmission for a vehicle.

[0010]

According to the present invention, there is provided a belt type transmission for a vehicle according to the present invention, wherein a power transmission means for inputting a driving force from an engine through an engine-side drive shaft; A drive pulley connected to the power transmission means via an input shaft; and a driven pulley to which the rotational driving force of the drive pulley is transmitted via an endless belt stretched over the drive pulley. A belt type transmission for a vehicle that changes a gear ratio between the driving pulley and the driven pulley by changing a groove width of the driven pulley,
An oil pump connected to the engine drive shaft and driven by an oil pump drive shaft extending through the input shaft and the rotation shaft of the drive pulley; and an inner peripheral side of the drive pulley and the oil pump. A first oil passage through which hydraulic oil is supplied from the oil pump is formed between the outer peripheral side of the pump drive shaft and an inner peripheral side of the drive pulley and the first hydraulic passage near the shaft end of the drive pulley. At least one of an outer peripheral side of the oil pump drive shaft and a first projecting toward the other of the outer peripheral side of the oil pump drive shaft or the inner peripheral side of the drive pulley.
Is formed, and the liquid tightness of the first oil passage is maintained between the first protrusion and the other of the outer peripheral side of the oil pump drive shaft or the inner peripheral side of the drive pulley. It is characterized in that a first seal member is interposed as much as possible.

According to a second aspect of the present invention, there is provided a belt type transmission for a vehicle according to the first aspect of the present invention, further comprising an inner peripheral side of the input shaft and an outer peripheral side of the oil pump drive shaft. A second oil passage is formed therebetween, the first oil passage is connected to the oil pump, and the second oil passage is connected to a supply port formed in the input shaft. A second protruding portion is formed on at least one of the inner peripheral side of the oil pump drive shaft and the outer peripheral side of the oil pump drive shaft to project toward the outer peripheral side of the oil pump drive shaft or the other of the inner peripheral side of the input shaft. With
A second seal member is interposed between the second projecting portion and the outer peripheral side of the oil pump drive shaft or the other of the inner peripheral side of the input shaft to maintain the liquid tightness of the second oil passage. The first oil passage and the second oil passage are defined by the first seal member.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A belt type transmission for a vehicle as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing the entire configuration, FIG. 2 is an enlarged view of the transmission mechanism, and FIG. 3 is a schematic cross-sectional view showing the main configuration. First, as shown in FIG.
This transmission includes a casing 1 for housing an internal mechanism.
Is provided. The casing 1 can be divided into two parts by a torque converter housing (housing member) 3 and a transmission case 5, and is fastened by bolts 1a. The torque converter housing 3 is integrally formed with a partition 3a for dividing the space inside the casing 1 into two, and the torque converter housing 3 and the transmission case 5 are divided on one plane. It is configured as follows.

A first shaft 2 and a second shaft 2 are provided inside the casing 1.
A shaft (secondary shaft) 4 and a third shaft (transfer shaft) 6 are provided, and the rotational driving force input to the first shaft 2 is transmitted via the secondary shaft 4 and the transfer shaft 6 to a differential (differential mechanism). 2
7 and the left and right output shafts (drive shafts) 24
Is driven.

As shown in FIGS. 1 and 2, the first shaft 2
A torque converter (power transmission means) 8, a forward / reverse switching mechanism 10, a drive pulley (drive pulley) 12, an oil pump 13 and the like are provided in this order from the engine side. Pulley) 18, a parking gear 16, a transfer drive gear 14, and the like. Further, a transfer driven gear 20 and a final drive pinion gear 22 are provided on the transfer shaft 6.
The final drive pinion gear 22 includes a final gear 26 provided on an output shaft (drive shaft) 24.
Is engaged.

The first shaft 2 includes a hollow input shaft (input shaft) 2A and a hollow primary shaft 2B integrally formed with a part of the drive pulley 12. In addition, these input shafts 2
An oil pump drive shaft 2C is provided in A and the primary shaft 2B so as to be relatively rotatable.

The input shaft 2A is supported by a reaction shaft 36a, a reaction shaft support 36b, and the like. Incidentally, the torque converter 8 is housed in the above-described torque converter housing 3 as shown in FIG. 2, and the rotational driving force output from the torque converter 8 is transmitted through the input shaft 2A to the forward / reverse switching mechanism. 10.

Here, the torque converter 8 is configured similarly to a normal automatic transmission, and includes a pump 8a, a turbine 8b and a stator 8c.
Is provided. The pump 8a is connected to the engine crankshaft via a drive plate 8d,
When the pump 8a is rotationally driven, the torque converter 8
The rotational energy of the pump 8a is transmitted to the turbine 8b via the working oil inside. The turbine 8b is spline-coupled to the input shaft 2A via a turbine hub 8e, and the input shaft 2A is rotationally driven by the rotational driving force transmitted to the turbine 8b. The torque converter has a direct connection (lock-up) mechanism for directly transmitting the driving force from the drive plate 8d to the turbine 8b.

Further, the rear side of the torque converter 8 (FIG. 2)
A middle / left side) is provided with a forward / reverse switching mechanism 10. The forward / reverse switching mechanism 10 includes an input shaft 2
The purpose is to switch the rotation direction of the rotational driving force transmitted from A to the primary shaft 2B, and to cut off the transmission of the driving force to the primary shaft 2B. Here, the forward / reverse switching mechanism 10 is housed in a cylindrical case (switching mechanism case) 28 as shown in FIG. 2, and the planetary gear mechanism 30, the clutch 32 and the brake 34 are accommodated in the cylindrical case 28. Etc. are provided. Note that the cylindrical case 28 is attached to the partition wall 3a of the torque converter housing 3 with bolts 28a to improve the rigidity of the entire transmission.

The planetary gear mechanism 30 is configured as a double pinion type planetary gear mechanism having two pinion gears, and includes a sun gear 30a, a first pinion gear 30b,
It comprises a second pinion gear 30c, a planetary carrier 30d and an annulus gear (ring gear) 30e. As shown in FIG. 2, in this embodiment, the sun gear 30a is formed integrally with the input shaft 2A. The first pinion gear 30b and the second pinion gear 30c are supported by a planetary carrier 30d while meshing with each other. The first pinion gear 30b is connected to the sun gear 30a, and the second pinion gear 30c is connected to the annular gear 3d.
0e.

The planetary carrier 30d is provided with a shaft support 30d-1 provided at the end on the drive pulley 12 side.
And the shaft support portion 30d-1 is connected to the drive pulley 12
And splines are joined. In addition, the above-mentioned brake 3
4 is the outer peripheral side of the annulus gear 30e and the cylindrical case 2
8 and the annulus gear 3
0e is provided to regulate the rotation. The brake 34 engages with the annulus gear 30e to rotate integrally with the annulus gear 30e.
a and the cylindrical case 28
, A plurality of brake plates 34b fixed in the rotation direction with respect to
4b are alternately arranged. A cylindrical brake piston 34c is provided at an end of the cylindrical case 28 on the side of the drive pulley 12, and hydraulic oil is supplied to a hydraulic chamber 34d formed between the cylindrical case 28 and the brake piston 34c. Is supplied, the brake piston 34c is driven rightward in FIG. 2 against the urging force of the return spring 34e, and comes into contact with the brake plate 34b.

Then, as described above, the brake piston 34
When c is driven, the brake plate 34b is pressed by the brake piston 34c, and each plate 34a,
The rotation of the annulus gear 30e is regulated by the frictional force between 34b. On the other hand, the clutch 32 is provided so as to regulate the relative rotation between the sun gear 30a and the planetary carrier 30d. Like the brake 34, the clutch disks 32a and the clutch plates 32b are alternately provided. It is arranged. Here, the clutch disc 32a is engaged with a cylindrical portion extending in the axial direction from the main body of the planetary carrier 30d, so that the clutch disc 32a and the planetary carrier 30d rotate integrally.

The clutch plate 32b meshes with a spline of a cylindrical portion outside the clutch retainer 32f shown in FIG. 2, and rotates integrally with the clutch retainer 32f. Here, the clutch retainer 32
f is a member that is supported while sliding on the reaction shaft support 36 and is spline-coupled to the input shaft 2A, whereby the clutch plate 32b rotates integrally with the sun gear 30a and the input shaft 2A. I have.

A clutch actuating piston 32c is provided at an end of the clutch retainer 32f.
When hydraulic oil is supplied to a hydraulic chamber 32d formed between the clutch retainer 32f and the clutch piston 32c,
The clutch piston 32c is driven leftward in FIG. 2 against the urging force of the return spring 32e, and comes into contact with the clutch plate 32b.

The clutch piston 32
When c is driven, the clutch plate 32b is pressed by the clutch piston 32c, and each plate 32a,
The relative rotation between the sun gear 30a and the planetary carrier 30d is regulated by the frictional force between the sun gears 32b, and the planetary carrier 30d rotates integrally with the sun gear 30a.

Therefore, when the clutch 32 is turned on and the brake 34 is turned off, the planetary carrier 30d
And the sun gear 30a rotate integrally, and the sun gear 30
The rotational driving force input to “a” is transmitted to the primary shaft 2B of the drive pulley 12 as it is. That is, in this case, the input shaft 2A and the drive pulley 12 rotate at a constant speed.

When the clutch 32 is turned off and the brake 34 is turned on, the annulus gear 30e is fixed to the cylindrical case 28. Therefore, when a rotational driving force is input to the sun gear 30a, the first pinion gear 30b and the second pinion gear 30c revolve in the direction opposite to the rotation direction of the sun gear 30a while rotating, thereby causing the pinion carrier 30d to rotate. Also sun gear 3
It rotates in the direction opposite to 0a.

Further, when both the clutch 32 and the brake 34 are turned off, the rotational driving force from the input shaft 2A to the primary shaft 2B is cut off, and a neutral state is set. Thus, the forward / reverse switching mechanism 10
Thus, by controlling the operation of the clutch 32 and the brake 34, switching control of the rotation direction transmitted to the drive pulley 12 is performed.

In this embodiment, the forward / reverse switching mechanism 1
Although a double-pinion type planetary gear mechanism 30 is used for 0, the forward / reverse switching mechanism 10 is not limited to such a mechanism, but is a single pinion type planetary gear mechanism or a synchromesh type planetary gear mechanism. A switching mechanism may be used. By the way, at a position adjacent to the forward / reverse switching mechanism 10,
A drive pulley (drive pulley) 12 is provided.
The drive pulley 12 includes a fixed pulley 12a formed integrally with the primary shaft 2B, and a movable pulley 1 provided on the primary shaft 2B and movable in the axial direction.
2b, and a substantially conical power transmission surface 12a-
1, 12b-1 are formed. The pulleys 12a, 12b-1 are connected by the power transmission surfaces 12a-1, 12b-1.
A V-shaped groove 12c is formed between 12b.

One end (the right end in FIG. 2) of the primary shaft 2B is connected to the shaft support 3 of the planetary carrier 30d.
Od-1 and the cylindrical case 28 via the bearing 40
The other end (the left end in FIG. 2) is supported by the transmission case 5 via a bearing 42. In the present apparatus, as described above, the primary shaft 2B is pivotally supported on the end of the cylindrical case 28, so that the bearing distance (or bearing span, see FIG. 1) of the primary shaft 2B can be reduced. As a result, the rigidity of the primary shaft 2B is improved. That is, a large bending moment acts on the primary shaft 2B in the direction of the secondary shaft 4 by a steel belt (endless belt) 44 described later. It is possible to improve the bending stiffness against a great tension.

In this transmission, the primary shaft 2B and the planetary carrier 30d are spline-connected to each other near the position where the bearing 40 of the cylindrical case 28 is provided. That is, as shown in FIG. 2, at the disposition position of the bearing 40, the outer peripheral portion of the primary shaft 2B and the inner peripheral portion of the shaft support portion 30d-1 of the planetary carrier 30d mesh with the spline, and further, the shaft support portion 30d The outer peripheral side of -1 is axially supported by the bearing 40.

The other end (left end in FIG. 2) of the primary shaft 2B is supported by the transmission case 5 via a bearing 42. And, in this way, on the inner peripheral side of the bearing 40, the primary shaft 2B
And the planetary carrier 30d are spline-coupled, so that the forward / reverse switching mechanism 10 and the drive pulley 12 can be configured to be highly rigid and compact. Further, as will be described in detail later, such a configuration makes it possible to easily assemble the transmission.

On the other hand, a driven pulley (driven pulley) 18 is provided on the secondary shaft 4 at a position facing the drive pulley 12. The driven pulley 18 is configured similarly to the drive pulley 12, and includes a fixed pulley 18a and a movable pulley 18b.
In addition, substantially conical power transmission surfaces 18a-1 and 18b-1 are formed on opposing surfaces of the respective pulleys 18a and 18b, and a V-shaped groove 18c is also formed.

A steel belt 44 as an endless belt is stretched between the groove 12c of the drive pulley 12 and the groove 18c of the driven pulley 18, and the drive pulley 12 is driven to rotate via the steel belt 44. The force is transmitted to the driven pulley 18. That is, on the drive pulley 12 side, the rotational driving force of the drive pulley 12 is transmitted to the steel belt 44 by the frictional force between the steel belt 44 and the power transmission surfaces 12a-1 and 12b-1, and the driven pulley 18 side Is the steel belt 44 and the power transmission surface 18a-
Driven pulley 1 due to the frictional force between
8 is driven to rotate.

The distance between the fixed pulleys 12a and 18a and the movable pulleys 12b and 18b,
By changing the widths of c and 18c, the gear ratio is changed. Therefore, the drive pulley 12
The movable pulley 12b is driven to drive the driven pulley 12b.
A hydraulic piston mechanism 60 for changing the width of the groove 12c is additionally provided.

Here, the drive pulley 12 and the hydraulic piston mechanism 60 will be described.
Is provided on a primary shaft 2B integrally formed with the fixed pulley 12a via a ball spline mechanism 46, and the rotation of the movable pulley 12b relative to the primary shaft 2B is restricted by the ball spline mechanism 46. , Are provided so as to be movable in the axial direction.

On the other end (left end in FIG. 2) of the primary shaft 2B, a cylindrical wall 48 which rotates integrally with the primary shaft 2B and extends in the direction of the movable pulley 12b.
A cylinder portion 48 having a is provided. A cylindrical wall portion 12b-2 is formed on the outer peripheral side of the movable pulley 12b so as to cover the cylindrical wall portion 48a of the cylinder portion 48. Further, two pistons 50 and 52 are disposed in a space formed by such a cylinder portion 48 and the movable pulley 12b.
A hydraulic chamber 54 is formed by the cylinder 0 and the cylinder portion 48, and a hydraulic chamber 56 is formed by the piston 52 and the movable pulley 12b.

Here, the piston 50 is connected to the movable pulley 12
b, and is restricted from moving relative to the movable pulley 12b in the axial direction. Further, the piston 52 is in contact with the distal end portion of the wall portion 48a of the cylinder portion 48, and the relative movement in the axial direction with respect to the cylinder portion 48 is restricted. Further, seal members are interposed between the piston 50 and the cylinder portion 48 and between the piston 52 and the movable pulley 12b, respectively, so that the fluid tightness of the hydraulic chambers 54 and 56 is maintained. .

The hydraulic oil is supplied to these hydraulic chambers 54 and 56 simultaneously by control means (controller) (not shown). Therefore, the hydraulic chamber 5
When the hydraulic oil is supplied to 4, the piston 50 is driven rightward in FIG. 2, and the movable pulley 12b is driven rightward in FIG. Further, when hydraulic oil is supplied to the hydraulic chamber 56, the piston 52 is pressed to the left in the drawing, but the axial position of the piston 52 is regulated by the wall portion 48a of the cylinder portion 48. The movable pulley 1
2b is driven to the right in the figure.

As described above, the hydraulic piston mechanism 60 for moving the movable pulley 12b is a double piston hydraulic piston mechanism having two pistons 50 and 52, because the groove width of the drive pulley 12 is reduced. This is because a large force is required when the movable pulley 12b is narrowed (when the movable pulley 12b is driven rightward in the figure). For this purpose, it is conceivable to increase the pressure itself of the supplied hydraulic oil. However, by adopting the hydraulic piston mechanism 60 having the double piston as described above, the pressure receiving area of the hydraulic oil can be reduced within a limited space. Can be approximately doubled, and a large force can be efficiently obtained.

The oil pressure is supplied by an oil pump 13. The oil pump 13 is attached to the transmission case 5 on the rear end side (rear side) of the first shaft 2, and is driven by an oil pump drive shaft 2C. Further, as described above, the oil pump drive shaft 2C is disposed so as to be relatively rotatable in the input shaft 2A and the primary shaft 2B, and is mounted so as to rotate integrally with the engine crankshaft.

The rotational driving force inputted to the driven pulley 18 is transmitted from the transfer drive gear 14 on the secondary shaft 4 to the transfer driven gear 20 on the transfer shaft 6 shown in FIG. Here, as shown in FIG. 2, the secondary shaft 4 is connected to a fixed pulley 18 of the driven pulley 18.
a one end (right end in the figure) is supported by the torque converter housing 3 via a bearing 64, and the other end (left end in the figure) is supported by the transmission case 5 via a bearing 66. I have.

In the secondary shaft 4,
A hydraulic oil supply path 4a is formed in the axial direction, and hydraulic oil for driving the movable pulley 18b is supplied through a hydraulic oil supply path 5a formed on the transmission case 5 side. As shown in FIG. 2, the driven pulley 18 includes the drive pulley 12 described above.
Similarly to the above, a movable pulley 18b is provided on the secondary shaft 4 via a ball spline mechanism 68,
The ball spline mechanism 68 regulates the relative rotation of the movable pulley 18b with respect to the secondary shaft 4, and is provided so as to be movable in the axial direction.

The driven pulley 18 is provided with a hydraulic piston mechanism 62 for driving the movable pulley 18b in the axial direction to change the width of the groove 18c of the driven pulley 18. Here, the hydraulic piston mechanism 62 will be described. On the outer peripheral side of the movable pulley 18b, a cylindrical wall portion 70 extending in a direction opposite to the power transmission surface 18b-1 is formed. A piston (secondary piston) 72 is provided on the inner peripheral side of the cylindrical wall portion 70, and the outer peripheral edge of the secondary piston 72 comes into contact with the inner peripheral surface of the cylindrical wall portion 70. .

A hydraulic chamber 74 is formed by the cylindrical wall 70 and the secondary piston 72.
The secondary piston 72 is fixed in both the axial direction and the rotational direction with respect to the secondary shaft 4, and a return spring 76 that contacts the secondary piston 72 and the movable pulley 18 b is disposed in the hydraulic chamber 74. I have. The secondary piston 72 and the movable pulley 1
A seal member is interposed between the hydraulic chamber 74 and the hydraulic chamber 74.

Therefore, when the hydraulic oil is not supplied to the hydraulic chamber 74, only the urging force (preload) of the return spring 76 acts on the movable pulley 18b, and the movable pulley 18b is urged to the left in the drawing. . A desired frictional force is generated between the power transmission surfaces 18a-1 and 18b-1 and the steel belt 44 by the biasing force, and a certain clamping force (clamping force) is generated.
8 is driven to rotate without slipping.

Next, the operation at the time of shifting between the drive pulley 12 and the driven pulley 18 will be described.
When the gear ratio is changed to the low speed side, the hydraulic oil in the hydraulic chambers 54 and 56 is discharged on the drive pulley 12 side, and the movable pulley 12b is moved (driven) to the left in the drawing. The width of the groove 12c increases, and the radius of rotation of the steel belt 44 on the drive pulley 12 side decreases.

On the driven pulley 18 side, the operating oil is supplied to the hydraulic chamber 74 via the operating oil supply oil passages 5a and 4a, so that the movable pulley 18b is driven to the left in the figure. That is, the width dimension of the groove 18c of the driven pulley 18 is reduced, and the radius of rotation of the steel belt 44 is increased. That is, the gear ratio of the pulley is as follows: gear ratio = (belt rotation radius on driven pulley 18 side) / (belt rotation radius on drive pulley 12 side) (1) That is, it is on the low speed side.

Also during the gear shifting, the hydraulic chambers 54, 56 on the drive pulley 12 side and the hydraulic chamber 78 on the driven pulley 18 side.
The appropriate hydraulic oil also acts on the movable pulleys 12b and 18b.
, A desired frictional force is generated between the power transmission surfaces 12a-1 and 12b-1 and between the power transmission surfaces 18a-1 and 18b-1 and the steel belt 44.
Can be transmitted to the driven pulley 18 at a low speed.

When the gear ratio is changed to a higher speed, hydraulic fluid is supplied to the hydraulic chambers 54 and 56 on the drive pulley 12 side, so that the movable pulley 12b is driven rightward in the drawing. The width of the groove 12c is reduced, and the radius of rotation of the steel belt 44 on the drive pulley 12 side is increased.
On the driven pulley 18 side, the hydraulic oil in the hydraulic chamber 74 is discharged, so that the movable pulley 18b moves leftward in the drawing, the width of the groove 18c increases, and the turning radius of the steel belt 44 decreases. . Therefore, the gear ratio becomes smaller according to the above equation (1), and becomes higher.

The hydraulic chamber 5 on the drive pulley 12 side
4, 56 and the hydraulic chamber 74 on the driven pulley 18 side also act on the movable pulleys 12b, 1
8b generates an urging force, and the power transmission surfaces 12a-1, 12b
-1 and the power transmission surfaces 18a-1 and 18b-1 generate a desired frictional force between the steel belt 44 and the driving force from the drive pulley 12 can be transmitted to the driven pulley 18 at a high speed. .

When the secondary shaft 4 rotates at a high speed in a state where the hydraulic oil is supplied to or remains in the hydraulic chamber 74, a large centrifugal force acts on the hydraulic oil in the hydraulic chamber 74. Such a centrifugal force is proportional to the square of the distance from the rotation center, and acts not only in the rotation radius direction but also in all directions of the hydraulic chamber 74. Therefore,
When hydraulic oil is interposed in the hydraulic chamber 74, the pressure in the hydraulic chamber 74 becomes high during rotation of the secondary shaft 4, especially during high-speed rotation, and a force is generated that urges the movable pulley 18b to the left in the drawing. As a result, a clamping force higher than a desired clamping force is generated. In this case, a desired gear ratio may not be achieved, or wear may occur between the driving force transmitting surfaces 18a-1, 18b-1 and the steel belt 44.

Therefore, in this vehicle belt type transmission,
A centrifugal balance chamber 78 is provided outside the hydraulic chamber 74 so that the hydraulic pressure due to such a centrifugal force is canceled. That is, as shown in FIG. 2, the hydraulic piston mechanism 62 is provided with a balancing cap 80 that covers the cylindrical wall portion 70 and the secondary piston 72, and the centrifugal balance chamber is formed by the balancing cap 80 and the secondary piston 72. 78 is formed.

The balancing cap 80 is fixed to the cylindrical wall 70, and the centrifugal balance chamber 78
Have holes 4b provided in the secondary shaft 4,
Hydraulic oil is supplied via a hole 16a provided in the parking gear 4c and the parking gear 16. Therefore, when the secondary shaft 4 rotates, particularly at high speed, centrifugal force causes the hydraulic oil to have a high pressure particularly on the outer peripheral side in the hydraulic chamber 74 and generates a force to expand the volume of the hydraulic chamber 74. At the same time, the hydraulic oil in the centrifugal balance chamber 78 also becomes high in pressure due to the centrifugal force, and a force for expanding the volume of the centrifugal balance chamber 78 is generated. As a result, the force acting on the balancing cap 80 (the force acting in the right direction in the figure) and the force acting on the movable pulley 18b (the force acting in the left direction in the figure) cancel each other, so that the movable pulley 18b is driven. Power is canceled.

On the other hand, on the secondary shaft 4, adjacent to the hydraulic piston mechanism 62, the parking gear 16
And a transfer drive gear 14.
Each of these gears 16 and 14 is spline-coupled to the secondary shaft 4.
It is constituted so that it may rotate integrally. As shown in FIG. 1, the transfer drive gear 14 meshes with a transfer driven gear 20 spline-coupled to the transfer shaft 6, and the transfer drive gear 14 and the transfer driven gear 20 Is reduced and transmitted to the transfer shaft 6.

The parking gear 16 restrains the rotation of the secondary shaft 4. When a transmission lever (not shown) is operated to a parking position (P position), a parking sprag (not shown) is engaged with the parking gear 16. The rotation of the secondary shaft 4 is restricted. FIG.
As shown in FIG. 5, the transfer shaft 6 has one end (the right end in the drawing) supported by the torque converter housing 3 via a bearing 90 and the other end (the left end in the drawing) connected to the transmission case 5 via a bearing 92. It is supported by.

The bearing 90 is directly attached to the torque converter housing 3. On the other hand, the bearing 92 is a bearing retainer 9 as shown in FIG.
4 and the bearing retainer 94
Are attached to the transmission case 5 by bolts 96. In addition, the transfer shaft 6 includes
The final drive pinion gear 22 is formed integrally, and the final drive pinion gear 22 meshes with a final gear 26 provided on the output shaft 24. The driving force transmitted from the final drive pinion gear 22 is transmitted to the differential 27 via the final gear 26, and the left and right drive shafts 24 are driven.

Next, the main part of the vehicle belt-type transmission according to the present invention will be described mainly with reference to FIG. One end (right end in the figure) of the oil pump drive shaft 2C is connected to an engine-side drive shaft (not shown), and the oil pump 13 (see FIGS. 1 and 2) is driven by the rotational driving force of the oil pump drive shaft 2C. It is supposed to be.

As shown in FIG. 3, the inner peripheral side of the primary shaft 2B and the oil pump drive shaft 2C
An oil passage (first oil passage) 120 to which hydraulic oil is supplied from the oil pump 13 is formed between the oil passage 13 and the outer peripheral side. The hydraulic oil supplied to the first oil passage 120 is a control hydraulic oil for operating the hydraulic piston mechanism 60, and is pressurized to a predetermined pressure by the oil pump 13.

The primary shaft 2B is provided with a hole 122 communicating with the first oil passage 120, and the movable pulley 12b is provided with a hydraulic piston mechanism 60.
A hole 124 communicating with the hydraulic chamber 56 is formed.
The hydraulic oil supplied to the first oil passage 120 is supplied to the hydraulic chamber 56 through the holes 122 and 124.

Further, as shown in FIG.
A hole 46a is formed in the radial direction in the vicinity of the ball spline mechanism 46 of b, and the working oil in the first oil passage 120 is supplied to the hydraulic chamber 54 through the hole 46a. ing. And in this way, each hydraulic chamber 54,
56, the drive pulley 1
The second movable pulley 12b is driven in the axial direction.

Incidentally, in the present apparatus, as shown in FIG. 3, the protruding portion (the second end) is provided near the shaft end of the primary shaft 2B (that is, the shaft end of the drive pulley 12 and the right end in the drawing). One protruding portion) 130 is formed.
The first protruding portion 130 includes a protruding portion 126 protruding from the inner peripheral side of the primary shaft 2B toward the outer peripheral side of the oil pump drive shaft 2C, and a primary shaft 2B protruding from the outer peripheral side of the oil pump drive shaft 2C.
And a protrusion 128 protruding toward the inner peripheral side of the protrusion.
8 are formed at positions facing each other.

The oil pump drive shaft 2C
An annular groove 132 is formed in the projecting portion 128 in the circumferential direction, and a seal ring (first seal member) 134 is attached to the groove 132. Then, the outer peripheral surface of the seal ring 134 contacts the inner peripheral surface of the protruding portion 126, so that the liquid tightness of the first oil passage 120 is maintained. In addition, this seal ring 1
34 has a rectangular cross section, for example, and its surface is processed by Teflon processing.

By the way, in the above description, the first protrusion 1
The reason why 30 is provided at the axial end portion of the primary shaft 2B is that a surface (hereinafter, referred to as a seal surface) of the primary shaft 2B that comes into contact with the seal ring 134 is easily and accurately processed. That is, the movable pulley 12b
High pressure hydraulic oil is required to drive the oil passage, and high pressure hydraulic oil is also supplied to the oil passage 120. However, if the processing accuracy of the above-mentioned seal surface is low, this seal surface and the seal It is conceivable that hydraulic oil leaks from between the ring 134. In addition, if the processing accuracy of the seal surface is low, the wear between the seal surface and the seal ring 134 increases, and the durability of the seal ring 134 decreases. For this reason, high processing accuracy is required for the sealing surface of the primary shaft 2B. However, when the protruding portion 130 as described above is formed at the back of the primary shaft 2B (near the center of the primary shaft 2B). However, it is difficult to form the sealing surface with high precision.

That is, normally, such processing of the sealing surface is performed by the primary shaft 2B (that is, the fixed pulley 12).
After forming the protruding portion 126 in a), precise finishing is performed by a cutting tool such as a reamer. However, if the protruding portion 126 is formed in the back of the primary shaft 2B, a cutting tool having a long tooth tip is required, and There is a problem that accuracy is reduced.

Therefore, in the present belt type transmission,
By forming the first protrusion 130 near the shaft end of the primary shaft 2B, the sealing surface can be easily processed with high precision. As a result, the wear between the seal surface and the seal ring 134 is reduced, the durability of the seal ring 134 is greatly improved, and leakage of hydraulic oil from the first oil passage 120 is also reliably prevented. It is.

In the above description, the first protruding portion 130 extends from the inner peripheral side of the primary shaft 2B toward the outer peripheral side of the oil pump drive shaft 2C.
6 and a projection 128 projecting from the outer periphery of the oil pump drive shaft 2C toward the inner periphery of the primary shaft 2B.
0 does not necessarily need to be constituted by the two protrusions 126 and 128 described above. For example, primary shaft 2
B is formed on at least one of the inner peripheral side of B and the outer peripheral side of the oil pump drive shaft 2C, and a protruding portion 130 protruding toward the other is formed. The first seal member 134 may be interposed therebetween.

Now, as shown in FIG. 3, the inner peripheral side of the input shaft 2A and the oil pump drive shaft 2C
Between the first oil passage 120 and the first oil passage 120 adjacent to the first oil passage 120 (second oil passage).
40 are formed. The second oil passage 140 is an oil passage provided to supply hydraulic oil (in this case, functioning as a lubricating oil) into the forward / reverse switching mechanism 10, and therefore, the second oil passage 140 is supplied with a relatively low-pressure hydraulic oil.

The input shaft 2A has a second shaft.
The oil hole 142 communicating with the oil passage 140 is provided, and the planetary carrier 30d of the forward / reverse switching mechanism 10 has a hole for further supplying the lubricating oil supplied from the hole 142 to the inside of the forward / backward switching mechanism 10. 144 are formed. Further, the input shaft 2A is also provided with a hole 156 for supplying lubricating oil between the reaction shaft support 36 and the partition 3a of the converter housing 3.

Then, such holes 142, 144,
Through 156, the working oil (lubricating oil) in the second oil passage 140 is supplied to a desired portion such as the forward / reverse switching mechanism 10. On the other hand, a second protrusion 150 is formed between the input shaft 2A and the oil pump drive shaft 2C. This second protrusion 15
As shown in FIG. 3, reference numeral 0 denotes a protruding portion 146 projecting from the inner peripheral side of the input shaft 2A toward the outer peripheral side of the oil pump drive shaft 2C, and The two projections 146 and 148 protrude toward the peripheral side.
Are formed at positions facing each other.

The oil pump drive shaft 2C
The protrusion 148 has an annular groove 152 formed in the circumferential direction, and a seal ring (second seal member) 154 is attached to the groove 152. Then, the outer peripheral surface of the seal ring 154 contacts the inner peripheral surface of the protruding portion 146, so that the liquid tightness of the second oil passage 140 is maintained.

Incidentally, as described above, the first oil passage 1
A high-pressure hydraulic oil for control is supplied to the inside of the pump 20.
A relatively low-pressure hydraulic oil equivalent to lubricating oil is supplied into the oil passage 140 of the first oil passage 120 and the second oil passage 14.
It is necessary to reliably prevent the operating oil in the first oil passage 120 from being mixed into the second oil passage 140 by partitioning the oil passage into 0.

On the other hand, in the vehicle belt type transmission, the first oil passage 120 and the second oil passage 140 are defined by the first seal member 134 described above.
It is possible to reliably prevent the mixing of the hydraulic oil as described above. That is, as described above, the first oil passage 1
By forming the first protruding portion 130 in the vicinity of the axial end of the primary shaft 2B, the sealing surface of the primary shaft 2B that contacts the first seal member 134 can be easily processed with high precision. , First
The first oil passage 120 and the second oil passage 140 are reliably shielded by the seal member 134 of the first oil passage 120 and the second oil passage 140.
The hydraulic oil can be prevented from being mixed with the oil passage 140.

As shown in FIG. 3, the second projecting portion 150 is formed relatively at the back of the input shaft 2A, but unlike the first oil passage 120, the second oil passage Since the hydraulic oil supplied to 140 has a relatively low pressure,
It is not necessary to process the sealing surface with higher precision than the first protrusion 130 of the primary shaft 2B.
There is no problem even if the projection 150 is formed relatively deep in the input shaft 2A.

Further, similarly to the above-mentioned first projecting portion 130, the second projecting portion 150 does not necessarily need to be constituted by the above-mentioned two projecting portions 146 and 148. That is,
At least one of the inner peripheral side of the input shaft 2A and the outer peripheral side of the oil pump drive shaft 2C is formed with a protrusion 130 protruding toward the other.
30 and a second seal member 154 between the oil pump drive shaft 2C and the other of the input shaft 2A.
May be interposed.

Since the vehicular belt-type transmission as one embodiment of the present invention is configured as described above, the driving force from the engine is transmitted to the forward / reverse switching mechanism 10 via the torque converter 8. You. In addition, forward / reverse switching mechanism 1
At 0, the operation of the clutch 32 and the brake 34 is controlled, so that the drive pulley 12 is switched between forward rotation, reverse rotation, and neutral. Then, the rotational driving force input to the drive pulley 12 is transmitted to the driven pulley 18 via the steel belt 44.

The rotational driving force input to the secondary shaft 4 via the driven pulley 18 is transmitted from the transfer drive gear 14 to the transfer driven gear 20 on the transfer shaft 6. The rotational driving force of the secondary shaft 4 is reduced by the transfer drive gear 14 and the transfer driven gear 20 and transmitted to the transfer shaft 6.

The rotational driving force input to the transfer shaft 6 is applied to the final drive pinion gear 22.
And output to the left and right drive shafts 24 via the final gear 26. The gear ratio between the drive pulley 12 and the driven pulley 18 is determined by the pulleys 12 and 18.
Can be changed by adjusting the width of the groove. That is, the gear ratio can be increased by driving the movable pulley 12b rightward in the drawing by the hydraulic piston mechanism 60 to reduce the groove width of the drive pulley 12, and the movable piston 18b of the driven pulley 18 by the hydraulic piston mechanism 62. Is driven in the left direction in the figure to reduce the groove width of the driven pulley 18, whereby the gear ratio can be reduced.

The hydraulic chambers 54 and 56 of the hydraulic piston mechanism 60 are supplied from the oil pump 13 driven by the oil pump drive shaft 2C to the first oil passage 12
Hydraulic oil is supplied through 0. Here, the first oil passage 1
Reference numeral 20 is formed between the inner peripheral side of the primary shaft 2B and the outer peripheral side of the oil pump drive shaft 2C, and the first seal member 134 makes the primary shaft 2B and the oil pump drive shaft 2C liquid-tight. Is held.

In the belt type transmission for a vehicle,
By forming the first protrusion 130 with which the seal ring 134 abuts on the shaft end of the primary shaft 2B,
A normal cutting tool can be used, and high-precision finishing can be easily performed. In addition, leakage of hydraulic oil in the first oil passage 120 is thereby reliably prevented.

On the other hand, a second oil passage 140 formed between the inner peripheral side of the input shaft 2A and the outer peripheral side of the oil pump drive shaft 2C is provided to the forward / reverse switching mechanism 10 and the like.
Hydraulic oil (lubricating oil) is supplied through the holes 142, 144, and 150. Incidentally, high-pressure hydraulic oil for control is supplied into the first oil passage 120, and the first oil passage 1
A relatively low-pressure hydraulic oil equivalent to lubricating oil is supplied to the second oil passage 140 adjacent to the first oil passage 120.
It is necessary to reliably shield the space between the first oil passage 120 and the second oil passage 140.
A first seal member 134 is provided between the first seal member 134 and the second oil passage 140.
, The inside of the second oil passage 140 and the first
The hydraulic oil is reliably prevented from being mixed with the inside of the oil passage 120.

As described above, in the vehicle belt-type transmission according to the present invention, the surface of the primary shaft 2B in contact with the first seal member 134 can be machined with high accuracy.
Thus, there is an advantage that leakage of hydraulic oil in the first oil passage 120 can be reliably prevented. In addition, there is an advantage that the wear of the first seal member 134 can be reduced and the durability of the first seal member can be greatly improved. Further, since the finishing process of the contact surface with the first seal member 134 can be performed relatively easily with high precision, the manufacturing cost is also advantageous.

The vehicle belt-type transmission of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

[0083]

As described above in detail, according to the belt type transmission for a vehicle according to the first aspect of the present invention, the surface where the first protrusion and the first seal member come into contact with high accuracy. Processing can be performed, thereby advantageously preventing leakage of hydraulic oil in the first oil passage. In addition, thereby, the wear between the first protrusion and the first seal member can be reduced, and the durability of the first seal member can be greatly improved. In addition, since such high-precision finishing can be performed relatively easily, the manufacturing cost is also advantageous.

According to the belt type transmission for a vehicle according to the second aspect of the present invention, the first oil passage and the second oil passage can be reliably shielded, and the first oil passage can be prevented. There is an advantage that the working oil can be prevented from being mixed between the passage and the second oil passage.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an overall configuration of a vehicle belt-type transmission as one embodiment of the present invention.

FIG. 2 is an enlarged view showing a transmission mechanism in a vehicle belt-type transmission as one embodiment of the present invention.

FIG. 3 is an enlarged view showing a main part of a belt type transmission for a vehicle as one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Casing 2 1st shaft 2A Input shaft (input shaft) 2B Primary shaft 2C Oil pump drive shaft (oil pump drive shaft) 3 Torque converter housing 3a Partition wall 3b Hole part (support part) 4 2nd shaft (secondary shaft) 5 Transmission Case 6 Third shaft (transfer shaft) 8 Torque converter 8a Pump 8b Turbine 8c Stator 8d Drive plate 8e Plate 10 Forward / reverse switching mechanism 12 Drive pulley (drive pulley) 12a Fixed pulley 12b Movable pulley 12a-1, 12b-1 Power transmission Surface 12b-2 Cylindrical wall portion 12c Groove 13 Oil pump 14 Transfer drive gear 16 Parking gear 18 Driven pulley (driven pulley) 18a Fixed pulley 18b Movable pulley 18a Reference Signs List 1, 18b-1 power transmission surface 18c groove 20 transfer driven gear 22 final drive pinion gear 24 output shaft (drive shaft) 26 final gear 27 differential 28 cylindrical case (switching mechanism case) 28a bolt 30 planetary gear mechanism 30a sun gear 30b 1 pinion gear 30c 2nd pinion gear 30d Planetary carrier 30d-1 Shaft support 30e Annulus gear (ring gear) 32 Clutch 32a Clutch disk 32b Clutch plate 32c Clutch piston 32d Oil chamber 32e Return spring 32f Clutch retainer 34 Brake disk 34B Brake plate 34c Brake piston 34d Oil chamber 34e Return spring 36 Reaction shaft Lift support 40, 42 Bearing 44 Steel belt (endless belt) 46 Ball spline mechanism 48 Cylinder part 48a Wall part 50, 52 Piston 54, 56 Hydraulic chamber 60, 62 Hydraulic piston mechanism 64 66 Bearing 68 Ball spline mechanism 70 Cylindrical wall part 72 Piston (secondary piston) 74 Hydraulic chamber 76 Return spring 78 Centrifugal balance chamber 80 Balancing cap 90, 92 Bearing 94 Bearing retainer 96 Bolt 120 First oil passage 122, 124 Hole 126, 128 Projection 130 First projection 132 Groove portion 134 Seal ring (first seal member) 140 Second oil passage 142, 144, 156 Oil hole 146, 148 Projection portion 150 Second projection portion 152 Groove portion 154 Seal ring (second seal) Le member)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16H 9/00-9/26 F16H 57/00 F16H 57/04

Claims (2)

(57) [Claims] 1. A power transmission means for inputting a driving force from an engine via an engine-side drive shaft, a drive pulley connected to the power transmission means via an input shaft, and And a driven pulley to which the rotational driving force of the driving pulley is transmitted via an endless belt, and changing the groove width of the driving pulley and the driven pulley to change the speed between the driving pulley and the driven pulley. A belt-type transmission for changing the ratio, comprising: an oil pump connected to the engine drive shaft and driven by an oil pump drive shaft extending through the input shaft and the rotation shaft of the drive pulley. In addition, a first oil passage for supplying hydraulic oil from the oil pump is formed between an inner peripheral side of the drive pulley and an outer peripheral side of the oil pump drive shaft, and a shaft end of the drive pulley is provided. Neighborhood In addition, at least one of the inner peripheral side of the drive pulley and the outer peripheral side of the oil pump drive shaft, a first projecting toward the other of the outer peripheral side of the oil pump drive shaft or the inner peripheral side of the drive pulley. A projection is formed, and the first oil passage is kept liquid-tight between the first projection and the other of the outer peripheral side of the oil pump drive shaft or the inner peripheral side of the drive pulley. A belt type transmission for a vehicle, characterized in that a first seal member is interposed as much as possible. 2. A second oil passage is formed between an inner peripheral side of the input shaft and an outer peripheral side of the oil pump drive shaft, and the first oil passage is connected to the oil pump.
The second oil passage is connected to a supply port formed in the input shaft, and at least one of an inner peripheral side of the input shaft and an outer peripheral side of the oil pump drive shaft, an outer peripheral side of the oil pump drive shaft or A second protruding portion is formed to protrude toward the other of the inner peripheral side of the input shaft, and the second protruding portion and the other of the outer peripheral side of the oil pump drive shaft or the inner peripheral side of the input shaft A second seal member is interposed between the first oil passage and the second oil passage to maintain the liquid tightness of the second oil passage. The vehicle belt-type transmission according to claim 1, wherein the transmission is partitioned.