JP2003301902A - Vehicular belt type transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a miniaturizable vehicular belt type transmission by avoiding the interference of a parking gear with its surrounding mechanisms. <P>SOLUTION: The vehicular belt type transmission for changing a speed ratio between a driving pulley 12 and a driven pulley 18 by changing a groove width of the driving pulley 12 and the driven pulley 18 comprises the parking gear 16 arranged between a torque converter housing 3 and the driven pulley 18 for integral rotation with the driven pulley 18, the parking gear 16 having a web 16a displaced from a toothed face 16b thereof in the opposite direction to the driven pulley 18. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt type speed change device for a vehicle, which continuously changes the speed change ratio by changing the groove width of a pulley.

[0002]

2. Description of the Related Art Conventionally, a continuously variable automatic transmission that continuously changes gears has been developed 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 whose groove widths can be changed, so-called CVT (= Continuously Variable Transmissio).
n) is widely known.

In such an automatic transmission, a driver operates a transmission lever provided in a vehicle compartment to select a shift range (shift position), and automatic transmission is performed according to the shift range. Be done.
As such a shift range, there are provided a parking range for stopping the vehicle during parking, a reverse range for reverse, a neutral range for cutting off the driving force from the engine to a neutral state, a drive range for traveling, and the like. There is. When the shift lever is operated to the parking range, the output shaft of the automatic transmission is automatically locked.

By the way, the parking mechanism of the belt type transmission in such an automatic transmission is constructed as follows, for example. That is, a secondary shaft having a driven pulley attached thereto is provided with a parking gear that rotates integrally with the secondary shaft. When the shift lever is operated to the parking range position, the parking sprag (parking pole) operates in conjunction with the shift lever. It is configured to mesh with the parking gear. In addition,
Patent Document 1 discloses a parking structure for an automatic transmission in which a space in a transmission housing is effectively used and assembly work can be easily performed.

[Patent Document 1] Japanese Unexamined Patent Publication No. 5-280607

[0005]

However, such a conventional technique has the following problems. That is, a hydraulic mechanism for changing the groove width of the driven pulley is provided near the driven pulley, and the structure near the driven pulley is complicated and large. Therefore, if the parking gear is arranged at such a position, it may interfere with the driven pulley or the hydraulic mechanism, and it is difficult to dispose the parking gear. In addition, there is a problem that trying to avoid such interference causes a further increase in size and an increase in weight and cost.

Further, when the parking gear is arranged on the secondary shaft, there is a problem that the handling of the parking cable becomes very difficult when the interference with the auxiliary machine is taken into consideration.

Further, in the technique disclosed in Patent Document 1, even if the interference between the parking gear and the peripheral mechanism is avoided, the miniaturization of the parking mechanism is not sufficient.
There is a demand for further downsizing of the parking mechanism, and thus of the entire transmission. The present invention has been devised in view of such a problem, and provides a belt-type transmission for a vehicle, which can further reduce the size of the transmission while avoiding the interference between the parking gear and its peripheral mechanism. The purpose is to do.

[0008]

Therefore, a vehicle belt type transmission according to a first aspect of the present invention includes a drive pulley arranged on a first shaft to which a driving force is input, and the first pulley. And a driven pulley to which the driving force of the driving pulley is transmitted via an endless belt which is arranged on a second shaft arranged in parallel with the shaft and is wound around the driving pulley. In a belt type transmission for a vehicle, which changes a gear ratio between the driving pulley and the driven pulley by changing a groove width of the pulley, the belt type transmission for a vehicle is disposed on the second shaft and is integrated with the second shaft. And a driven gear that rotates with respect to the second pulley and is capable of suppressing rotation of the second shaft by meshing with a parking sprag attached to the housing.
A fixed pulley that is immovable in the axial direction with respect to the shaft, a movable pulley that is movable in the axial direction, and a hydraulic piston mechanism that drives the movable pulley in the axial direction. A piston that is arranged immovably in the axial direction on the second shaft and forms a hydraulic chamber between the movable pulley and the piston, and the movable pulley is fixed between the movable pulley and the piston. A return spring that biases the pulley side and a balance member that is fixed to the movable pulley and forms a centrifugal balance chamber between the piston and the piston are provided. The piston supports the return spring in the axial direction. The balance member is formed along the shape of the piston, and the parking gear has a support portion and a small diameter portion formed on the axially opposite side of the movable pulley with the support portion interposed therebetween. Adjacent to the balance member And an outer peripheral end portion having a tooth portion that meshes with the parking sprag is disposed at a position axially opposed to the support portion of the piston, and the balance member and the small diameter portion are prevented from interfering with each other. In order to avoid it, it is characterized in that it is formed so as to curve toward the balance member side.

As described above, since the small diameter portion is formed on the piston adjacent to the support portion of the return spring and the balance member is formed along the shape of the piston, the hydraulic piston mechanism can be made compact. . Further, since the parking gear arranged adjacent to the balance member is formed so that the outer peripheral end faces the support portion and is curved toward the balance member side so as not to interfere with the small diameter portion, The parking gear can be compactly arranged. In addition, in the vehicle belt type transmission of the present invention described in claim 2, in addition to the configuration described in claim 1, the piston has a large diameter portion on the movable pulley side in the axial direction of the support portion. However, the supporting portion is characterized by being formed by a step surface between the large diameter portion and the small diameter portion. As described above, since the support portion is formed by the step surface between the large diameter portion and the small diameter portion and the outer peripheral end portion of the parking gear is arranged to face the support portion, the parking gear should be compactly arranged. You can

Further, in the vehicle belt type transmission of the present invention as defined in claim 3, the inner peripheral end portion of the balance member forms a supply port of hydraulic oil to the centrifugal balance chamber, and the parking gear. Is formed with an oil passage for supplying hydraulic oil to the oil supply port. In this way, since the oil passage for supplying the hydraulic oil to the hydraulic oil supply port of the centrifugal balance chamber is formed in the parking gear, the hydraulic oil can be surely supplied to the centrifugal balance chamber.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A vehicle belt-type transmission according to 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 structure thereof, FIG. 2 is an enlarged view of the speed change mechanism portion, and FIGS. 3 to 6 are views for explaining the parking mechanism.

Now, as shown in FIG. 1, the transmission is provided with a casing 1 for accommodating an internal mechanism. The casing 1 is composed of a torque converter housing 3 and a transmission case 5 and can be divided into two parts. The casing 1 is fastened with a bolt 1a. Further, the torque converter housing 3 includes a casing 1
A partition wall 3a for partitioning the inner space of the into two is integrally formed, and the torque converter housing (housing member) 3 and the transmission case 5 are configured to be divided on one plane.

Inside the casing 1, the first shaft 2 and the second shaft 2 are provided.
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 through the secondary shaft 4 and the transfer shaft 6 to a differential (differential mechanism). Two
7 and the left and right output shafts (drive shafts) 24
Are being 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, and a driven pulley (driven) is provided on the secondary shaft 4. A pulley) 18, a parking gear 16, a transfer drive gear 14, etc. are provided. 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 is a final gear 26 provided on an output shaft (drive shaft) 24.
Meshes with.

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

The input shaft 2A is pivotally supported via a reaction shaft 36a, a reaction shaft support 36b and the like. By the way, as shown in FIG. 2, the torque converter 8 is housed in the torque converter housing 3 described above, 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 is transmitted.

The torque converter 8 is constructed in the same manner as a normal automatic transmission, and includes a pump 8a, a turbine 8b and a stator 8c.
It has The pump 8a is connected to the engine crankshaft via a drive plate 8d,
When this pump 8a is rotationally driven, the torque converter 8
The rotational energy of the pump 8a is transmitted to the turbine 8b via the hydraulic oil therein. Further, the turbine 8b is spline-coupled to the input shaft 2A via the turbine hub 8e, and the input shaft 2A is rotationally driven by the rotational driving force transmitted to the turbine 8b. The torque converter 8 has a direct coupling (lock-up) mechanism that directly transmits the driving force from the drive plate 8d to the turbine 8b.

The rear side of the torque converter 8 (see FIG. 2)
A forward / reverse switching mechanism 10 is provided on the left side). The forward / reverse switching mechanism 10 is provided with the input shaft 2
This is for switching the rotation direction of the rotational driving force transmitted from A to the primary shaft 2B or for cutting 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 housed in the cylindrical case 28. Etc. are provided. The cylindrical case 28 is attached to the partition wall 3a of the torque converter housing 3 with bolts 28a, and the rigidity of the entire transmission is improved.

The planetary gear mechanism 30 is constructed as a double pinion type planetary gear mechanism having two pinion gears, and includes a sun gear 30a, a first pinion gear 30b, and
It is composed of a second pinion gear 30c, a planetary carrier 30d and an annulus gear (ring gear) 30e. In addition, as shown in FIG. 2, in this embodiment, the sun gear 30a is integrally formed with the input shaft 2A. Further, the first pinion gear 30b and the second pinion gear 30c are axially supported by the planetary carrier 30d while meshing with each other, the first pinion gear 30b is the sun gear 30a, and the second pinion gear 30c is the annulus gear 3.
It meshes with 0e.

The planetary carrier 30d has a shaft support portion 30d-1 provided at the end of the drive pulley 12 side.
And the shaft support portion 30d-1 has the drive pulley 12
And is splined. Also, the above-mentioned brake 3
4 is the outer peripheral side of the annulus gear 30e and the cylindrical case 2
It is arranged between the inner peripheral side of 8 and the annulus gear 3
It is provided to regulate the rotation of 0e. The brake 34 includes a brake disc 34 that meshes with the annulus gear 30e and rotates integrally with the annulus gear 30e.
a and a cylindrical case 28 that meshes with the cylindrical case 28.
And a plurality of brake plates 34b fixed in the rotational direction with respect to these plates 34a, 3b.
4b are arranged alternately. Further, a cylindrical brake piston 34c is provided at an end of the cylindrical case 28 on the drive pulley 12 side, and hydraulic oil is stored in 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 to come into contact with the brake plate 34b.

Then, in this way, the brake piston 34
When c is driven, the brake plate 34b is pressed by the brake piston 34c, and the rotation of the annulus gear 30e is restricted by the frictional force between each plate 34a and each disk 34b. On the other hand, the clutch 32 is provided to regulate the relative rotation between the sun gear 30a and the planetary carrier 30d, and like the brake 34 described above, the plurality of clutch disks 32a and the plurality of clutch plates 32b are alternately arranged. It is arranged. Here, the clutch disc 32
"a" meshes with a spline of a cylindrical portion extending in the axial direction from the body of the planetary carrier 30d, so that the clutch disc 32a and the planetary carrier 30d rotate together.

The clutch plate 32b meshes with the spline of the outer cylindrical portion of the clutch retainer 32f shown in FIG. 2 and rotates together with the clutch retainer 32f. Here, the clutch retainer 32
f is a member that is slidably supported 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. There is.

A clutch actuating piston 32c is disposed at the end of the clutch retainer 32f.
When hydraulic oil is supplied to the 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 to come into contact with the clutch plate 32b.

Then, in this way, the clutch piston 32
When c is driven, the clutch plate 32b is pressed by the clutch piston 32c, and each plate 32a,
Relative rotation between the sun gear 30a and the planetary carrier 30d is restricted by the frictional force between the sun gears 32b, so that 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 30a
The rotational driving force input to a is directly transmitted to the primary shaft 2B of the drive pulley 12. 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 the rotational driving force is input to the sun gear 30a, the first pinion gear 30b and the second pinion gear 30c revolve while revolving in the direction opposite to the rotation direction of the sun gear 30a, whereby the pinion carrier 30d is rotated. Mo Sun Gear 3
It rotates in the opposite direction of 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 the neutral state is established. Thus, the forward / reverse switching mechanism 10
Then, by controlling the operation of the clutch 32 and the brake 34, switching control of the rotational direction transmitted to the drive pulley 12 is performed.

In this embodiment, the forward / reverse switching mechanism 1
Although the double pinion type planetary gear mechanism 30 is used for 0, the forward / reverse switching mechanism 10 is not limited to such a mechanism, and may be a single pinion type planetary gear mechanism or a synchromesh type. It may be a switching mechanism. Now, at the 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 the power transmission surface 12a-having a substantially conical shape is formed on the surfaces of the pulleys 12a and 12b that face each other.
1, 12b-1 are formed. Then, the pulleys 12a, 12b-1 and 12b-1 are connected by the power transmission surfaces 12a-1, 12b-1.
A V-shaped groove 12c is formed between the 12b.

Further, one end (the right end in FIG. 2) of the primary shaft 2B has a shaft support portion 30 of the planetary carrier 30d.
It is pivotally supported on the end of the cylindrical case 28 via d-1 and the bearing 40, and the other end (the left end in FIG. 2) is pivotally supported on the transmission case 5 via the bearing 42. In this device, as described above, the bearing distance (or bearing span, see FIG. 1) of the primary shaft 2B can be shortened by pivotally supporting the primary shaft 2B on the end of the cylindrical case 28. Therefore, 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 due to the steel belt (endless belt) 44 described later, but by shortening the bearing span as described above, The flexural rigidity with respect to various tensions can be improved.

By the way, in the present transmission, the primary shaft 2B and the planetary carrier 30d are spline-coupled to each other in the vicinity of the position where the bearing 40 of the cylindrical case 28 is disposed. That is, as shown in FIG. 2, at the position where the bearing 40 is arranged, the outer peripheral portion of the primary shaft 2B and the inner peripheral portion of the shaft supporting portion 30d-1 of the planetary carrier 30d mesh with each other by a spline, and further the shaft supporting 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 pivotally supported by the transmission case 5 via a bearing 42. Then, in this way, on the inner peripheral side of the bearing 40, the primary shaft 2B
With the configuration in which the planetary carrier 30d and the planetary carrier 30d are spline-coupled, the forward / reverse switching mechanism 10 and the drive pulley 12 can be configured with high rigidity and compactness. Further, as will be described in detail later, with such a structure, the assembly itself of the transmission can be facilitated.

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 also configured similarly to the drive pulley 12, and includes a fixed pulley 18a and a movable pulley 18b.
Further, substantially conical power transmission surfaces 18a-1 and 18b-1 are formed on the surfaces of the pulleys 18a and 18b that face each other, 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 rotationally driven through 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 on the driven pulley 18 side. Is the steel belt 44 and the power transmission surface 18a-
The driven pulley 1 is driven by the frictional force between the driven pulley 1 and 18b-1.
8 is rotationally driven.

The distance between the fixed pulleys 12a, 18a and the movable pulleys 12b, 18b, that is, the groove 12
The gear ratio can be changed by changing the widths of c and 18c. Therefore, the drive pulley 12
The movable pulley 12b by driving the movable pulley 12b.
A hydraulic piston mechanism 60 for changing the width dimension of the groove 12c is attached.

The drive pulley 12 and the hydraulic piston mechanism 60 will now be described. The movable pulley 12b
Is provided on the primary shaft 2B integrally formed with the fixed pulley 12a via a ball spline mechanism 46. The ball spline mechanism 46 restricts the movable pulley 12b from rotating relative to the primary shaft 2B. , Is provided so as to be movable in the axial direction.

On the other end side (left end in FIG. 2) of the primary shaft 2B, a cylindrical wall portion 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 arranged in the space formed by such a cylinder portion 48 and the movable pulley 12b.
0 and the cylinder portion 48 form a hydraulic chamber 54, and the piston 52 and the movable pulley 12b form a hydraulic chamber 56.

Here, the piston 50 is the movable pulley 12
It is in contact with the shaft end portion of b, and its relative movement in the axial direction with respect to the movable pulley 12b is restricted. The piston 52 is in contact with the tip end of the wall portion 48 a of the cylinder portion 48, and its relative movement in the axial direction with respect to the cylinder portion 48 is restricted. In addition, a seal member is interposed between the piston 50 and the cylinder portion 48 and between the piston 52 and the movable pulley 12b, respectively, to maintain the liquid tightness of the hydraulic chambers 54 and 56. .

Further, hydraulic oil is supplied to these hydraulic chambers 54 and 56 simultaneously by a 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 the hydraulic oil is supplied to the hydraulic chamber 56, the piston 52 is pressed leftward in the drawing, but the piston 52 has its axial position regulated by the wall portion 48a of the cylinder portion 48. , This reaction force causes the movable pulley 1
2b is driven to the right side 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. This is because a large force is required when narrowing (when driving the movable pulley 12b to the right in the figure). For this purpose, it is possible to increase the pressure of the hydraulic oil supplied, but by using the hydraulic piston mechanism 60 of the double piston as described above, the pressure receiving area of the hydraulic oil is limited in a limited space. Can be approximately doubled, and a large force can be efficiently obtained.

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

The rotational driving force input 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 a fixed pulley 18 of the driven pulley 18.
It is formed integrally with a, one end (the right end in the drawing) of which is supported by the torque converter housing 3 via a bearing 64, and the other end (the left end of the drawing) is supported by the transmission case 5 via a bearing 66. There is.

Further, 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 via the hydraulic oil supply path 5a formed on the transmission case 5 side. Further, as shown in FIG. 2, in the driven pulley 18, the drive pulley 12 described above is used.
Similarly, the movable pulley 18b is provided on the secondary shaft 4 via the ball spline mechanism 68,
The ball spline mechanism 68 restricts 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.

Further, the driven pulley 18 is provided with a hydraulic piston mechanism 62 for axially driving the movable pulley 18b 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 the direction opposite to the power transmission surface 18b-1 is formed. Further, a piston (secondary piston) 72 is provided on the inner peripheral side of the cylindrical wall portion 70, and the outer peripheral edge portion 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 portion 70 and the secondary piston 72.
The secondary piston 72 is fixed in the axial direction and the rotation direction with respect to the secondary shaft 4, and a return spring 76 that comes into contact with the secondary piston 72 and the movable pulley 18b is disposed in the hydraulic chamber 74. There is. The secondary piston 72 and the movable pulley 1
A seal member is interposed between the hydraulic chamber 74 and 8b, whereby the liquid tightness of the hydraulic chamber 74 is maintained.

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 side in the figure. . Then, due to this urging force, a desired frictional force is generated between the power transmission surfaces 18a-1 and 18b-1 and the steel belt 44, and a certain degree of clamping force (clamping force) is generated, and the driven pulley 1
8 is driven to rotate without slipping. Also, as shown, the secondary piston 72
Is provided with a small diameter portion 72a and a large diameter portion 72c, and the step surface between the small diameter portion 72a and the large diameter portion 72c
A support portion 72b that supports the return spring 76 in the axial direction is formed. Here, the large diameter portion 72c is formed on the movable pulley side of the secondary piston 72, and the end portion of the large diameter portion 72c has the secondary piston 72c.
The outer peripheral edge portion of the cylindrical wall portion 70 contacts the inner peripheral surface of the cylindrical wall portion 70. Further, the small diameter portion 72a is formed on the axially opposite side of the movable pulley with the support portion 72b interposed therebetween, and the end portion of the small diameter portion 72a is fixed to the secondary shaft 4.

Next, the operation during 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 movable pulley 18b is driven to the left side in the figure by supplying hydraulic oil to the hydraulic chamber 74 via the hydraulic oil supply oil passages 5a and 4a. That is, the width dimension of the groove 18c of the driven pulley 18 is narrowed, and the turning radius of the steel belt 44 is increased. That is, since the gear ratio of the pulley is: gear ratio = (belt rotation radius of driven pulley 18 side) / (belt rotation radius of drive pulley 12 side) (1), the gear ratio is large, That is, it becomes the low speed side.

Also during the shifting, the hydraulic chambers 54 and 56 on the drive pulley 12 side and the hydraulic chamber 78 on the driven pulley 18 side.
Appropriate hydraulic oil also acts on the movable pulleys 12b and 18b.
Due to the urging force of the drive pulley 12, the desired frictional force is generated between the power transmission surfaces 12a-1 and 12b-1 and the power transmission surfaces 18a-1 and 18b-1 and the steel belt 44.
It is possible to transmit the driving force from the driven pulley 18 to the driven pulley 18 at a low speed.

When the gear ratio is changed to the high speed side, hydraulic oil is supplied to the hydraulic chambers 54 and 56 on the drive pulley 12 side, whereby the movable pulley 12b is driven rightward in the drawing, The width of the groove 12c becomes narrower, and the radius of rotation of the steel belt 44 on the drive pulley 12 side becomes larger.
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 to widen the groove 18c and reduce the turning radius of the steel belt 44. . Therefore, the gear ratio becomes smaller according to the above formula (1), and the speed is higher.

Further, the hydraulic chamber 5 on the side of the drive pulley 12
4, 56 and the hydraulic chamber 74 on the side of the driven pulley 18 also act on the movable pulleys 12b, 1b.
A biasing force is generated in 8b, and power transmission surfaces 12a-1 and 12b
-1, a desired frictional force is generated between the power transmission surfaces 18a-1 and 18b-1 and 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. .

By the way, when the secondary shaft 4 rotates at a high speed in a state where the hydraulic oil is supplied to the hydraulic chamber 74 or remains in the hydraulic chamber 74, a large centrifugal force acts on the hydraulic oil in the hydraulic chamber 74. Such centrifugal force is proportional to the square of the distance from the center of rotation and acts not only in the radial direction of rotation but also in all directions of the hydraulic chamber 74. Therefore,
When the hydraulic oil is present in the hydraulic chamber 74, when the secondary shaft 4 rotates, particularly when the secondary shaft 4 rotates at high speed, the hydraulic chamber 74 has a high pressure and a force is generated to urge the movable pulley 18b to the left side in the drawing. As a result, a clamping force greater than the desired clamping force is generated. In this case, a desired gear ratio may not be achieved, or wear may occur between the driving force transmission surfaces 18a-1, 18b-1 and the steel belt 44.

Therefore, in the belt type transmission for this vehicle,
A centrifugal balance chamber (centrifugal hydraulic chamber) 78 is provided outside the hydraulic chamber 74.
Is provided, and the hydraulic pressure due to such centrifugal force is canceled. That is, as shown in FIG. 2, the hydraulic piston mechanism 62 is provided with a balancing cap (balance member) 80 which covers the cylindrical wall portion 70 and the secondary piston 72 and is formed along the shape of the secondary piston 72. The balancing cap 80 and the secondary piston 72 form a centrifugal balance chamber 78.

The balancing cap 80 is fixed to the cylindrical wall portion 70, and its inner peripheral end portion is formed as a supply port of hydraulic oil to the centrifugal balance chamber 78.
Further, the centrifugal balance chamber 78 is adapted to be supplied with hydraulic oil through the holes 4b and 4c provided in the secondary shaft 4 and the hole (oil passage) 16d provided in the parking gear 16. There is. Therefore, when the secondary shaft 4 rotates, particularly when rotating at high speed, centrifugal force generates a high pressure of the hydraulic oil in the hydraulic chamber 74, particularly on the outer peripheral side, which causes a force to expand the volume of the hydraulic chamber 74.
At this time, the hydraulic oil in the centrifugal balance chamber 78 also becomes high pressure due to the centrifugal force at the same time, and a force to expand 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) are offset to drive the movable pulley 18b. That power is cancelled.

On the other hand, on the secondary shaft 4, adjacent to the hydraulic piston mechanism 62, the parking gear 16 is provided.
And a transfer drive gear 14.
Both of these gears 16 and 14 are spline-coupled to the secondary shaft 4,
It is configured to rotate integrally with. Among these, as shown in FIG. 1, the transfer drive gear 14 meshes with a transfer driven gear 20 that is spline-coupled to the transfer shaft 6, and the transfer drive gear 14 and the transfer driven gear 20 cause the secondary shaft 4 to move. The rotational driving force is reduced and transmitted to the transfer shaft 6.

Further, as shown in FIG. 1, the transfer shaft 6 has a bearing 9 at one end (right end in the drawing) side.
Is supported by the torque converter housing 3 via 0,
The other end (the left end in the drawing) is supported by the transmission case 5 via a bearing 92. Of these, the bearing 90 is directly attached to the torque converter housing 3. On the other hand, the bearing 92 is attached to a bearing retainer 94 as shown in FIG. 1, and the bearing retainer 94 is attached to the transmission case 5 with a bolt 96.

A final drive pinion gear 22 is integrally formed on the transfer shaft 6, 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.

By the way, the above-mentioned parking gear 16 is
This is for restraining the rotation of the secondary shaft 4 when the gear shift lever (not shown) is operated to the parking range position (P position), and is provided for surely stopping the vehicle. Now, the main part of the vehicle belt transmission of the present invention will be described. As shown in FIGS. 2 and 4, in the present device, the parking gear 16 is disposed adjacent to the balancing cap 80. Cage, tooth portion 16b that meshes with the parking sprag 17
The outer peripheral end portion of the parking gear 16 having the is disposed so as to face the support portion 72b of the secondary piston 72 in the axial direction. A web 16a of the parking gear 16 (that is, a portion other than the tooth portion 16b of the parking gear 16) is formed to be curved toward the balancing cap 80 and the small diameter portion 72a. That is, as shown in FIG. 2, the web 1 of the parking gear 16 is
6a is formed so as to be curved so as to open to the driven pulley 18 side. As a result, the parking gear 16 is formed with an annular recess 16c.

This is for avoiding interference with the balancing cap 80 and interference with the torque converter housing (housing member) 3.
That is, as described above, on the secondary shaft 4, the hydraulic piston mechanism 6 is provided adjacent to the driven pulley 18.
2 is provided, and the hydraulic piston mechanism 62 includes
A balancing cap (balance member) 80 that forms a centrifugal balance chamber (centrifugal hydraulic chamber) 78 is provided.
Since the balancing cap 80 moves in the axial direction integrally with the movable pulley 18b, the parking gear 16 adjacent to the balancing cap 80 needs to be arranged so as not to interfere with the balancing cap 80.

In order to avoid such interference, a sufficient clearance may be provided between the balancing cap 80 and the parking gear 16, but the transfer drive gear other than the parking gear 16 may be provided on the secondary shaft 4. Since 14 is provided and the converter housing 3 is also close to it, it is difficult to secure sufficient space.

That is, if an attempt is made to secure a sufficient clearance between the parking gear 16 and the balancing cap 80, the axial length of the secondary shaft 4 will increase and the transmission will become large. On the other hand, if an attempt is made to secure a sufficient clearance between the parking gear 16 and the balancing cap 80 without changing the axial length of the secondary shaft 4, the parking gear 16 and the transfer drive gear 14 will interfere with the torque converter housing 3. However, if it is attempted to avoid such interference with the torque converter housing 3, the torque converter housing 3 will be upsized and the weight will be increased accordingly.

Therefore, in the vehicle belt type transmission of the present invention, as shown in FIG. 2 and FIG.
The center side of the web 16a is formed so as to be displaced in the direction opposite to the driven pulley 18 with respect to the tooth surface 16b, and the recess 16c is formed on the driven pulley 18 side of the parking gear 16.
Is provided. Specifically, parking gear 1
The cross-sectional shape of 6 is formed in a substantially cap shape so that the balancing cap 80 side is opened.

Thus, it is possible to avoid the interference between the balancing cap 80 and the parking gear 16 while arranging the driven pulley 18 and the parking gear 16 coaxially and close to each other. That is, even when the movable pulley 18b is driven to the right in FIGS. 2 and 4, the tip of the balancing cap 80 moves into the recess 16c of the web 16a of the parking gear 16, so The interference with the balancing cap 80 can be reliably avoided.

Further, in the cross section shown in FIG. 2, the web 16a of the parking gear 16 is formed so as to be displaced along the torque converter housing 3 with respect to the tooth surface 16b. Interference can also be avoided. By the way, as shown in FIG.
As shown in FIG. 6, a parking mechanism 15 is provided.

As shown in FIGS. 5 and 6, the parking mechanism 15 mainly includes a parking gear 16, a parking sprag 17, a shift cable 84, a manual control lever 85, a detent plate 86, a parking roller support 87 and a parking rod. It consists of 88 mag. Of these, one end of the shift cable 84 is connected to a gear shift lever (not shown), and the other end of the shift cable 84 is connected to a manual control lever 85. Also, the manual control lever 8
A detent plate 86 is attached to 5.
As a result, when the shift lever is operated, the operating force is transmitted to the detent plate 86 via the shift cable 84 and the manual control lever 85, and the detent plate 86 is rotated. In addition,
In FIG. 6, the shift cable 84, the manual control lever 85, and the parking gear 16 are omitted.

Further, the detent plate 86 has a structure shown in FIG.
~ A parking rod 88 as shown in Fig. 6 is connected. As shown in FIG. 5, two rollers 88a and 88b are provided in the vertical direction at the tip of the parking rod 88, and the lower roller 88b contacts a guide portion 87a formed on the parking roller support 87. Touching.

On the other hand, as shown in FIGS. 3 and 5, a parking sprag 17 is provided above the parking gear 16, and the parking sprag 17 is provided with a claw portion 17a for engaging with the parking gear 16. Has been formed. Further, as shown in FIG.
Is rotatably supported by a shaft 33c between a flange portion 28b formed on the cylindrical case 28 and the converter housing 3. Further, a return spring 17b is interposed at the center of rotation, and the parking sprag 17 is counterclockwise in FIGS. 3 and 5 by the urging force of the return spring 17b, that is, the claw portion 17a.
Is urged in a direction away from the parking gear 16.

Further, as shown in FIG. 5, a shaft 33b is provided on the rear end side (left side in the figure) of the parking sprag 17, and normally, as shown in FIG. By contacting the shaft 33b, the rotational position of the parking sprag 17 is regulated. Also, the parking roller support 87
As shown in FIGS. 4 and 6, is mounted between the cylindrical case 28 and the converter housing 3 via shafts 33a and 33b. That is, as shown in FIG. 6, holes 29a, 29b, 29c are formed in the flange 28b of the cylindrical case 28, and the converter housing 3 has the holes 29a, 2b.
Holes 31a, 31b, 3 are provided at opposite positions of 9b, 29c.
1c is provided. The parking roller support 87 is supported by the shafts 33a and 33b, and both ends of the one shaft 33a have holes 29a and 31a.
The shaft 33b is supported by a, and the other end of the other shaft 33b has a hole 2
It is adapted to be supported by 9b and 31b.
The holes 29c and 31c are holes for supporting the shaft 33c.

In such a parking mechanism 15, when the shift lever is operated to the parking range position, the detent plate 86 is rotationally driven via the shift cable 84 and the manual control lever 85, and in response to this, parking is performed. The rod 88 advances.
At this time, the roller 88b below the parking rod 88
Moves forward along the guide portion 87a of the parking roller support 87. Then, when the upper roller 88a moves forward while contacting the parking sprag 17, as shown in FIG. 3, the parking sprag 17 is rotationally driven in the clockwise direction in the figure against the biasing force of the return spring 17b, and the pawl is moved. The portion 17a meshes with the parking gear 16 and the rotation of the secondary shaft 4 is restricted. In FIG. 4, the parking sprag 17 has the parking gear 1.
6 is a top view in a state in which it is meshed with 6; FIG.

When the parking rod operates in the direction in which the parking sprag 17 is bitten into the parking gear 16 (when it is shifted to the P range), the rotational force of the detent plate 86 causes the parking rod retainer 88 to rotate.
d, transmitted to the parking rod 88f via the parking rod spring 88c. Therefore, the claws 17 a of the parking sprag 17 are connected to the groove 1 of the parking gear 16.
6c does not match, and the claw 17a has the tooth 1 of the parking gear 16.
When it comes into contact with 6b and stops, the parking rod spring 88c is in a compressed state. When the tire slightly rotates from this state and the parking gear 16 rotates accordingly and the claw 17a of the parking sprag 17 matches the groove 16c of the parking gear 16, the parking sprag 17 is biased by the parking rod spring 88c. Meshes with the parking gear 16, and the parking gear 16 is locked.

Further, when the shift lever is operated to a position other than the parking range position, the parking rod 8 is reversed, contrary to the above.
When 8 is retracted, the parking sprag 17 is rotationally driven in the counterclockwise direction in the drawing by the urging force of the return spring 17b, and as shown in FIG.
Is disengaged from the teeth of the parking gear 16. In FIG. 6, the parking sprag 17 is the parking gear 1.
6 is a top view in a state of being separated from 6, and is a view in which a part is broken. FIG. Further, at this time, the position of the parking sprag 17 is regulated by the end of the parking sprag 17 contacting the shaft 33b.

The parking mechanism 15 as described above is provided between the cylindrical case 28 and the converter housing 3, and the web 16a of the parking gear 16 is opposite to the tooth surface 16b from the driven pulley 18 as described above. By providing the concave portion 16c so as to be displaced in the direction, the step between the tooth surface 16b of the parking gear 16 and the mounting surface of the parking roller support 87 can be almost eliminated, and as shown in FIG. It becomes possible to form the shape of 17 into a substantially flat shape. And in this way parking sprag 1
By forming the shape of 7 substantially flat, it becomes easy to secure the position where the parking sprag 17 is provided, and
There is an advantage that the claw portion 17a of the parking sprag 17 and the parking gear 16 are surely engaged with each other.

That is, when the parking sprag 17 is formed by being greatly bent, the parking sprag 1
Considering the operation of No. 7, a correspondingly large space is required in the vicinity of the position where the parking sprag 17 is provided, and the parking mechanism 15 and the transmission itself inevitably become large. On the other hand, in this device, since the parking sprag 17 can be formed in a substantially flat shape as described above, the disposition position of the parking sprag 17 in the casing 1 of the complicated transmission can be relatively easily performed. It can be secured.

Further, by providing the parking mechanism 15 between the cylindrical case 28 and the converter housing 3 and disposing the parking mechanism 15 and the parking gear 16 in substantially the same plane, the parking mechanism 15 can be made lightweight and compact. Therefore, the arrangement itself in the casing 1 is facilitated. Further, this also enables the transmission main body to be downsized.

Since the vehicle belt-type transmission according to the 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. It In addition, the forward / reverse switching mechanism 1
At 0, the drive pulley 12 is switched between normal rotation, reverse rotation, and neutral by controlling the operation of the clutch 32 and the brake 34. Then, the rotational driving force input to the drive pulley 12 is transmitted to the driven pulley 18 via the steel belt 44.

On the other hand, 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. Then, the rotational driving force of the secondary shaft 4 is reduced by the transfer drive gear 14 and the transfer driven gear 20, and is transmitted to the transfer shaft 6. Also,
The rotational driving force input to the transfer shaft 6 is output to the left and right drive shafts 24 via the final drive pinion gear 22 and the final gear 26.

Further, the speed ratio between the drive pulley 12 and the driven pulley 18 is changed by controlling the hydraulic oil supply state of the hydraulic piston mechanisms 60 and 62 to move the movable pulleys 12b and 18c in the axial direction. It On the other hand, in the vehicle belt type transmission of the present invention, as shown in FIGS. 2 and 4, the center side of the web 16a of the parking gear 16 is displaced in the direction opposite to the driven pulley 18 with respect to the tooth surface 16b. Since the recess 16c is formed on the driven pulley 18 side of the parking gear 16,
It is possible to avoid the interference between the balancing cap 80 and the parking gear 16 while arranging the driven pulley 18 and the parking gear 16 coaxially and close to each other.

That is, the movable pulley 18b is shown in FIGS.
The balancing cap 80 approaches the parking gear 16 when driven in the middle right direction.
Since the tip of 0 moves into the recess 16c of the parking gear 16, the parking gear 16 and the balancing cap 8
It is possible to avoid the interference with 0. Further, the web 16a of the parking gear 16 is arranged along the torque converter housing 3 in the cross section shown in FIG.
Since it is formed so as to be displaced with respect to the tooth surface 16b, it is possible to reliably avoid interference between the parking gear 16 and the torque converter housing 3.

Next, the operation of the parking mechanism 15 will be described. When the gear shift lever (not shown) is operated to the parking range position, the detent plate 86 is rotationally driven via the shift cable 84 and the manual control lever 85, and the detent plate 86 is rotated. In response, the parking rod 88 moves forward. Then, as shown in FIGS. 3 and 4, the parking sprag 17 is rotationally driven in the clockwise direction in the figure against the biasing force of the return spring 17b. As a result, the claw portion 17a of the parking sprag 17 meshes with the parking gear 16 and the rotation of the secondary shaft 4 is restricted.

When the shift lever is operated to a position other than the parking range position, the parking rod 88 moves backward as shown in FIGS. 5 and 6, so that the parking sprag 17 is urged by the return spring 17b. It is rotationally driven in the counterclockwise direction, and the claw portion 17a is disengaged from the teeth of the parking gear 16. Further, at this time, the position of the parking sprag 17 is regulated by the end of the parking sprag 17 contacting the shaft 33b.

Now, the assembling of the parking mechanism 15 will be briefly described with reference to FIG. 6. First, the shafts 33a and 33b are passed through the parking roller support 87 and one end of each shaft 33a and 33b is attached to the torque converter housing 3. Insert into the holes 31a and 31b. Further, the shaft 33c is inserted into the hole 31c to attach the parking sprag 17 and the return spring 17b.

Next, the cylindrical case 28 accommodating the forward / reverse switching mechanism 10 is attached to the torque converter housing 3. At this time, the holes 29a, 2 of the flange 28b
The shafts 33a, 33b, 33c are inserted into 9b, 29c to fix the parking roller support 87. Further, in order to prevent the shaft 33c from coming off, the plate 89a is attached from the outside of the flange 28b, and the bolt 8
Fix with 9b. Further, the parking rod 88 is attached to the detent plate 86 attached to the valve body 98 side shown in FIG.

The parking mechanism 15 is provided between the cylindrical case 28 and the converter housing 3, and the web 16a of the parking gear 16 is formed so as to be displaced in the direction opposite to the driven pulley 18 with respect to the tooth surface 16b. By doing so, the parking sprag 17 can be formed into a substantially flat shape as shown in FIG.
There is an advantage that it is easy to secure the disposition position of the parking sprag 17.

Therefore, even in the casing 1 of the complicated transmission, the position of the parking sprag 17 can be secured relatively easily. Further, by providing the parking mechanism 15 between the cylindrical case 28 and the converter housing 3, the parking mechanism 1
It is possible to reduce the size and weight of the vehicle 5, and it is possible to easily arrange the parking mechanism 15 in the casing 1.

The vehicle belt type transmission of the present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the above-described embodiment, the example in which the torque converter is used as the power transmission means has been described, but the power transmission means is not limited to the torque converter, and a fluid coupling, an electromagnetic clutch, or the like may be used.

[0085]

As described above in detail, according to the vehicle belt type transmission of the present invention as defined in claim 1, a small diameter portion is formed in the piston adjacent to the support portion of the return spring, and the balance is achieved. Since the member is formed along the shape of the piston, the hydraulic piston mechanism can be made compact. Further, since the parking gear arranged adjacent to the balance member is formed so that the outer peripheral end faces the support portion and is curved toward the balance member side so as not to interfere with the small diameter portion, The parking gear can be compactly arranged.

Further, according to the vehicle belt type transmission of the present invention as defined in claim 2, the support portion is formed by the step surface between the large diameter portion and the small diameter portion, and the outer peripheral end portion of the parking gear is formed by the stepped surface. Since it is arranged so as to face the support portion, there is an advantage that the parking gear can be arranged compactly.

According to the vehicle belt type transmission of the present invention as defined in claim 3, since the oil passage for supplying the hydraulic oil to the hydraulic oil supply port of the centrifugal balance chamber is formed in the parking gear, the centrifugal balance is achieved. There is an advantage that the hydraulic oil can be reliably supplied to the chamber.

[Brief description of drawings]

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

FIG. 2 is an enlarged view showing a transmission mechanism portion in a vehicle belt type transmission apparatus according to an embodiment of the present invention.

FIG. 3 is a schematic side view showing a parking mechanism in the vehicle belt-type transmission according to the embodiment of the present invention, and is a view showing a state in which the parking mechanism is operated.

FIG. 4 is a schematic top view showing a parking mechanism in a vehicle belt type transmission as one embodiment of the present invention, and is a top view of FIG.

FIG. 5 is a schematic side view showing a parking mechanism in a vehicle belt type transmission as one embodiment of the present invention, and is a view showing a state in which the parking mechanism is released.

6 is a schematic top view showing a parking mechanism in a vehicle belt-type transmission according to an embodiment of the present invention, and is a top view of FIG.

[Explanation of symbols]

1 casing 2 Primary axis 2A input shaft (input shaft) 2B primary shaft 2C oil pump drive shaft 3 Torque converter housing 3a partition 3b Hole (support) 4 Second shaft (secondary shaft) 5 transmission case 6 Third axis (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 12c groove 13 Oil pump 14 Transfer drive gear 15 Parking mechanism 16 parking gear 16a web 16b tooth surface 16c recess 16d hole (oil passage) 17 parking sprags 17a Claw 17b Return spring 18 Driven pulley (driven pulley) 18a Fixed pulley 18b movable pulley 18a-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 28b Flange part 29a to 29c Holes 30 Planetary gear mechanism 30a Sun Gear 30b 1st pinion gear 30c Second pinion gear 30d planetary carrier 30d-1 Shaft support 30e Annulus gear (ring gear) 31a to 31c Holes 32 clutch 32a clutch disc 32b clutch plate 32c clutch piston 32d oil chamber 32e Return spring 32f clutch retainer 33a-33c shaft 34 Brake 34a brake disc 34b brake plate 34c brake piston 34d oil chamber 34e Return spring 36 Reaction shaft support 40, 42 bearing 44 Steel Belt (Endless Belt) 46 ball spline mechanism 48 Cylinder part 48a wall 50,52 piston 54,56 hydraulic chamber 60,62 Hydraulic piston mechanism 64 66 bearing 68 ball spline mechanism 70 Cylindrical wall 72 piston (secondary piston) 72a Small diameter part 72b support 72c Large diameter part 74 Hydraulic chamber 76 Return spring 78 Centrifugal balance chamber (centrifugal hydraulic chamber) 80 Balancing cap (balance member) 84 shift cable 85 Manual control lever 86 detent plate 87 Parking roller support 88 parking rod 88a, 88b rollers 89a plate 89b bolt 90,92 bearing 94 Bearing retainer 96 volts 98 valve body

Claims (3)

[Claims] 1. A drive pulley arranged on a first shaft to which a driving force is inputted, and a second shaft arranged side by side on the first shaft, and hung around the drive pulley. A driven pulley to which the driving force of the driving pulley is transmitted via an endless belt, and by changing the groove widths of the driving pulley and the driven pulley, the gear ratio between the driving pulley and the driven pulley is changed. In a belt type transmission for a vehicle to be changed, the second shaft is disposed on the second shaft to rotate integrally with the second shaft, and at the same time, to rotate the second shaft by meshing with a parking sprag attached to a housing. And a driven pulley that drives the movable pulley in the axial direction. The driven pulley includes a stationary pulley that is immovable in the axial direction with respect to the second shaft, a movable pulley that is movable in the axial direction, and a movable pulley. And a hydraulic piston mechanism for The pressure piston mechanism is disposed between the movable pulley and the piston, and a piston that is arranged immovably in the axial direction on the second shaft to form a hydraulic chamber between the piston and the movable pulley. A return spring that biases the movable pulley toward the fixed pulley, and a balance member that is fixed to the movable pulley and forms a centrifugal balance chamber between the piston and the return spring are provided. And a small diameter portion formed on the axially opposite side of the movable pulley with the support portion interposed therebetween, the balance member being formed along the shape of the piston, The parking gear is disposed adjacent to the balance member, and an outer peripheral end portion having a tooth portion meshing with the parking sprag is disposed at a position axially opposed to the support portion of the piston, The bar A belt type transmission for a vehicle, which is formed so as to be curved toward the piston so as to avoid interference with the lance member and the small diameter portion. 2. The piston has a large diameter portion on the side of the movable pulley in the axial direction of the support portion, and the support portion is formed by a step surface between the large diameter portion and the small diameter portion. The belt-type transmission for a vehicle according to claim 1, wherein: 3. The balance member has an inner peripheral end portion which forms a supply port of hydraulic oil to the centrifugal balance chamber, and the parking gear has an oil passage for supplying hydraulic oil to the oil supply port. The belt type speed change device for a vehicle according to claim 1 or 2, wherein the speed change device is formed.