JPH10184832A - V-belt type automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cooling performance and power transmitting performance of a driving flywheel in a V-belt type automatic transmission. SOLUTION: A V-belt type automatic transmission is provided with a driving shaft 42 provided with a driving flywheel 45 and a driving flywheel thrust generating mechanism 44, a driven shaft provided with a driven flywheel, and a V-belt 46, and on the driving shaft 42, a movable shave 81 and the thrust generating mechanism 44 are arranged apart in the axial direction. In this way, air flow around the movable sheave 81 is increased, so that cooling performance is improved. When the thrust generating mechanism 44 is stored inside a shaft case 27 while the driving flywheel 45 is arranged on the outside of the shaft case 27, the driving flywheel 45 is exposed to the outside, and cooling performance is improved further, and a life of the V-belt 46 can be prolonged. When the thrust generating mechanism 44 is sealed inside the shaft case 27 and oil lubrication is carried out inside the shaft case 27, rotation speed and transmission power can be increased, and at the same time, durability and a maintenance property of the thrust generating mechanism 44 can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a V-belt type automatic transmission, and more particularly to a V-belt type automatic transmission used for a power transmission device of a scooter type motorcycle.

[0002]

2. Description of the Related Art FIG. 5 shows a drive gear of a conventional V-belt type automatic transmission described in Japanese Patent Application Laid-Open No. 62-203887 (Japanese Patent Application No. 61-44359). Comprises a drive sheave 5 comprising a fixed sheave 2 fixed in the axial direction and a movable sheave 3 movable in the axial direction,
A drive sheave thrust generating mechanism 4 for converting the centrifugal force generated in the centrifugal weight into an axial thrust is provided on the back surface of the movable sheave 3, and a driven sheave (not shown) is provided with a driven sheave. A V-belt 6 is wound around the vehicle 5 and the driven vehicle, and a driving vehicle thrust generating mechanism 4 generates a vehicle adjusting thrust corresponding to the rotational speed of the vehicle driving vehicle, thereby performing power transmission and shifting. .

The driving wheel thrust generating mechanism 4 includes a rolling ball (centrifugal weight) that can move radially between a cam surface 7 formed on the back surface of the movable sheave 3 and a cam plate 8 fixed in the axial direction.
9, the rolling ball 9 moves radially outward due to centrifugal force, thereby pushing the movable sheave 3 toward the fixed sheave 2 and changing the effective winding diameter of the drive sheave 5 to change the speed. It is supposed to.

[0004] Rolling balls 9 are provided on the outer periphery of the movable sheave 3.
And a cover 10 that covers the cam plate 8 in a liquid-tight state is attached.
The inner peripheral end of the cover 10 is fixed to the drive shaft 1 by a disk-shaped holder, and lubricating oil such as grease is sealed in the cover 10.

As described above, in the device in which the drive sheave thrust generating mechanism 4 is mounted on the back of the movable sheave 3, the movable sheave 3
Since the volume of the space inside the cover 10 changes with the sliding in the axial direction, the cover 10 is formed of an elastic material such as rubber in order to always secure a constant amount of grease.

The drive sheave 5 and the drive sheave thrust generating mechanism 4 are disposed in a dry chamber completely separated from the oil chamber in the crankcase. Specifically, it is housed in a shaft case 11, which is an extension of the crankcase.

[0007]

As shown in FIG. 5, the movable sheave 3 is integrally provided with a drive wheel thrust generating mechanism 4 on the rear surface and the rear surface is covered by a rubber cover 10, so that the movable sheave 3 is extremely movable. This lowers the cooling performance of the sheave 3, thereby inhibiting the heat dissipation of the V-belt 6 sandwiched between the sheaves 3 and causing the V-belt 6 to wear early.

When the cover 10 made of an elastic material is mounted on the movable sheave 3, it is not suitable for high-speed rotation due to the strength of the material. In addition, when the transmission power increases, frictional heat increases due to an increase in transmission loss between the belt 6 and the movable sheave 3, and the heat resistance of the elastic cover is required to be improved. In addition to the labor involved, the cost of replacement parts also increases.

[0009]

The objects of the present invention are as follows. (1) Improve the cooling of the movable sheave, thereby increasing the heat dissipation of the V-belt.

(2) A structure capable of oil lubrication without encircling the drive wheel thrust generating mechanism portion with an elastic cover is provided, thereby improving durability and maintainability with respect to an increase in rotation speed or transmission power.

[0011]

In order to achieve the above object, an invention according to claim 1 of the present application is directed to a drive shaft provided with a drive sheave and a drive sheave thrust generating mechanism, and a driven sheave provided with a driven sheave. In a V-belt type automatic transmission including a shaft and a V-belt wound between the two wheels, the drive wheel on the drive shaft and the drive wheel thrust generating mechanism are arranged separately in the axial direction. It is characterized by having.

[0012] The invention according to claim 2 provides the V according to claim 1.
The belt type automatic transmission is characterized in that a drive sheave thrust generating mechanism is housed in a shaft case supporting a drive shaft, and the drive sheave is arranged outside the shaft case.

The invention according to claim 3 is the same as the invention according to claim 2,
The belt type automatic transmission is characterized in that the drive sheave thrust generating mechanism is sealed in the shaft case, and the drive sheave thrust generating mechanism is oil-lubricated in the shaft case.

[0014]

FIG. 1 is a left side view of a scooter-type motorcycle to which the present invention is applied. The vehicle body frame has a pair of left and right upper down tubes 20 and lower down tubes 21, respectively. 4 down tubes 2
Most of the engine 22 is housed in a space surrounded by 0 and 21. The engine 22 is disposed in a forwardly inclined position in which the cylinder center line is substantially horizontal, and a pair of right and left mounting brackets 23 is formed on the front, rear, and rear of the upper surface, respectively. It is attached to an engine mount formed on each cross member 25 via an elastic member. Engine 2
The second crankcase 26 integrally has a shaft case 27 extending rearward on the right side thereof.

A rear arm support shaft 32 is supported at the rear lower portion of the lower down tube 21 via a pair of left and right brackets 30, and the rear arm support shaft 32 has a rear arm 33.
Are rotatably fitted and supported. A rear end of the rear arm 33 supports a rear wheel 34 and is suspended by an upper frame via a rear cushion 35 so as to be vertically swingable.

FIG. 2 is a plan view of FIG.
A rotatable shaft 42 parallel to the crankshaft 41 is rotatably supported on the rear shaft case 27 so that the left and right widths of the right and left shafts fall within a space surrounded by the four down tubes 20 and 21. A centrifugal start clutch 43, a driving wheel thrust generating mechanism 44, and a driving wheel 45 of a V-belt type automatic transmission 47 are mounted. Rotating shaft 42 and crankshaft 41
Means a pair of sprockets 49 and 50 and a chain 52
The primary deceleration transmission mechanism 53 is interlocked and connected. Since the rotary shaft 42 serves as a drive shaft of the V-belt type automatic transmission 47 in the present invention, the “rotary shaft 42” is hereinafter referred to as a “drive shaft 42”.

The V-belt type automatic transmission 47 includes a drive shaft 42, a drive sheave 45, and a drive sheave thrust generating mechanism 44.
, A driven wheel 57, a cylindrical driven shaft 55 to which the driven wheel 57 is fixed, and a V-belt 46 wound between the wheels 45 and 57.

The driving sprocket gear 5 of the secondary reduction transmission mechanism 60 is mounted on the cylindrical driven shaft 55 together with the driven gear 57.
8 and the driving sprocket gear 58 is attached to the rear axle 3
6 is linked to a terminal sprocket gear 59 via a chain 61.

FIG. 3 is an enlarged partial view taken along the line III-III of FIG. 1. In the state of the solid line in front of the axis of the drive shaft 42, the effective winding diameter of the drive pulley 45 is minimum. The state, that is, the state in which the speed reduction ratio of the V-belt type automatic transmission 47 is the largest and the state is mainly at the time of low-speed traveling, and the front virtual line and the state on the rear side have the maximum effective winding diameter of the driving wheel 45. The state, that is, the state mainly at the time of high-speed running with the reduction ratio of the V-belt type automatic transmission 47 being the minimum is shown. Drive shaft 42
Is supported on the right end wall of the shaft case 27 via a bearing 62, and the left end portion is supported on the left end wall of the shaft case 27 via a movable sleeve 63 and a bearing 64, and extends to the left outside the shaft case. It is protruding. Shaft case 27 of drive shaft 42
The sprocket gear 50, the centrifugal start clutch 43, and the driving gear thrust generating mechanism 44 are arranged in the inner part in order from the right. The vehicle 45 is located. The sprocket gear 50 is rotatably supported on the drive shaft 42 via a bearing metal 74.

The centrifugal starting clutch 43 is fixed to a boss of the sprocket gear 50 and rotates integrally with the shoe holder 65.
A plurality of shoes 67 rotatably supported via support pins 66 parallel to the shaft, a hub 68 spline-fitted to the drive shaft 42 so as to be immovable in the axial and rotational directions, and the hub 68
And a drum 69 fixed to the drum. When the rotation speed of the shoe holder 65 on the driving side (drive side) becomes equal to or higher than a certain value, the shoe 67 expands radially outward due to centrifugal force, and presses against the inner peripheral surface of the drum 69. As a result, the rotational force of the sprocket gear 50 is
7, transmitted to the drive shaft 42 via the drum 69 and the hub 68.

The driving wheel thrust generating mechanism 44 includes a movable plate 73 having a plurality of pressure receiving rollers 72 and a plurality of cam weights 71. A plurality of pins 70 are provided on the end wall of the hub 68 along the circumferential direction.
The cam weights 71 are rotatably supported at 0. The movable plate 73 is spline-fitted to the drive shaft 42 so as to be movable in the axial direction, and is in contact with the movable sleeve 63 so as to move integrally therewith. Each of the pressure receiving rollers 72 is disposed at a position corresponding to each of the cam weights 71. The cam weight 71 is rotated leftward in the direction of arrow P with an increase in the rotation speed of the hub 68, and is pushed to the left to move. The plate 73 and the movable sleeve 63 move integrally to the left.

A seal 75 is fitted to the left side of the bearing 64 between the movable sleeve 63 and the inner peripheral hole of the left wall of the shaft case 27 to seal the inside of the shaft case 27.

The drive sheave 45 comprises a left fixed sheave 80 and a movable sheave 81 axially opposed thereto.
The fixed sheave 80 is fixed in the rotational direction by spline fitting to the left end of the drive shaft 42, and is also fixed in the axial direction by a washer 76 and a nut 77, while the movable sheave 81 is Step 63
Until locked at a, the sleeve 63 is screwed and integrated into the threaded portion at the left end. A cooling fan 92 is formed on the left end surface of the fixed sheave 80, and the cooling air is forcibly taken into the drive shed 45 through the air passage 91 of the fan cover 90.

The driving wheel thrust generating mechanism 4 in the shaft case 27
A lubricating oil pump (not shown) is provided at the right end of the drive shaft 42 as a mechanism for oil-lubricating the starting clutch 4 and the starting clutch 43.
And a lubricating oil chamber 85 connected to the
A lubrication passage 84 communicating with the clutch shaft is formed in the drive shaft core portion.
It communicates with a lubrication passage 87 for generating a drive wheel thrust at the far end (left end). The clutch lubrication passage 86 extends radially outward and opens into the drum 69 through an oil hole 88 in the hub 68 so that the inside of the drum 69 is forcibly lubricated and cooled. On the other hand, the lubrication passage 87 for generating a drive gear thrust extends radially outward and communicates with the inner circumferential annular gap 89 of the sleeve 63, and the left end of the annular gap 89 has an oil hole 90 of the sleeve 63. The lubrication of the bearing 64 is performed by communicating with the bearing 64 via the through hole. The right side of the annular gap 89 opens toward the roller 72 via the oil hole 92, and communicates with the right end edge of the sleeve 63 through the inner peripheral spline portion of the movable plate 73. 71 is lubricated.

FIG. 4 shows the driven sheave 57, which comprises a right fixed sheave 93 and a left movable sheave 94. The fixed sheave 93 is fixed to the cylindrical driven shaft 55 in the axial direction and the rotation direction. The movable sheave 94 has a cylindrical driven shaft 55
Are fixed by rivets or the like to a movable sleeve 95 that fits into the movable sleeve 95. The movable sleeve 95 has a plurality of cylindrical cam grooves 97 extending spirally in the axial direction. The cylindrical cam grooves 97 are slidable in the axial direction on roller pins 96 locked on the cylindrical driven shaft 55. , The driving force transmitted to the driven gear 57 acts on the cylindrical cam groove 97, and is converted into a force for pressing the movable sleeve 95 and the movable sheave 94 against the fixed sheave side. To the V-belt 46 sandwiched in between, a turning thrust according to the transmission power is applied. A cover 98 with a flange is fitted around the outer periphery of the movable sleeve 95, and a spring 100 is contracted between a right end flange portion of the cover 98 and a left spring receiver 99. And the movable sheave 94 is urged rightward with a constant spring force.

The operation of the power transmission device will be briefly described. When the engine is stopped or idling, the drive
5 and the like are in a state as shown on the front side of FIG. That is, the starting clutch 43 is disengaged, the cam weight 71 is closed toward the shaft center, the drive shed 45 opens between the sheaves 80 and 81 to the maximum, and the effective winding diameter is the minimum. . On the other hand, the driven gear 57 in FIG. 4 has the maximum effective winding diameter due to the elastic force of the spring 100. It is in a so-called low state.

When the rotation speed is increased to a certain value, the starting clutch 43 is connected, and the drive shaft 42, the sleeve 63, the movable plate 73, and the sheaves 80 and 81 rotate integrally.

As the rotation speed increases, the cam weight 71
Is expanded radially outward, and the movable plate 7
Press 3 to the left. Thereby, the movable plate 73, the sleeve 6
The effective winding diameter is enlarged by moving the sheave 3 and the movable sheave 81 integrally to the left and narrowing the space between the sheaves 80 and 81. Along with this, in the driven gear 57 in FIG. 4, the space between the sheaves 93 and 94 is widened by the belt 46 against the spring 100, and the effective winding diameter is reduced.

Explaining the cooling, the drive sheave 45 shown in FIG. 3 has both sheaves 80 and 81 arranged outside the shaft case 27, and the rear face of the movable sheave 81 is provided with a drive sheave thrust generating mechanism 44. Is separated from the belt in the axial direction and is exposed to the outside.
Even if high frictional heat is generated between
Heat can be dissipated efficiently. In addition, fixed sheave 8
Since the cooling fan 92 is provided in the unit 0, the heat radiation effect is improved.

In the shaft case 27, the lubricating oil supplied from the lubricating oil pump to the lubricating oil chamber 85 is supplied to the lubricating passage 84.
A part is released from the clutch lubrication passage 86 into the clutch drum 69 through the oil hole 88 to lubricate and cool the starting clutch 43, and the remainder is formed from the drive adjusting thrust generating lubrication passage 87 through the annular gap 89. And lubricates the bearing 64 through the oil hole 90 and is discharged to the outside from the oil hole 92 and the right end edge of the sleeve 63 to lubricate the pressure receiving roller 72 and the cam weight 71 of the driving gear thrust generating mechanism 44. And cool.

[0031]

[Other embodiments]

(1) A mechanism using a rolling ball or a rotation sensing unit may be separately provided as a drive adjusting thrust generating mechanism, and a mechanism in which a hydraulic and pneumatic actuator for generating the adjusting thrust is housed in a shaft case may be employed. it can.

(2) The shaft case may be provided as an independent oil chamber in the crankcase, and the oil level may be raised to a position near the axis of the rotating shaft to achieve the spray lubrication.

[0033]

As described above, according to the present invention, (1) a drive shaft 42 provided with a drive sheave 45 and a drive sheave thrust generating mechanism 44, and a cylindrical driven shaft provided with a driven sheave 57. 55 and a V-belt type automatic transmission including a V-belt 46 wound between the two wheels 45 and 57, the drive wheel 45 on the drive shaft 42 and the drive wheel thrust generating mechanism 44 The rear surface of the movable sheave 81 of the drive sheave 45 is not covered with the drive sheave thrust generating mechanism, the cover, etc. Since the driving gear 45 is efficiently cooled, the heat radiation of the V-belt 46 is improved, and the life of the belt is prolonged.

(2) Since the drive wheel thrust generating mechanism 44 is housed in the shaft case 27 and is lubricated with oil, it is not necessary to cover the movable sheave 81 with a rubber cover or the like for holding lubricating oil as in the prior art. It is possible to further increase the rotation speed or the transmission power, and to improve the durability and maintainability of the drive adjusting thrust generating mechanism.

(3) As in the second aspect of the present invention, the drive sheave thrust generating mechanism 44 is housed in the shaft case 27 supporting the drive shaft 42, and the drive sheave 45 is provided outside the shaft case 27. Since it is arranged, the surface of the drive pulley 45 is exposed to the outside, and the heat release effect is enhanced.

(4) As in the third aspect of the present invention, the drive wheel thrust generating mechanism 44 is hermetically sealed in the shaft case 27, and the drive wheel thrust generating mechanism 44 is oil-lubricated in the shaft case 27. Accordingly, unlike the conventional lubricating structure in which the grease or the like is confined in the rubber cover, the drive adjusting thrust generating mechanism can be effectively cooled.

[Brief description of the drawings]

FIG. 1 is a left side view of a scooter type motorcycle to which the present invention is applied.

FIG. 2 is a plan view of FIG.

FIG. 3 is an enlarged partial sectional view taken along the line III-III of FIG. 1;

FIG. 4 is an enlarged partial view taken along the line IV-IV of FIG. 1;

FIG. 5 is a longitudinal sectional view of a conventional example.

[Explanation of symbols]

27 Shaft Case 42 Rotating Shaft (Drive Shaft) 44 Drive Shaft Thrust Generating Mechanism 45 Drive Shaft 47 V-belt Type Automatic Transmission 55 Cylindrical Driven Shaft 57 Driven Shaft 80 Fixed Sheave of Drive Shaft 81 Movable sheave 84, 85, 86 Lubrication passage, lubrication oil chamber, lubrication passage (oil lubrication mechanism)

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[Procedure amendment]

[Submission date] January 29, 1997

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Figure 3

[Correction method] Change

[Correction contents]

FIG. 3

Claims (3)

[Claims] 1. A V-belt type automatic drive system comprising a drive shaft provided with a drive sheave and a drive sheave thrust generating mechanism, a driven shaft provided with a driven sheave, and a V-belt wound between the two wheel sheds. A V-belt type automatic transmission, wherein a drive sheave on a drive shaft and a drive sheave thrust generating mechanism are axially separated from each other. 2. A V-belt type automatic transmission according to claim 1, wherein a drive sheave thrust generating mechanism is housed in a shaft case supporting the drive shaft, and the drive sheave is arranged outside the shaft case. A V-belt type automatic transmission characterized by: 3. The V-belt type automatic transmission according to claim 2, wherein a drive adjusting thrust generating mechanism is sealed in the shaft case,
A V-belt type automatic transmission characterized in that a drive gear driving thrust generating mechanism is oil-lubricated in a shaft case.