JPS63246552A - Belt-type automatic transmission - Google Patents

Abstract

PURPOSE:To reliably accomplish interruption of power by loosely fitting an eccentric bush to the outer periphery of a driving shaft between fixed and movable faces, whereby a ventral base of a V-belt is supported during idling or stopping and separated from both faces by an outer peripheral cam surface of the bush. CONSTITUTION:During idling or stopping of an engine, a ventral base 3b of a V-belt 3 is supported by an outer peripheral cam surface 16 of an eccentric bush 15 loosely fitted to the outer periphery of a driving shaft 1 between fixed and movable faces 4, 5 of a drive side V-pulley 2 through a face boss 8. When rotating power more than designated is applied to the driving shaft 1 or a car is moved during stopping of an engine, the V-belt 3 and the eccentric bush 15 start rotating in a body, so that a large-diameter side cam surface 16b pushes up the V-belt 3 to the outside of a V-shaped annular groove 6, and both side surfaces 3a of the V-belt 3 are separated from both faces 4a, 5a to interrupt the power transmission between the V-pulley 2 and the V-belt 3. Thus, interruption of power can be reliably accomplished, and the whole of the apparatus can be reduced in size.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is directed to a V-belt that is wound around a loop of a drive shaft such as a crankshaft, which is rotated by the rotational force of the drive shaft. The winding of the V-shaped annular groove of the V-pulley is a belt-type automatic transmission device that automatically changes the power of the drive shaft by changing the diameter, and is especially suitable for belt-type automatic transmission devices that are equipped with a crutch mechanism that intermittents the power of the drive shaft. -Relating to automatic transmissions.

[Conventional technology]

In conventional belt-type automatic transmissions used in motorcycles such as scooters, the drive V pulley on the crankshaft and the driven pulley on the driven shaft are directly connected by a V belt, so for example when the engine is idling. Due to the tension of the V-belt, the power from the crankshaft may be transmitted to the rear wheel, or the crankshaft may rotate when the rear wheel is rotated. As disclosed in the official gazette, there is a device that is provided with a clutch mechanism to prevent this problem.

This clap mechanism has a rotating shaft that is a driving shaft or a driven shaft, a fixed face that rotates in parallel with the rotating shaft, and a movable face that moves in the axial direction on a support shaft, and the right-handed winding If of the belt. ) A pulley whose diameter can be changed is formed, and an idling body is provided at an appropriate location inside each face to rotate freely relative to each face when the belt is engaged, thereby disconnecting the boot from the belt. As a more preferred embodiment, a bearing is interposed between the idling body and the face to ensure smooth connection and disconnection.

[Problem that the invention seeks to solve]

However, in the above-mentioned system, the heavy idling element is attached to the tip of the high-speed driving e-shaft, which is undesirable from the viewpoint of engine crank durability. Since the idle rolling element rotates together with the belt, the resistance force is large.

Furthermore, in devices that use bearings, the bearings themselves are expensive, and it is necessary to supply grease to the bearings and seal them, resulting in an unavoidable increase in costs.

The present invention was made against the background of the above circumstances, and an object of the present invention is to provide a belt-type automatic transmission that is inexpensive, has excellent durability, is small and lightweight, and has a latch mechanism.

[Means for solving the problem]

In order to achieve the above object, the present invention consists of a fixed face that rotates together with the drive shaft and a movable V face that moves and covers the drive shaft in the axial direction. In a belt-type automatic transmission device in which the diameter of the V-shaped annular groove between both faces can be changed by the rotational force of The bushing supports the bottom surface of the V-belt that moves toward the inner diameter side of the V-shaped annular groove when the engine is idling or stopped, and
It is characterized by having a cam surface on the outer periphery that moves the belt toward the outer diameter side of the V-shaped annular groove and separates the V-belt from both of the faces.

[For production]

According to the above configuration, when the engine is idling or stopped, the V-belt has its bottom surface supported by the cam surface on the outer periphery of the eccentric bushing.

In addition, if a rotational power exceeding a certain level is applied to the drive shaft, or if the vehicle is moved with the engine stopped, the V-belt and eccentric bushing will begin to rotate together, and the large-diameter cam surface of the eccentric bushing will rotate around the V-belt. Push up toward the outer diameter side of the V-shaped annular groove, and
Both side surfaces of the belt are separated from the face surfaces of both faces, and power transmission between the pulleys and the V-belt is interrupted.

〔Example〕

An embodiment in which the present invention is applied to a crankshaft of a motorcycle will be described below with reference to the drawings.

At one end of the crankshaft 1, which is the drive shaft, there is a V for the drive CJ.
Is Pulley 2 equipped? 3. The V-pulley 2, the rear wheel pulley RP shown in FIG. 5, and both pulleys 2. R.I.
) and the V-belt 3 wound between them constitutes a belt-two self-transmission device, and the power of the crankshaft 1 is transmitted from the pulley 2 to the V-pulley RP via the V-belt 3, which drives the rear wheels. .

The driving V-pulley 2 consists of a fixed face 4 that rotates together with the crankshaft 1 and a movable face 5 that moves in the axial direction on the crankshaft 1. , a V-shaped annular groove 6 is formed that supports both side surfaces 3a, 3a of the V-belt 3 with tapered face surfaces 4a, 5a.

The fixed face 4 is attached to the shaft end of the crankshaft 1.
7, and the movable face 5 is fixed at the crank 11.
It is fitted on the face boss 8 fitted on the crankshaft 1b1 so as to be movable in the axial direction of the crankshaft 1.

n'J fJJ face 5 moves in the axial direction, ■
By expanding and contracting the letter-shaped annular vortex 6 and changing the winding diameter supporting the V-belt 3 to the outer diameter or inner diameter side, the rear wheel side V
The winding diameter of the V-belt 3 wound around the pulley RP 11H is changed to the inner diameter or the outer diameter side to automatically change the speed of the rotation of the crankshaft 1. The lamp plate 11 that rotates together with the crankshaft 1 is disposed, and the way I and the fixed face 4 are pushed between the bent portions 11a of the lamp plates 1 and 11 and the mounting portions 5b of the movable face 5. A roller 12 is interposed.

A movable face spring 13 is compressed between the lamp plate 11 and the seal cover 10, and the mounting recess 5b of the movable face 5 is normally pressed toward the lamp plate 11 by the biasing force of the movable face spring 13. but,
The weight roller 12 is held on the inner peripheral side.

A concave groove 14 is provided around the face boss 8 between both faces 4.5 at the end on the fixed face 4 side.
m has been done.

The eccentric bushing 15 is formed of an oil-impregnated bushing having excellent self-lubricating properties, and has a small diameter surface 16a on the outer periphery with the axis 01 of the crankshaft 1 as a fulcrum, and a distance of 8 minutes from the center of the small diameter surface 16a. An oval cam 16 with a large diameter portion 16b whose fulcrum is the shaft center 02, and a V-bell 1~ which moves the ■-shaped annular FS6 to the inner diameter side when the engine is idling or stopped. 3 has its ventral bottom surface 3b supported by this cam 16, and due to the loose fitting of the eccentric bushing 15, one side 3a of the bells 1 to 3 is spaced apart from the face surface 4a of the fixed face 4. , a neutral gap C is provided between the two.

Next, the operation of this embodiment configured as described above will be explained.

In the state shown by the solid line in Fig. 1, where the crankshaft 1 rotates at a low speed due to idling, etc., the fixed face 4 of the pulley 2 and the ramp plate 11 rotate together with the crankshaft 1, and furthermore, the rotation of the ramp plates 1 and 11 is (transmitted to the movable face 5 via the weight roller 12), but since the belt 3 is wound with moderate tension between the V-pulley RP on the rear wheel side, the It does not rotate due to slipping on the surface 3a.

Then, as the rotation of the crank @1 gradually increases, the centrifugal load on the weight roller 12 increases, and the weight roller 12 moves toward the outer circumference against the +-1 force of the movable face spring 13.
As a result, the movable face 5 moves toward the fixed face 4 while narrowing the interval between the V-shaped annular grooves 6, and the V-belt 3, which was located on the small diameter side of the annular groove 6, changes its winding number diameter. while being pushed up toward the larger diameter side of the V-shaped annular groove 6,
When the crankshaft 1 rotates at high speed, the movable face 5 and V
The belt 3 is in the position indicated by the imaginary line in FIG.

Further, when the rotation of the crankshaft 1 during high-speed rotation decreases, the weight roller 12 located on the outer circumferential side is gradually returned to the inner circumferential side, and the movable face 5 is accordingly moved by the biasing force of the movable face spring 13. ■ Bell, which was located on the large diameter side, moved toward the lamp plate 11 while widening the interval between the V-shaped annular grooves 6!・3, the winding moves to the small diameter side of the V-shaped annular groove 6 without changing the diameter, and when the engine is idling or stopped, The V-belt 3 returns to the position shown by the solid line in FIG. It becomes neutral and stops rotating.

Here, for example, if the V-belt 3 in the neutral state is misaligned, or if the crankshaft 1 rotates at more than the set idling speed, the positional relationship between the V-belt 3 and the V-pulley 2 may become misaligned. , the side surfaces 3a, 3a contact the face surfaces 4a, 5a of both faces 4.5, and the face boss 8
It begins to rotate with the eccentric bushy 115 loosely fitted into the
When the large-diameter surface 16b of the cam surface 16 of the eccentric bushing 15 rotates toward the side where the V-belt 3 is wound (upper side in FIGS. 3 and 4), the large-diameter surface 16b guides the belt 3 into the V-shaped annular groove. 6 in the direction of the larger diameter, and the side surface 3a.

3a is separated from the face surfaces 4a, 5a of both faces 4.5, the V-belt 3 is not rotated.

In addition, when a motorcycle with the engine stopped is pushed and moved, the rotation of the rear wheel is transmitted from the rear wheel side ■ pulley RP to the V belt 3, but the drive side V pulley starts rotating together with the V belt 3. The eccentric bushing 15 of No. 2 connects the V-bell l-3 with the large diameter surface 16b of the cam surface 16 to both face surfaces 4a,
5a, the rotation of the rear wheel is not transmitted to the crankshaft 1.

The bell l-3 is separated from both face surfaces 4a and 5a by the eccentric bush 15, and the movable face 5, which moves toward the fixed face 4 as the crankshaft 1 rotates, narrows the interval between the V-shaped rings 1116. Go, both face surfaces 4a,
5a again supports the side surface 38.3a and pushes it up toward the larger diameter side, thereby driving the V-belt 3, and the bottom surface 3b of the belt 3 is separated from the cam surface 16 of the eccentric bushing 15.

As described above, the eccentric bushing of this embodiment, which serves as the clutch mechanism of a belt type automatic transmission, is formed as a small and lightweight single unit, so it is possible to reliably achieve 1g1Fi of crank power without increasing the size of the entire device. , simple, durable, and inexpensive to manufacture.

The shape of the cam on the outer periphery and the mounting position of the cam bushing of the present invention are not limited to those of the above-mentioned embodiments, but can be changed as appropriate according to the shape of the pulley.

[Efficacy of invention Song Dynasty]

As explained above, an eccentric bushing is loosely fitted to the outer periphery of the drive shaft of the fixed and movable face pulley of the drive V-pulley, and the V-shaped annular groove is formed on the outer periphery of the eccentric bushing when the engine is idling or stopped. At the same time, the V-belt is moved to the outer diameter side of the V-shaped annular groove, and the V-belt is moved from both faces to the I
l! Since we have provided a cam surface that allows the drive shaft to move in, even if rotational power exceeding a specified level is applied to the drive shaft or the vehicle is moved with the engine stopped, the eccentric bushing will prevent the power from being disconnected from the drive pulley and bell l-fJ. You can definitely do it.

In addition, the eccentric bushing is a simple single item, lightweight and small, so it is durable and can be manufactured at low cost.
There are various advantages in that the entire device can be made smaller.

[Brief explanation of the drawing]

The figure is part of the invention 7I! ! As an example, Figure 1 shows V
A cross-sectional front view of the V-boot in which the belt is supported by the small diameter surface of the cam surface of the eccentric bushing.
The figure is a cross-sectional front view of a V-pulley in which the V-belt is supported by the large-diameter cam surface of the eccentric bushing, and Figure 4 is IV-IV of Figure 3.
FIG. 5 is a cross-sectional plan view of the belt-type automatic transmission device. 1... Crankshaft 2... V-pulley on the drive side 3.
...V belt 3a...Side surface 3b...Body bottom surface 4...Fixed face 5...Movable face 4a, 5a...Face surface 5b...Mounting recess 6...V-shaped annular groove 8...Face boss 1
1...Ramp plate ° 12...Weight row 513...Movable face spring 14...Concave groove 15...Eccentric bushing 16...Cam surface 16
a...Small diameter surface of cam surface 16 16b...Cam surface 1
Large diameter surface of 6 RP... Driven side pulley C...
Gap for neutral 0+, 02...Axis center
S... Distance between axis 01.02 Procedural amendment 1-Pa April 21, 1986

Claims (1)

[Claims] 1. A V-belt is wrapped around a drive V pulley, which consists of a fixed face that rotates together with the drive shaft and a movable face that moves in the axial direction on the drive shaft. In a belt-type automatic transmission device in which the winding diameter of the annular groove can be changed, an eccentric bushing is loosely fitted around the outer periphery of the drive shaft between the two faces, and the eccentric bushing is configured to adjust the diameter of the groove when the engine is idling or stopped. A cam surface that supports the bottom surface of the V-belt that moves toward the inner diameter side of the V-shaped annular groove and moves the V-belt toward the outer diameter side of the V-shaped annular groove to separate the V-belt from both faces is attached to the outer periphery. A belt type automatic transmission device characterized by having the following features: