JPH11141632A - Accessory driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure and reduce a manufacturing cost and an arrangement space. SOLUTION: A variable diameter pulley A which has a power transmission ring 6 held between a pair of pulley main bodies 2, 3 in a freely deviating manner to be wound on an endless belt 7 is provided on the shaft of an accessory. In the variable diameter pulley A, an elastic member and an inertial member are built to energize the power transmission ring 6 to the concentrical side via the pulley main bodies 2, 3. Energizing force to the concentric side, which the inertial member gives to the power transmission ring 6 is increased/ decreased according to the rotating speed of the variable diameter pulley A. At a position where force of deviating the power transmission ring 6 with the tension of a tensioner 55 by the elastic member 57 is balanced with force of energizing the power transmission ring 6 to the concentric side with the elastic member and the inertial member of the variable diameter pulley A, the power transmission ring 6 is automatically displaced to achieve automatic speed change.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accessory driving device for driving an accessory by a drive source.

[0002]

2. Description of the Related Art Conventionally, as a device for driving an auxiliary machine by an automobile engine, a drive pulley provided on an output shaft connected to a crankshaft of the engine and a driven pulley provided on an input shaft of the auxiliary machine have been used. There is a belt transmission in which an endless belt is wound. However, when the engine rotates at a high speed, the input shaft of the accessory is rotated at an unnecessary high speed, which is not preferable in terms of energy saving, and also has a problem that the durability of the accessory is affected.

Therefore, there has been provided a belt transmission device using a variable diameter pulley capable of changing the effective diameter of the belt as a driving pulley or a driven pulley. In this belt transmission device, a tensioner for speed ratio adjustment driven by a driving means such as a hydraulic actuator or an electric motor pulls the belt while increasing the belt tension, thereby increasing the effective diameter of the variable diameter pulley. Change the gears.

[0004]

However, this belt transmission uses a mechanism such as a tensioner for adjusting the speed ratio, a drive mechanism for driving the tensioner, and a controller for controlling the operation of the drive mechanism. Therefore, there are problems that the number of parts is large, the structure is complicated, the manufacturing cost is high, and the arrangement space is wide.

[0005] The present invention has been made in view of the above problems, and can simplify the structure, reduce the manufacturing cost,
It is another object of the present invention to provide an accessory driving device capable of reducing an arrangement space.

[0006]

Means for Solving the Problems As means for solving the above problems, the invention according to claim 1 is a power transmission ring around which an endless belt is wound, and the power transmission ring can be eccentric. A pair of pulley bodies that are sandwiched between and can transmit power to the rotating shaft of the auxiliary machine, an elastic member that urges the power transmission ring to a concentric position through the pulley body, A variable diameter pulley including an inertia member for pressing the power transmission ring to a concentric position by pushing the power transmission ring, and an elastic member for applying tension to the belt via a tensioner pulley so as to bias the power transmission ring to the eccentric side. A tensioner, an elastic member of the tensioner tries to decenter the power transmission ring via a belt, and an elastic member and an inertia member of the variable-diameter pulley have a power transmission ring. By balance and the force for urging the grayed to concentric position, is characterized in that the position of the power transmission ring is defined.

In this configuration, the belt tension by the elastic member of the tensioner tries to displace the power transmission ring to the eccentric side, and the elastic member and the inertia member displace the power transmission ring to the concentric side via both pulleys. If an imbalance occurs with the force to be caused, the power transmission ring is displaced to a position where both forces are balanced in an attempt to eliminate the imbalance. In other words, when the centrifugal force of the inertia member increases with an increase in the rotational speed of both pulleys, the force by which the elastic member and the inertia member try to displace the power transmission ring concentrically becomes relatively large. Means that the power transmission ring is displaced concentrically. Conversely, the centrifugal force of the inertia member decreases as the rotational speed of both pulleys decreases, and the force by which the elastic member and the inertia member try to displace the power transmission ring concentrically is the belt tension. Becomes smaller than the force for displacing the power transmission ring toward the eccentric side, the power transmission ring becomes eccentric.

When the tensioner pulley of the tensioner approaches the belt, the amount of bending of the elastic member of the tensioner decreases, and the belt tension exerted by the elastic member of the tensioner decreases. On the other hand, when the belt is slackened and the power transmission ring of the variable diameter pulley is displaced in an eccentric direction, the belt tension exerted by the elastic member built in the variable diameter pulley via the pulley main body and the power transmission ring increases. Therefore, the position of the power transmission ring is determined by taking into account the characteristic that the elastic members of the tensioner and the variable diameter pulley depend on the position and the characteristic that the inertia member depends on the rotational speed, and determine the effective diameter of the variable diameter pulley. The shift is achieved through the change of

According to a second aspect of the present invention, in the first aspect, the variable-diameter pulley is connected to one of the pulley main bodies so as to be integrally movable in the axial direction, and the other of the pulley main body has a power transmission surface. It further includes a facing member including a facing surface facing the back surface, wherein the inertial member is housed in a housing space defined between the facing surface of the facing member and the back surface of the other pulley main body. It is assumed that.

In this configuration, the inertia member is displaced in the accommodation space in the centrifugal direction, thereby bringing the two pulley main bodies closer to each other and displacing the power transmission ring concentrically. Here, the accommodating space for accommodating the inertial member needs to have a wedge-like shape in which the width in the axial direction becomes narrower outward in the radial direction. For that purpose, at least one of the back surface of the second pulley main body and the facing surface of the facing member may be formed in a tapered shape.

According to a third aspect of the present invention, in the second aspect, the inertial member includes a rolling member that rolls on an opposing surface of the opposing member and a back surface of the main body of the second pulley. Is what you do. With this configuration, the inertial member can be smoothly displaced by rolling the rolling member. It is possible to prevent a situation in which the inertial member is pinched between the opposing surface of the opposing member and the rear surface of the second pulley main body and does not move.

As the above-mentioned rolling member, a ball, a roller and the like can be exemplified. In the case of rollers, it is preferable to provide a groove to guide the movement in the centrifugal and centripetal directions,
When the surface on which the rollers roll is a tapered surface, it is preferable to perform crowning on the outer peripheral surface of the rollers. In addition, a shaft member that penetrates the rollers may be provided, and the rollers may be rotatably supported by the shaft members via a bearing such as a metal bush. In this case, the opposing surface of the opposing member and the second
The roller may be guided by one of the back surfaces of the pulley main body, and the shaft member may be guided by the other.

[0013] The invention according to claim 4 is based on claim 1,
(2) or (3), the variable diameter pulley includes first connecting means for connecting both pulley main bodies so as to be integrally rotatable;
And a second connecting means for connecting both pulley main bodies to the rotating shaft so as to transmit power via the connecting means. In this configuration, the second connecting means includes:
Since the two pulley bodies are collectively connected to the rotary shaft via the first connecting means for connecting the both pulley main bodies so as to be integrally rotatable, compared with a case where each pulley main body is individually connected to the rotary shaft, The structure can be simplified.

According to a fifth aspect of the present invention, in the fourth aspect, the first connecting means includes a diaphragm spring in which an inner diameter portion and an outer diameter portion are respectively rotatably engaged with corresponding pulley main bodies. The diaphragm spring is characterized in that it also serves as the elastic member. In this configuration, since the diaphragm spring that connects the two pulleys so as to be integrally rotatable also serves as the elastic member, the structure can be simplified. Further, since the diaphragm spring can directly urge both pulley main bodies, the both pulley main bodies can be smoothly displaced, so that a smooth shift can be achieved.

The diaphragm spring includes a plurality of connecting holes arranged at a radially intermediate portion at circumferentially spaced intervals, and the second connecting means controls only the circumferential displacement of the diaphragm spring. It is preferable to include a connection shaft engaged with the inner surface of the connection hole. In this case, by setting the radial position of the connection hole of the diaphragm spring to a predetermined value, the inner diameter portion and the outer diameter portion of the diaphragm spring are rotated in opposite directions (with respect to the axial position of the connection hole) with the same displacement amount. The direction can be displaced. As a result, the two pulley main bodies can be displaced in the axial direction in opposite directions by the same displacement amount, so that the center of the belt can be kept constant regardless of the speed change.

According to a sixth aspect of the present invention, in the fourth aspect, the second connecting means converts the rotational angular displacement of each pulley main body with respect to the rotational axis into a pair of axial displacements opposite to each other. It is characterized by including a conversion mechanism. In this configuration, for example, when a fluctuating load torque is applied, the load torque is converted into a force that brings both pulley main bodies closer to each other by the pair of conversion mechanisms. The force can be increased. Thereby, it is possible to prevent the occurrence of slippage between the power transmission ring and the power transmission surface mainly composed of both pulleys.

Here, the pair of conversion mechanisms are exemplified by a pair of cam mechanisms having a cam surface and a cam follower engaged with the cam surface, wherein the cam surfaces of the respective cam mechanisms are inclined in opposite directions. can do. In addition, in a pair of screw coupling mechanisms, one in which the screws of each screw coupling mechanism are mutually reverse screws can be exemplified. In addition,
It is preferable that the pair of conversion mechanisms displace the two pulley main bodies in the opposite directions and with the same amount of displacement. In this case, the belt center can be maintained constant regardless of the shift.

[0018]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view of a variable-diameter pulley A included in an accessory driving device according to an embodiment of the present invention. FIGS. 2A and 2B are schematic structural views showing a main part of an accessory driving device B using the variable diameter pulley A.

The variable-diameter pulley A is shown in FIG.
A power transmission ring 6 that can be displaced from an eccentric state as shown in FIG. 2A to a concentric state as shown in FIG.
And the effective diameter of the belt 7 wound around the power transmission ring 6 can be changed. The power transmission ring 6 is sandwiched between the first and second pulley bodies 2 and 3.

In the accessory driving device B, the endless belt 7 is driven by a variable-diameter pulley A via a displaceable tensioner pulley 56 of a tensioner 55 and a fixed idler pulley 58.
Is wound around the power transmission ring 6. Tensioner 5
5 is provided with an elastic member 57 that urges the tensioner pulley 56 in a direction to approach the belt 7, and this elastic member 57 tends to decenter the power transmission ring 6 via the belt 7.

2 (a) and 2 (b), the structure of the tensioner 55 is schematically shown.
Various known structures can be used.
That is, as the tensioner 55, a fixed member, a movable member provided to be displaceable on the fixed member, a tensioner pulley rotatably supported by the movable member and engaged with the belt, and a movable member An elastic member that urges the tensioner pulley in a direction to pull the belt can be used. As the movable member, it is possible to use a swinging member having a base end portion supported by the fixed member so as to be swingable around a predetermined rotation axis and a tip end portion rotatably supporting the tensioner pulley. . Further, a linear moving member supported by a fixed member so as to be linearly displaceable can be used as the movable member.

On the other hand, the variable diameter pulley A is provided with an urging member for urging the power transmission ring 6 to the concentric position side via the pulley main bodies 2 and 3 as described later in detail. The biasing member is an elastic member (corresponding to the diaphragm spring 11 in FIG. 1) that generates a loose-side tension G on the belt 7 via the power transmission ring 6 in accordance with the relative displacement of the pulley bodies 2 and 3 in the axial direction. ), And an inertia member (corresponding to the inertia member 47 in FIG. 1) that generates the loose side tension H on the belt 7 via the power transmission ring 6 according to the rotation speed of the variable diameter pulley A.

A position where the resultant force (G + H) of the tensions G and H generated by the elastic member and the inertia member of the variable diameter pulley A and the tension F of the belt 7 generated by the elastic member 57 of the tensioner 55 are balanced. Then, the power transmission ring 6 and the elastic member 57 of the tensioner 55 are displaced. The inertia member is displaced in the centrifugal direction according to the rotation speed, and biases the power transmission ring 6 to the concentric position side via the pulley main bodies 2 and 3, and the centrifugal member that adjusts the gear ratio according to the rotation speed. It functions as an automatic speed ratio adjustment mechanism.

That is, when the running speed of the belt 7 is relatively low, the tension H due to the inertial member is small. Therefore, as shown in FIG. 2A, when the elastic member 57 of the tensioner 55 is displaced toward the contraction side and the power transmission ring 6 is displaced toward the eccentric side, the tension F and the tension G + H are balanced. become. Therefore, the effective diameter of the belt 7 becomes smaller with respect to the variable diameter pulley A, and the rotation speed of the rotating shaft provided with the variable diameter pulley A becomes relatively faster than the rotation speed of the driving pulley.

Conversely, when the running speed of the belt 7 is high, the tension H due to the inertia member is large. Therefore, FIG.
As shown in (b), in a state where the elastic member 57 of the tensioner 55 is displaced to the extension side and the power transmission ring 6 is displaced to the concentric side, the tension F and the tension (G + H) are balanced. Therefore, the effective diameter of the belt 7 is large with respect to the variable diameter pulley A, and the rotation speed of the rotating shaft provided with the variable diameter pulley A is relatively slower than the rotation speed of the driving pulley.

FIG. 3 is a graph showing the relationship between the rotation speed of the driving pulley and the rotation speed of the variable-diameter pulley. In FIG. 3, power is transmitted in the region where the rotation speed of the driving pulley reaches the rotation speed V1. The ring 6 is eccentric with the maximum amount of eccentricity, and the rotation speed of the variable diameter pulley A increases at a constant increase rate. In the range from the rotation speed V1 to the rotation speed V2, the eccentricity of the power transmission ring 6 is gradually reduced and the effective diameter of the variable diameter pulley A is increased. The rate of increase decreases. When the rotation speed V3 is reached, the power transmission ring 6 becomes concentric, and the variable diameter pulley A has the maximum effective diameter. In the region where the rotation speed is V3 or higher, the rotation speed of the variable diameter pulley A is increased at a slightly smaller rate than the region. Increase.

Referring to FIGS. 1 and 4, the variable diameter pulley A includes a rotating shaft 1 which is rotatably connected to a rotating shaft of, for example, an auxiliary device of an automobile. The two pulley bodies 2 and 3 are movable in the axial direction of the rotary shaft 1 and have an annular shape. These pulley main bodies 2 and 3
Are formed with conical tapered power transmission surfaces 4 and 5, respectively. These pair of power transmission surfaces 4,
5 are tapered so as to be inclined in opposite directions to each other.
Are held eccentrically with respect to the axis K of the pulley main bodies 2 and 3. The power transmission ring 6 has a substantially trapezoidal cross section. FIG. 1 shows a state where the power transmission ring 6 is eccentric with the maximum amount of eccentricity, and FIG. 4 shows a state where the power transmission ring 6 is at the concentric position. The effective diameter D of the belt 7 is changed according to the displacement of the power transmission ring 6. L is a position of the width center of the belt 7 (hereinafter, referred to as a belt center L).

A power transmission surface 8 to the belt 7 is formed on the outer peripheral surface of the power transmission ring 6, and the belt 7 is wound around the power transmission surface 8. The transmission surface 8 has a rib 7a of the belt 7
A peripheral groove 8a is formed which meshes with. Both side surfaces of the power transmission ring 6 constitute power transmission surfaces 9 and 10 that contact the corresponding power transmission surfaces 4 and 5 to transmit torque.

The belt 7 is preferably made of rubber, and the power transmission ring 6 is made of a resin having an excellent durability and a high friction coefficient, for example, a phenol resin mixed with carbon fiber, aromatic polyamide fiber and graphite. It is preferable to use a molded resin material. With this resin, despite its high strength and excellent wear resistance,
The aggressiveness to the mating member is gentle, and the friction coefficient is stable regardless of the temperature. The content ratio of carbon fiber, aromatic polyamide fiber and graphite in the resin material is 5 to 30% by weight of carbon fiber, 5 to 15% by weight of aromatic polyamide fiber, and 10 to 10% by weight of graphite.
Being in the range of 15% by weight improves abrasion resistance,
This is preferable in that the coefficient of friction is made more stable.

The variable-diameter pulley serves as an urging means for urging the first and second pulley main bodies 2 and 3 in a direction approaching each other, and connects the two pulley main bodies 2 and 3 so as to be integrally rotatable. 1 is provided with a diaphragm spring 11 as a connecting means.
Is connected via a plurality of connection shafts 13 to a connection portion 12 formed of a conical annular plate that rotates in conjunction with the rotation shaft 1 so as to be integrally rotatable. A second connecting means is constituted by the connecting portion 12 and the plurality of connecting shafts 13. An inner peripheral portion of the connecting portion 12 is connected to an outer peripheral portion of a flange portion la formed integrally with the rotating shaft 1 so as to be integrally rotatable by a spline connection. Movement has been stopped.

The inner diameter portion 14 and the outer diameter portion 15 of the diaphragm spring 11 are respectively engaged with the first and second pulley bodies 3 so as to be integrally rotatable. Thereby, both pulley main bodies 2 and 3 and diaphragm spring 1
1 is configured to rotate integrally with the rotating shaft 1. For example, when this variable diameter pulley is applied to a driven pulley as in the present embodiment, the power transmission ring 6,
Torque is transmitted to the rotating shaft of the accessory via the two pulley main bodies 2 and 3, the diaphragm spring 11 and the rotating shaft 1.

Referring to FIG. 1 and FIG. 5, radial connection grooves 16 and 17 are provided on the inner diameter portion 14 and the outer diameter portion 15 of the diaphragm spring 11, respectively.
Are formed. In addition, the diaphragm spring 11
In the radially intermediate portion, connecting holes 31 that penetrate the above-described connecting shaft 13 and connect the diaphragm spring 11 and the connecting portion 12 so as to be able to transmit torque are formed in a circle at equal intervals.

Referring to FIG. 1, first pulley main body 2 includes
A disk portion 18 having the power transmission surface 4 formed thereon, and a shaft portion 19 fixed to the inner periphery of the disk portion 18 so as to be integrally rotatable and arranged concentrically with the rotating shaft 1 are provided. This shaft 19
A tapered portion 20 is formed at one end of the tapered portion.
The disk portion 18 is fitted into the base plate and fixed by a nut 21.

The other end of the shaft portion 19 has a cylindrical boss portion 2 concentric with the rotating shaft 1 and having a larger diameter than the shaft portion 19.
2 are integrally formed. The boss portion 22 is slidably supported in the axial direction on the peripheral surface of the rotating shaft 1 via a bush 23 as a sliding bearing. The second pulley main body 3 includes a conical disk portion 24 forming the power transmission surface 5.
And a cylindrical boss portion 25 formed on the inner periphery of the disk portion 24. Boss portion 25 of second pulley main body 3
Surrounds a portion of the shaft portion 19 of the first pulley main body 2 and a part of the boss portion 22, and the shaft portion 19 of the first pulley main body 2
And bosses 22 are slidably supported in the axial direction via bushes 26 and 27 as sliding bearings, respectively.

The back surface 28 of the power transmission surface 5 of the second pulley main body 3 is formed as a conical tapered surface having a generatrix parallel to the power transmission surface 5. The outer peripheral edge of the second pulley main body 3 has a section L
A ring-shaped annular flange portion 32 is integrally extended, and a plurality of connecting grooves 17 of the outer diameter portion 15 of the diaphragm spring 11 are fitted into a surface of the annular flange portion 32 on the side of the diaphragm spring 11. A plurality of plate-like connecting projections 29 are formed radially at equal intervals on the circumference. The annular flange portion 32 of the second pulley main body 3 is pressed by the outer diameter portion 15 of the diaphragm spring 11 so that the second pulley main body 3 approaches the first pulley main body 2 (to the left in FIG. 1). Being energized.

The shaft portion 19 and the boss portion 22 of the first pulley main body 2 extend through the boss portion 25 of the second pulley main body 3 toward the back surface 28 of the power transmission surface 5 of the second pulley main body 3. The boss portion 22 constitutes a portion extending to the back side of the second pulley main body 3. At the end of the boss portion 22 as a portion extending to the rear side, a connecting portion 30 formed of an annular flange for integrally rotating the end portion and the inner diameter portion 14 of the diaphragm spring 11 is integrally formed. ing.

The inner peripheral portion of the connecting portion 30 is screwed to the end of the boss portion 22 and is fixed so as to be integrally rotatable. The torque transmitted via the connecting portion 30 acts in the screw tightening direction, so that the fixing is not loosened. The connecting portion 30 has a pressing surface 33 for pressing the inner diameter portion 14 of the diaphragm spring 11 in the axial direction,
A plurality of connecting projections 34 are formed on the pressing surface 33 and are radially formed at equal circumferential intervals. The above-mentioned pressing surface 33 is pressed by the inner diameter portion 14 of the diaphragm spring 11, and the first pulley main body 2 approaches the second pulley main body 3 via the connecting portion 30, the boss portion 22, and the shaft portion 19 (FIG. 1 (to the right). The plurality of connection protrusions 34 are fitted into the plurality of connection grooves 16 of the inner diameter portion 14 of the diaphragm spring 11, respectively.

The connecting portion 12 has a plurality of through-holes 35 penetrating in the axial direction, which are formed at equal intervals around the circumference.
5, the connection shaft 13 penetrating the washer member 40 and the connection hole 31 of the diaphragm spring 11 is inserted and fixed. That is, the diaphragm spring 1
Reference numeral 1 denotes a state in which the washer member 40 and the connecting portion 12 are sandwiched between the washer member 40 and the connecting portion 12 in the peripheral portion of the connecting hole 31. In order to allow the inclination at the time of displacement, the connecting shaft 13
Are formed on the inclined surfaces 41 and 42 having a conical taper shape centered at. Each connecting shaft 13 is formed in parallel with the axial direction of the rotating shaft 1 and is fitted into a connecting hole 31 of the diaphragm spring 11 so that the diaphragm spring 11
And the connecting portion 12 are connected so that torque can be transmitted. Connecting shaft 1
As 3, for example, a rivet with a head can be used, and when a rivet is used, it can be easily fixed by caulking the tip and expanding the diameter.

Referring to FIG. 6, connecting hole 31 is formed of a long hole extending in the radial direction, and as shown in FIG. , 3
7 are formed. On the other hand, the connecting shaft 13 has a so-called two-sided cross-sectional shape, and a pair of engaging surfaces 3 respectively engaging with a pair of engaging surfaces 36 and 37 of the connecting hole 31.
8,39.

The pair of engagement surfaces 36 and 37 of the connection hole 31
Than the pair of engagement surfaces 38 and 39 of the corresponding connection shaft 13,
It is set to be longer in the radial direction of the diaphragm spring 11. Each of the engagement surfaces 36 to 39 is a surface parallel to the axial direction (the direction perpendicular to the paper surface in FIG. 6) and the radial direction (the vertical direction in FIG. 6) of the diaphragm spring 11. Both engagement surfaces 36 and 37 of the connection hole 31
The width between them is set substantially equal to the width between both engagement surfaces 38 and 39 of the connection shaft 13. Thus, the connection shaft 1
3 is engaged with the inner surface of the connection hole 31 so as to restrict only the displacement of the diaphragm spring 11 in the circumferential direction R.

The radial position of the connection hole 31 (indicated by the distance d from the axis K in FIG. 1) is determined when the axial displacement of the diaphragm spring 11 at the position of the connection hole 31 is regulated by the connection shaft 13. This is a position where the inner diameter portion 14 and the outer diameter portion 15 can be displaced in opposite directions by the same stroke amount. Referring again to FIGS. 1 and 4, an opposing member 44 having an opposing surface 43 opposing the back surface 28 of the second pulley main body 3 is integrally rotatable around the boss 22 of the first pulley main body 2. It is fixed to. The facing member 44 has a disk portion 45 and a boss portion 46, and the boss portion 46 is fitted on the outer periphery of the boss portion 22 of the first pulley main body 2.

An annular accommodation space 48 for accommodating the inertia member 47 is defined between the back surface 28 of the second pulley main body 3 and the opposing surface 43 of the opposing member 44 opposed thereto.
The outside of the housing space 48 is defined by the annular flange portion 32 having an L-shaped cross section of the second pulley main body 3, and the inside of the housing space 48 is the boss 25 of the second pulley main body 3. Is divided by Since the back surface 28 of the second pulley main body 3 is tapered, the accommodation space 48 has a wedge-shaped cross section in which the width becomes narrower outward in the radial direction.

The inertia member 47 is displaced in the accommodating space 48 in the centrifugal direction (from the state shown in FIG. 1 to the state shown in FIG. 4), and cooperates with the diaphragm spring 11 to form the two pulley main bodies 2. The power transmission ring 6 is urged to a position concentric with the axis K via the power transmission ring 3. 1 and 4
Referring to FIG. 7, inertia member 47 includes a roller 49 formed of a cylinder as a rolling member, and a spindle member 50 that penetrates through roller 49 in the axial direction. Further, the inertia member 47 includes a bearing 51 made of, for example, a metal bush that is interposed between the spindle member 50 and 49 to allow relative rotation between the roller 49 and the spindle member 50.

On the opposing surface 43 of the opposing member 44, with the green portions 53, 53 supporting both ends of the support shaft member 50,
A guide groove 52 for guiding the rolling movement of the roller 49 is formed in the radial direction. The outer circumferential surface of the roller 49 may be crowned along the axial direction. Inertia member 47
Generates a centrifugal force that increases with the rotation speed. When the inertia member 47 increases the turning diameter by this centrifugal force and moves toward the narrow side (radially outward) of the housing space 48, the two pulley main bodies 2 and 3 approach each other, and the power transmission ring 6 moves to the concentric position side. Will be displaced.

In this embodiment, the built-in inertia member 47
With a simple structure using centrifugal force, the effective diameter D of the variable diameter pulley A is automatically changed by using the balance of the force relation that displaces the power transmission ring 6 of the variable diameter pulley A, and automatically. You can change gears. Further, it is not necessary to use a conventional gear ratio adjusting tensioner, a driving mechanism for driving the tensioner, and a controller for controlling the operation of the driving mechanism. Since the use of a tensioner is sufficient, the structure can be significantly simplified, and the manufacturing cost and the space for arrangement can be significantly reduced.

Further, the inertia member 47 rolls on the back surface 28 of the second pulley main body 3 which partitions the accommodation space 48.
As a result, the inertial member 47 can be displaced smoothly, and as a result, it is possible to prevent the inertial member 47 from being stuck in the housing space 48 and not moving. Further, the connecting portion 12 as a second connecting means
However, since both pulley main bodies 2 and 3 are collectively connected to rotary shaft 1 via diaphragm spring 11 as first connecting means, each pulley main body 2 and 3 is individually connected to rotary shaft 1. In comparison, the structure can be simplified.

Further, since the diaphragm spring 11 for connecting the two pulley bodies 2 and 3 so as to be integrally rotatable also serves as an urging member, the structure can be simplified. Further, since the diaphragm spring 11 can directly bias the pulley main bodies 2 and 3, the both pulley main bodies 2 and 3 can be smoothly displaced, so that a smooth shift can be performed. Also,
Since both pulley bodies 2 and 3 connected to the inner diameter portion 14 and the outer diameter portion 15 of the diaphragm spring 11 can be symmetrically displaced in the axial direction with the same amount of displacement, smooth shifting is achieved with a simple structure. Meanwhile, the belt center L can be maintained constant.

At this time, although the diaphragm spring 11 bends, even if the axial displacement is different between the inner diameter portion 14 and the outer diameter portion 15, the connecting shaft 13 is formed in the axial direction of the connecting hole 31 of the diaphragm spring 11. To allow displacement,
Excessive stress does not occur around the connection hole 13. As a result, the durability of the diaphragm spring 11 can be improved. Further, since the center of the power transmission ring always coincides with the position of the belt center, no vibration or abnormal wear occurs on the power transmission ring.

In particular, in the present embodiment, the connecting shaft 13 has a pair of engaging surfaces 36 and 37 long along the radial direction of the connecting hole 31.
Therefore, a large contact area can be ensured, and the stress applied to the diaphragm spring 11 can be further reduced. As a result, the durability can be further improved. Further, the pulley bodies 2 and 3 follow the displacement of the belt 7 in the width direction and are displaced to a position corresponding to the actual belt center L, so that a smooth shift can be achieved with a simple structure. If the two-sided width of the connecting shaft 13 is widened to secure the above-mentioned contact area, the bending rigidity of the connecting shaft 13 is increased secondarily, thereby preventing the connecting shaft 13 from falling down when a torque is applied. As a result, it is possible to prevent the falling down from adversely affecting the diaphragm spring 11 and the connection hole 31 thereof.

In the above embodiment, the axial displacement around the connection hole 31 of the diaphragm spring 11 may be restricted by the connection shaft 13. In this case, a universal joint may be interposed between the connection shaft 13 and the connection hole 31. Next, FIG. 8 shows a variable diameter pulley included in an accessory driving device according to another embodiment of the present invention. Referring to FIG. 8, this variable diameter pulley A1 mainly differs from the variable diameter pulley of FIG. 4 in the following 1) to 3). 1) In the embodiment shown in FIG. 4, the first connecting means for connecting the two pulley bodies 2 and 3 so as to be integrally rotatable is constituted by the diaphragm spring 11.
1, the two pulley bodies 2 and 3 also serve as elastic members for urging in a direction approaching each other. In the present embodiment, however, the first connecting means is formed by an opposing member fixed to the first pulley body 62. The elastic member is formed by a compression coil spring 85 interposed between the second pulley main body 62 and the opposing member 69 while the member 69 is constituted by a plurality of connecting shafts 89 and 90 for connecting the second pulley main body 62 to the second pulley main body 62. Configured.

2) In the embodiment shown in FIG. 4, the radial position d of the connecting hole 31 of the diaphragm spring 11 is set as required so that the two pulley bodies 2 and 3 are axially displaced symmetrically to each other. In the present embodiment, the rollers 97, 97 provided at both ends of the connecting shaft 90 included in the first connecting means are connected to the first pulley main body 62.
And cam surfaces 10 formed on the opposing member 69, respectively.
Achieved by engaging 0, 101 respectively.
Each cam surface 100, 101 and the corresponding cam surface 100, 1
A pair of conversion mechanisms T, T (), which convert the rotational angular displacement of each of the pulley main bodies 62, 63 with respect to the rotary shaft 61 into axial displacements in opposite directions to each other, by rollers 97, 97 as cam followers respectively engaged with the cam shaft 01. (Also referred to as a torque cam mechanism).

3) In the present embodiment, the inertia member and the rolling member are constituted by the balls 82. More specifically, with reference to FIG. 8, the variable diameter pulley A1 includes first and second ring-shaped pulley main bodies 62 and 63 that are rotatable around a rotation shaft 61 and movable in the axial direction. With
Power transmission surfaces 64 and 65 are formed on the opposing surfaces of the pulley bodies 62 and 63, respectively. The pair of power transmission surfaces 64 and 65 are tapered so as to be inclined in opposite directions, and the power transmission ring 6 having a substantially trapezoidal cross section is formed by the two power transmission surfaces 64 and 65.
63 are eccentrically held with respect to the axis K. FIG. 8 shows a state in which the power transmission ring 6 is concentric with the axis K.

The first pulley main body 62 includes a conical disk portion 66 and a cylindrical boss portion 67 formed on the inner periphery of the disk portion 66. The disk portion 66 forms the power transmission surface 64 described above. Further, the boss portion 67 is provided with
Are slidably supported in the axial direction on bushings 68, 68 as sliding bearings. An end of the boss portion 67 is integrally connected to a later-described opposing member 69 by a screw 70. Reference numeral 71 denotes the first pulley main body 62 having the rotating shaft 6.
The stopper 71 is a stopper for preventing the shaft 1 from being pulled out. The stopper 71 is fixed to the rotating shaft 61 by a nut 72 screwed into an end of the rotating shaft 61.

The second pulley main body 63 has an annular plate portion 73 having a circular plate extending around the outer periphery of a conical plate with holes, and an inner cylindrical portion extending around the inner periphery of the annular plate portion 73. Boss part 74
And an outer cylindrical portion 75 extending around the outer periphery of the annular plate portion 73, and an intermediate cylindrical portion 76 formed at a radially intermediate portion of the annular plate portion 73. The boss 74, the outer cylinder 75, and the intermediate cylinder 76 all have a power transmission surface 65 of the second pulley main body 63.
Is formed so as to extend to the back surface 77 side of. The boss portion 74 of the second pulley main body 63 is supported on the outer peripheral surface of the boss portion 67 of the first pulley main body 62 movably in the axial direction via a bush 78 as a sliding bearing.

The opposing member 69 is formed of an annular member and has a tapered portion 7 on the back surface 77 of the second pulley main body 63.
9 has a tapered opposing surface 80. Then, the boss 74 of the second pulley main body 63 and the intermediate cylindrical portion 76
A housing space 81 is formed by the tapered portion 79 of the back surface 77 and the facing surface 80 of the facing member 69, and a plurality of balls as an inertia member and a rolling member are formed in the housing space 81. 82 are accommodated. The accommodating space 81 has a wedge-shaped cross section in which the width becomes narrower outward in the radial direction.
Is displaced in the centrifugal direction, so that both pulley main bodies 2, 3
Can be brought closer to each other.

The opposing member 69 has an inner cylindrical portion 83 radially inward of the opposing surface 80. An annular end surface portion 84 of the inner cylindrical portion 83 is 1
Is fixed to the end of the boss portion 67 of the pulley main body 2.
Thereby, the opposing member 69 rotates integrally with the first pulley main body 62 and moves integrally with the first pulley main body 62 in the axial direction.

A compression coil spring 85 is housed in the inner cylindrical portion 83 of the opposing member 69 as an elastic member for urging the pulley main bodies 62 and 63 toward each other. One end (the left end in the figure) of the compression coil spring 85 is engaged with the stepped portion 87 of the boss 74 while being fitted to the small diameter portion 86 at the tip of the boss 74 of the second pulley main body 63. The second pulley main body 63 is pressed and urged toward the first pulley main body 62 through the stepped portion 87. On the other hand, the other end (the right end in the figure) of the compression coil spring 85 is
9 is engaged with the end surface portion 84 of the inner cylindrical portion 83 of the
The first pulley main body 62 is pressed and urged toward the second pulley main body 63 through the fourth pulley 4. Also, the compression coil spring 85
The inner cylindrical portion 83 of the facing member 69 and the second pulley main body 6
Since the expansion and contraction are guided by the small diameter portion 86 of the third boss portion 74, the displacement can be performed smoothly.

The outer peripheral portion 88 of the opposing member 69 and the outer cylindrical portion 75 of the second pulley main body 63 are connected to a plurality of connecting shafts 89, 9 arranged in the radial direction as first connecting means.
0, it is integrally rotatably connected. One end of the connecting shaft 89 is fixed to the outer peripheral portion 88 of the facing member 69, and the other end rotatably supports a roller 92 via a bush 91 (see FIG. 9). This roller 92
The guide groove 93 formed in the outer cylindrical portion 75 of the second pulley main body 63 and parallel to the rotation shaft 61 and having one open end is rotatably fitted and engaged.

On the other hand, the intermediate portion of the connecting shaft 90 is
The outer cylindrical part 95 of the connecting part 94 as a second connecting means, which is formed in a two-stage cylindrical shape integrally formed around the outer periphery of the outer peripheral part, is fixed in a radial direction. 8 and 10 (a) and 10 (b), bush 9 is provided at both ends of connecting shaft 90, respectively.
6, a roller 97 is rotatably supported. Each of the rollers 97 includes a guide groove 98 formed in the outer cylindrical portion 75 of the second pulley main body 63 and an outer cylindrical portion 95 of the facing member 69.
Are rotatably fitted into and engaged with the guide grooves 99 formed in the guide grooves 99.

These guide grooves 98 and 99 are provided in FIG.
As shown in (a) and (b), they are inclined in opposite directions to each other, and cam surfaces 100 and 101 are formed by the inner surfaces of the guide grooves 98 and 99, respectively. When the two pulley bodies 62 and 63 generate a rotational angular displacement with respect to the rotation shaft 61 in accordance with the load torque on the variable diameter pulley A1, the cam surfaces 100 and 101 apply the rotational angular displacement to the two pulley bodies 62. , 63, and is converted into the axial displacement of FIG.
As shown in (b), both pulley bodies 62 and 63 are axially displaced in opposite directions and with the same amount of displacement (so-called torque cam mechanism). As a result, the position of the belt center L is maintained constant irrespective of the shift. FIG. 9A shows the power transmission ring 6.
Corresponds to the state shown in FIG.
Corresponds to a state where the power transmission ring 6 is eccentric.

In this embodiment, the same components as those in the embodiment of FIG.
The description is omitted. According to the present embodiment, similarly to the embodiment of FIG. 1, the resultant force (G + H) of the tension applied to the belt 7 by the compression coil spring 85 as the elastic member and the ball 82 as the inertial member, The power transmission ring 6 is automatically displaced to a position where the tension F applied to the belt 7 by the elastic member 57 is balanced, and has a simple structure utilizing the centrifugal force of the inertial member composed of the built-in ball 82. Thus, the automatic transmission can be achieved by automatically changing the effective diameter D of the variable diameter pulley A1.

Further, the use of the ball 82 which also serves as a rolling member as the inertia member can further simplify the structure and prevent the inertia member from being stuck in the housing space 81 and becoming immobile. It can be prevented before it happens.
Further, when the load torque is applied, the two pulley main bodies 62 and 63 are brought close to each other by the operation of the cam surfaces 100 and 101 included in the conversion mechanism (torque cam mechanism) T, and the clamping force for clamping the power transmission ring 6 is increased. The power transmission ring 6 and the power transmission surfaces 6 of both pulley main bodies 62 and 63
4, 65 can be prevented from occurring. As a result, highly efficient power transmission becomes possible.

Further, since the cam surfaces 100 and 101 are provided on the inner surfaces of the guide grooves 98 and 99 to roll the rollers 97 and 97 at both ends of the connecting shaft 90, the two pulley main bodies 62 and 63 are formed. The relative rotation with respect to the rotation shaft 61 can be smoothly converted to the axial displacement. as a result,
Shifting can be performed smoothly. Further, the pulley main bodies 62 and 63 can be displaced symmetrically in the axial direction by the function of the cam surfaces 100 and 101, so that the belt center L can be kept constant regardless of the gear shift.

The present invention is not limited to the above embodiments. For example, as the above-mentioned pair of conversion mechanisms T included in the variable-diameter pulley, a pair of screw coupling mechanisms having mutually opposite screws are used. You can also. Further, the present invention is not limited to the case where a general passive type tensioner (so-called auto tensioner) is used as the tensioner, but uses a speed ratio adjusting tensioner that actively changes the operation position of the tensioner pulley. Of course it is possible. In addition, various changes can be made within the scope of the present invention.

[0065]

According to the first aspect of the present invention, when the rotation speed of the variable diameter pulley changes, the centrifugal force of the inertia member incorporated in the variable diameter pulley changes, and the elastic member and the inertia member of the variable diameter pulley are attached to the belt. As a result, the power transmission ring is automatically displaced to a position where the resultant force of the tension exerted and the tension exerted on the belt by the elastic member of the tensioner are balanced, so that shifting is achieved. In addition, this can be achieved using a simple structure in which the inertia member is built in the variable-diameter pulley and using the above-mentioned force balance relationship. In particular, it is not necessary to use a mechanism such as a tensioner for gear ratio adjustment, a drive mechanism for driving the tensioner, and a controller for controlling the operation of the drive mechanism, and it is sufficient to use a general tensioner. The structure can be greatly simplified, and manufacturing costs and arrangement space can be reduced.

According to the second aspect of the present invention, when the inertia member is displaced in the accommodation space in the centrifugal direction, the two pulley main bodies are brought close to each other, and the power transmission ring is displaced concentrically. According to the third aspect of the present invention, the inertial member can be smoothly displaced by rolling the rolling member. It is possible to prevent a situation in which the inertial member is pinched between the opposing surface of the opposing member and the rear surface of the second pulley main body and does not move.

According to the fourth aspect of the present invention, the second connecting means integrally connects the two pulleys to the rotary shaft via the first connecting means for integrally connecting the two pulleys so as to be integrally rotatable. The structure can be simplified as compared with the case where each pulley main body is individually connected to the rotating shaft. According to the fifth aspect of the present invention, since the diaphragm spring that connects the two pulley bodies so as to be integrally rotatable also serves as the elastic member, the structure can be simplified. In addition, since the diaphragm spring can directly urge both pulley main bodies, as a result of being able to displace both pulley main bodies smoothly,
A smooth shift can be achieved.

According to the sixth aspect of the present invention, for example, when a fluctuating load torque is applied, this load torque is converted into a force for bringing both pulley main bodies close to each other, so that the power transmission ring is sandwiched by both pulley main bodies. The clamping force can be increased. Thereby, it is possible to prevent the occurrence of slippage between the power transmission ring and the power transmission surface mainly composed of both pulleys.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a variable-diameter pulley included in an accessory driving device according to an embodiment of the present invention, showing a state where a power transmission ring is eccentric.

FIG. 2 is a schematic view of a main part of an accessory driving device including the variable diameter pulley of FIG. 1;

FIG. 3 is a graph showing a relationship between rotation speeds of a driving pulley and a variable diameter pulley of FIG. 1;

FIG. 4 is a sectional view showing a state in which a power transmission ring is concentric in the variable diameter pulley of FIG. 1;

FIG. 5 is a front view of a diaphragm spring of the variable diameter pulley of FIG. 1;

FIG. 6 is a schematic view showing a combined state of a connection hole and a connection shaft of a diaphragm spring of the variable diameter pulley of FIG. 1;

FIG. 7 is a partially cutaway perspective view showing a main part of an opposing member fixed to a second pulley main body in the variable diameter pulley of FIG. 1;

FIG. 8 is a cross-sectional view of a variable-diameter pulley included in an accessory driving device according to another embodiment of the present invention, showing a state where a power transmission ring is at a concentric position.

9 is a side view showing a part of an outer peripheral surface of a main body of a second pulley in the variable diameter pulley of FIG. 8;

FIG. 10 is a schematic view showing a second pulley main body, an opposing member, and a connecting shaft with a roller for connecting these members in the variable diameter pulley shown in FIG. 8, wherein (a) shows a state in which a power transmission ring is located at a concentric position; (B) corresponds to a state where the power transmission ring is eccentric.

[Explanation of symbols]

Reference Signs List A Variable diameter pulley B Auxiliary drive device 1 Rotary shaft 2 First pulley main body 3 Second pulley main body 4,5 Power transmission surface 6 Power transmission ring 7 Belt 11 Diaphragm spring (first coupling means, elastic member) 12 Connection part (second connection means) 13 Connection shaft (second connection means) 14 Inner diameter part 15 Outer diameter part 28 Back surface 43 Opposing surface 44 Opposing member 47 Inertia member 48 Housing space 49 Roller (rolling member) 55 Tensioner 56 Tensioner pulley 57 Elastic member A1 Variable diameter pulley 61 Rotary shaft 62 First pulley main body 63 Second pulley main body 64, 65 Power transmission surface 69 Opposing member 77 Back surface 80 Opposing surface 81 Housing space 82 Ball (inertial member, rolling member) 85 Compression coil spring (elastic member) 89, 90 Connecting shaft (first connecting means) 94 Connecting portion (second connecting means) 96 Brush 97 Roller 98,99 Guide groove 100,101 Cam surface T conversion mechanism (torque cam mechanism)

Claims (6)

[Claims] 1. A power transmission ring around which an endless belt is wound, a pair of pulley main bodies capable of eccentrically holding the power transmission ring and transmitting power to a rotating shaft of an auxiliary machine, and a main body of the pulley. A variable diameter pulley comprising: an elastic member for urging the power transmission ring to a concentric position, and an inertial member for energizing the pulley main body by centrifugal force while rotating with the pulley main body to urge the power transmission ring to the concentric position; A tensioner having an elastic member that applies tension to the belt via a tensioner pulley so as to urge the transmission ring toward the eccentric side; and the elastic member of the tensioner attempts to eccentrically move the power transmission ring through the belt. The position of the power transmission ring is regulated by the balance between the force and the force of the elastic member and the inertia member of the variable diameter pulley urging the power transmission ring to the concentric position. Accessory drive system, characterized in that the. 2. The variable-diameter pulley further includes an opposing member connected to the one pulley main body so as to be integrally movable in the axial direction and including an opposing surface opposing a back surface of a power transmission surface of the other pulley main body. 2. The accessory drive device according to claim 1, wherein the inertia member is accommodated in an accommodation space defined between an opposing surface of the opposing member and a back surface of the other pulley main body. 3. The accessory driving device according to claim 2, wherein the inertia member includes a rolling member that rolls on an opposing surface of the opposing member and a back surface of the second pulley main body. 4. The variable diameter pulley has first connecting means for connecting the two pulley bodies so as to be integrally rotatable, and connects the two pulley bodies to a rotary shaft via the first connecting means so as to transmit power. 4. The accessory driving device according to claim 1, further comprising a second connecting means. 5. The first connecting means includes a diaphragm spring whose inner and outer diameters are integrally rotatably engaged with corresponding pulleys, respectively, and the diaphragm spring also serves as the elastic member. The accessory drive device according to claim 4, wherein 6. The apparatus according to claim 4, wherein said second connecting means includes a pair of conversion mechanisms for converting the rotational angular displacement of each pulley main body with respect to the rotating shaft into axial displacements in opposite directions. Accessory drive.