JP2013113432A - Continuously variable transmission mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a spring means from wearing and breaking due to displacement in a pulley axial direction and interference with a pulley center boss part, the spring means which biases a movable tooth with which a chain is meshed outward radially.SOLUTION: A movable tooth 17 in a pulley diameter direction is elastically supported in a radial limit position of (a) by a spring means 19 on an outer circumference of a pulley center boss part 16 between a fixed sheave 12_1 and a movable sheave 12a_2 to prevent slippage by engaging a chain 13 with the movable tooth 17. In a ratcheting state from a start of the engagement until an end of the engagement, and from complete engagement until release of the engagement, the spring means 19 displaces to the movable sheave 12a_2, and may wear and break by the interference with the pulley center boss part 16. In order to restrict axial displacement of the spring means 19, a stopper 17c is stood on a backside 17a of the movable tooth to prevent the spring means 19 from interfering with the pulley center boss part 16, and thereby the wear and breakage of the spring means 19 can be prevented.

Description

  The present invention comprises an endless chain link and a pulley around which the endless chain link is wound so as to be continuously variable, and is urged radially outward by a spring means around the outer periphery of the central boss of the pulley. The present invention relates to a continuously variable transmission mechanism capable of preventing slipping at a transmission ratio capable of meshing by meshing between a movable tooth provided so as to be able to advance and retract and a movable tooth meshing groove provided on an endless chain link. .

As this type of continuously variable transmission mechanism, a V-belt type continuously variable transmission is well known, and the endless chain link is stretched over the V groove of the pulley to enable power transmission,
By continuously changing the winding diameter of the endless chain link with respect to the pulley by changing the groove width of the pulley V groove during the power transmission, the continuously variable transmission can be performed.

On the other hand, as a technique for increasing the transmission efficiency by suppressing the slip of the continuously variable transmission mechanism, conventionally, as described in Patent Document 1, for example, teeth are projected on the outer peripheral surface of the central boss portion of the pulley that defines the bottom surface of the pulley V groove. Set up
While the tooth groove formed on the inner periphery of the endless chain link is in the transmission ratio that meshes with the teeth on the outer peripheral surface of the pulley center boss, the transmission efficiency of the continuously variable transmission mechanism is prevented by preventing slippage between the pulley and the endless chain link. A technique for improving the above has been proposed.

  On the other hand, in Patent Document 1, the teeth provided on the outer peripheral surface of the pulley central boss portion are configured as movable teeth that are urged radially outward by a spring means so as to be able to advance and retract in the radial direction. There has also been proposed a technique capable of preventing slippage at a transmission ratio meshed with a movable tooth meshing groove provided in a chain link.

According to this proposed technique, when the above-mentioned movable tooth fails to mesh with the inner peripheral tooth groove of the endless chain link, it can be retracted radially inward by the inner periphery of the endless chain link.
Since the teeth on the outer periphery of the pulley central boss part do not damage the endless chain link due to interference with the endless chain link, this is advantageous in terms of durability.

JP 2010-014269 A

  However, in the above-mentioned proposed technique, since the coil spring or the annular spring is used as the spring means for urging the movable tooth provided on the outer peripheral surface of the pulley center boss portion in the radial direction, the following problems are caused. Is produced.

When a coil spring is used as the spring means, the stroke of the coil spring required to generate the radially outward biasing force required by the movable tooth is large, and the coil spring is between the outer peripheral surface of the pulley center boss and the movable tooth. Is difficult to store.
However, when using a coil spring that fits in a space that can be secured between the outer peripheral surface of the pulley center boss and the movable tooth, it is difficult to generate the required spring force, and the movable tooth is required. Cannot be urged outward in the radial direction by the applied force.

  In order to earn a coil spring stroke, there is a method of reducing the shaft diameter of the pulley center boss, but this method has a problem in terms of durability due to insufficient shaft strength of the pulley center boss. .

On the other hand, when an annular spring is used as the spring means, a groove for escaping the annular spring is indispensable for the movable tooth, and the structure of the movable tooth becomes complicated and the cost increases.
After assembling the movable teeth first, the annular spring is assembled while being pressed against the movable teeth, and an elastic force is applied to the movable teeth, resulting in a problem that the workability of assembling the annular spring is poor.

  The present invention is a unique spring that does not cause the above-mentioned problem as a spring means for urging the movable teeth on the outer periphery of the pulley central boss portion radially outward, unlike a conventional coil spring or annular spring. The unique spring means is displaced in the pulley axis direction when the movable teeth are retracted inward in the pulley radial direction, and wears due to interference with the pulley central boss. It is an object of the present invention to provide a continuously variable transmission mechanism that does not break or break.

For this purpose, the continuously variable transmission mechanism according to the present invention is constituted as follows.
First, in order to explain the continuously variable transmission mechanism that is the basic premise of the gist configuration of the present invention,
It consists of an endless chain link and a pulley wrapped around this endless chain link so that it can be continuously variable,
Engagement of the movable teeth provided on the outer periphery of the central boss of the pulley by a spring means so as to be able to advance and retract in the radial direction and the movable teeth meshing groove provided in the endless chain link It is possible to prevent slip at a transmission ratio that can be

  The present invention is characterized in that the above-described spring means in the continuously variable transmission mechanism and the back surface of the movable tooth on which it is seated are particularly as follows.

First, the spring means comprises a U-shaped element interposed between the outer periphery of the central boss portion and the movable teeth while extending in the generatrix direction of the outer periphery of the central boss portion,
These U-shaped elements are oriented so that the opposing leg portions of the U-shaped element are seated on the outer periphery of the central boss portion at the mutual non-bonding ends, and the opposing leg portions are seated on the movable teeth at the mutual coupling ends. ,
The U-shaped elements are integrated with each other by connecting the adjacent leg portions of the adjacent U-shaped elements to each other with a connecting element other than a pair of adjacent leg portions at the non-bonding ends. The opposing leg portion of the U-shaped element is configured to apply the radially outward biasing force to the movable tooth at the mutual coupling end.

  The movable tooth has a stopper for limiting the displacement of the mutual coupling end of the U-shaped element when the movable tooth is retracted inward in the radial direction of the pulley on the back surface where the mutual coupling end of the U-shaped element is seated. The structure is standing up.

In such a continuously variable transmission mechanism of the present invention, among the U-shaped elements in which the mutual coupling ends are seated on the back surface of each movable tooth, adjacent leg portions of adjacent U-shaped elements, A unit of U-shaped elements obtained by integrating U-shaped elements with each other by connecting elements at non-bonding ends other than a pair of adjacent legs is used as a spring means for movable teeth. Because the opposing leg of the U-shaped element is configured to apply a radially outward urging force to the movable tooth at the mutual coupling end,
This spring means is a continuous body of a U-shaped element and a connecting element and becomes a torsion spring type spring means, and a large spring force can be generated with a relatively small spring stroke.

  Therefore, according to the present invention, it is possible to generate the radially outward biasing force required by the movable tooth with a small spring stroke, and even in a limited space between the pulley center boss outer periphery and the movable tooth, The spring means can be easily accommodated, and the movable teeth can be urged radially outward with a required force.

  Further, according to the present invention, since the required spring force can be generated with a small spring stroke as described above, it is not necessary to earn the spring stroke, and the shaft diameter of the pulley central boss portion needs to be reduced for the spring stroke. In addition, there is no problem of durability due to insufficient axial strength of the pulley center boss.

Further, according to the present invention, since the spring means is a continuous body of the U-shaped element and the connecting element, it is not necessary to provide the movable tooth with a groove for escaping these elements, and the structure of the movable tooth becomes complicated. There is no problem of high costs.
For the same reason, that is, since the spring means is a continuous body of the U-shaped element and the connecting element, this spring means can be assembled before the movable teeth are assembled to the outer periphery of the pulley center boss part, This is also very advantageous in terms of assembly workability.

In addition, according to the present invention, the displacement of the mutual coupling end of the U-shaped element is limited on the back surface of the movable tooth on which the mutual coupling end of the U-shaped element is seated when the movable tooth is retracted inward in the pulley radial direction. Because the stopper was erected,
Even if the above unique spring means is used, this unique spring means can limit the amount of displacement in the pulley axial direction when the movable teeth are retracted inwardly in the pulley radial direction. Durability can be improved by preventing wear or breakage due to interference with the boss portion.

1 is a schematic side view of a continuously variable transmission mechanism according to an embodiment of the present invention. FIG. 2 is a detailed view showing a slip prevention mechanism of a winding transmission portion on the secondary pulley side of the continuously variable transmission mechanism shown in FIG. Fig. 1 is an enlarged vertical side view of the main part showing the anti-slip mechanism between the endless chain link and the secondary pulley of the continuously variable transmission mechanism shown in Figs. 1 and 2, (a) is the movable teeth pushed inward in the pulley radial direction (B) is an enlarged vertical side view of the main part when the movable tooth is pushed inward in the radial direction of the pulley, (c) is a spring means for biasing the movable tooth. It is a principal part expansion vertical side view of the state in which ran on the opposing side wall of a movable tooth. FIG. 4 is a perspective view showing a secondary pulley center boss portion of the continuously variable transmission mechanism shown in FIGS. 1 to 3 in a state where a movable tooth biasing spring means is attached, but before the movable teeth are attached. 4 shows a movable tooth biasing spring means used in the continuously variable transmission mechanism of FIGS. 1 to 4, wherein (a) is an overall perspective view of the spring means, and (b) is the same spring relating to the VIII portion of (a). It is a partially enlarged detail perspective view of the means. FIG. 6 is an overall side view of the movable tooth biasing spring means shown in FIG. Fig. 3 shows a state where the movable pulley is attached to the center boss of the secondary pulley, (a) is a perspective view seen in the direction of arrow X in Fig. 3 (a), and (b) is seen in the direction of arrow Y in Fig. 3 (a). FIG. It is an expansion detailed perspective view which shows the back surface of the movable tooth on which the interconnection end of a spring means sits. It is a vector diagram for demonstrating the force which displaces a spring means to a pulley axial direction in the contact part of a spring means and a movable tooth back surface. (A) is an image diagram schematically showing the correlation between the endless chain link and the movable teeth, where (a) shows that the endless chain link is not yet in contact with the movable teeth, and the movable teeth are moved against the secondary pulley center boss by spring means. (B) is an image showing the lock-up state where the endless chain link is fully engaged with the movable tooth, and (c) is the set state and lock-up. It is an image figure which shows the ratcheting state of the transition period between states. FIG. 11 is an explanatory diagram showing changes between the states shown in FIGS. 10 (a), (b), and (c) in relation to a time-series change in pulley transmission ratio. 1 to 3 show the state of movable teeth attached to the secondary pulley center boss during high-frequency ratcheting of the continuously variable transmission mechanism shown in FIGS. 1 to 3, and (a) shows a certain angle in the direction of the arrow X in FIG. FIG. 3 (b) is a perspective view seen from another angle in the direction of arrow X in FIG. 3 (a).

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
<Configuration of Example>
1 to 6 show a continuously variable transmission mechanism according to an embodiment of the present invention, FIG. 1 is a schematic side view showing the entire continuously variable transmission mechanism 10, and FIG. 2 shows a winding on the secondary pulley side. It is detail drawing of a hanging transmission part.

In FIG. 1, 11 is a primary pulley that is a driving pulley of the continuously variable transmission mechanism 10, and 12 is a secondary pulley that is a driven pulley.
An endless chain link 13 is provided between the primary pulley 11 and the secondary pulley 12, and
The continuously variable transmission mechanism 10 can transmit power between the primary pulley 11 and the secondary pulley 12 via the endless chain link 13.

  Each of the primary pulley 11 and the secondary pulley 12 includes opposing sheaves 11a and 12a that face each other in the rotation axis direction (in FIG. 1, the sheave on the near side is removed and only the sheave on the other side is shown). A V-groove pulley having a pulley V-groove defined between 11a and opposed sheaves 12a, 12a.

As clearly shown in FIG. 2, the endless chain link 13 is formed in a continuous annular shape by connecting a large number of link plates 14 in a chain shape with link pins 15 in link pin insertion holes 14a at both ends.
Both end surfaces of each link pin 15 are inclined so as to come into surface contact with the inner side surface of the opposed sheave 11a and the inner side surface of the opposed sheave 12a that provide the pulley V groove side walls of the primary pulley 11 and the secondary pulley 12.

  Thus, the endless chain link 13 is clamped between the opposed sheaves 11a and 11a of the primary pulley 11 and the opposed sheaves 12a and 12a of the secondary pulley 12 in the pulley winding region, so that the primary pulley 11 and the secondary pulley Power transmission between 12 can be performed.

One of the opposed sheaves 11a of the primary pulley 11 is a fixed sheave, and the other is a movable sheave capable of stroke control in the axial direction.
As shown in FIGS. 3 (a) and 3 (b), the opposed sheave 12a of the secondary pulley 12 is a fixed sheave in which the sheave 12a_1 on the same side as the movable sheave of the primary pulley 11 is fixed to the pulley center boss portion 16, and the primary pulley 11 The sheave 12a_2 on the same side as the fixed sheave is spline-fitted to the pulley center boss portion 16 to form a movable sheave capable of stroke control in the axial direction.

As the movable sheave of the primary pulley 11 approaches the fixed sheave to narrow the pulley V groove width, the movable sheave 12a_2 of the secondary pulley 12 is moved away from the fixed sheave 12a_1 to widen the pulley V groove width.
The endless chain link 13 has an increased winding diameter with respect to the primary pulley 11 and a reduced winding diameter with respect to the secondary pulley 12, and the continuously variable transmission mechanism 10 is in the highest gear ratio selection state shown in FIGS. It is possible to upshift under a continuously variable transmission.

Conversely, as the movable sheave of the primary pulley 11 is moved away from the fixed sheave to increase the pulley V groove width, the movable sheave 12a_2 of the secondary pulley 12 is brought closer to the fixed sheave 12a_1 to narrow the pulley V groove width.
The endless chain link 13 has a reduced winding diameter with respect to the primary pulley 11 and an increased winding diameter with respect to the secondary pulley 12, and the continuously variable transmission mechanism 10 is shown in the state from the highest gear ratio selection state shown in FIG. It is possible to downshift under a continuously variable transmission toward a lowest gear ratio selection state not shown.

In order to improve the transmission efficiency of the continuously variable transmission mechanism 10 by suppressing the slip of the endless chain link 13 with respect to the secondary pulley 12 in the above-described highest gear ratio selection state of FIG. A plurality of movable teeth 17 are provided on the central boss portion 16 at regular intervals in the circumferential direction so as to protrude from the outer peripheral surface thereof.
These movable teeth 17 are guided in the pulley radial direction by a cylindrical movable tooth guide 18 provided on the outer peripheral surface of the secondary pulley central boss portion 16, and as shown in FIG. 3 (a), the fixed sheave 12a_1 of the secondary pulley 12 and The outward displacement in the pulley radial direction is limited by the inner peripheral surface 12b of the movable sheave 12a_2.

  Thus, the movable tooth 17 can advance and retreat in the radial direction within a limited range with respect to the outer peripheral surface of the secondary pulley central boss portion 16, but by the spring means 19 described in detail later, FIGS. As shown in a), it elastically supports the advance limit position protruding radially outward from the movable tooth guide 18.

The projecting tip of the movable tooth 17 meshes with the inner edge of each link plate 14 that defines the inner peripheral edge of the endless chain link 13 in the winding region of the secondary pulley 12 as shown in FIGS. A movable tooth meshing groove 14b for
By engaging the movable tooth 17 and the movable tooth meshing groove 14b, it is possible to suppress the slip of the endless chain link 13 with respect to the secondary pulley 12 in the highest gear ratio selection state, and to improve the transmission efficiency of the continuously variable transmission mechanism 10. it can.

  Therefore, when the movable tooth 17 is not aligned with the movable tooth meshing groove 14b and cannot be meshed with the movable tooth meshing groove 14b, the movable tooth 17 is resisted by the inner edge of the link plate 14 against the spring means 19 as shown in FIG. The retracted position can be pushed into the guide 18 so that the movable tooth 17 is not damaged by interference with the endless chain link 13.

<Details of spring means>
As shown in FIGS. 3 and 4, in this embodiment, a set of two spring means 19 for urging the movable teeth 17 in the movable tooth guide 18 radially outward on the outer periphery of the secondary pulley central boss portion 16 is provided. These spring means 19 are distributed in the longitudinal direction of the movable teeth 17, that is, in the axial direction of the secondary pulley central boss portion 16.
In this distributed arrangement, the spring means 19 is preferably distributed so as to equally apply a spring force in the longitudinal direction of the movable teeth 17.

All of the spring means 19 are the same, and have the following configuration described with reference to FIGS.
As shown in FIGS. 5 (a) and 6 as a whole, the spring means 19 in this embodiment has a linear U-shaped element 21 and a linear linear connecting element 22 alternately in the same circle. Arrange on the circumference to make an integrated unit.

The U-shaped element 21 is arranged between the outer periphery of the secondary pulley central boss part 16 and each movable tooth 17, that is, in the corresponding movable tooth receiving groove 18a of the movable tooth guide 18, toward the generatrix of the outer periphery of the central boss part. Intervene to extend.
Therefore, there are as many U-shaped elements 21 as movable teeth 17, and these U-shaped elements 21 have their opposing leg portions 21a seated on the outer periphery of the secondary pulley central boss portion 16 at the mutual non-bonding ends. The portion 21a is oriented so as to be seated on the movable tooth 17 at the mutual coupling end, and the orientation direction of the U-shaped element 21 is made the same by the two spring means 19.

All the U-shaped elements 21 are integrated with each other by connecting the adjacent leg portions 21a of the adjacent U-shaped elements 21 to each other by the connecting elements 22 at their non-bonding ends.
When integrating these U-shaped elements 21, the U-shaped elements 21 are inclined by an angle indicated by θ in FIG. 6 so that the mutual coupling ends of the opposed leg portions 21a are closer to the movable teeth 17 than the mutual non-coupling ends. Thus, it is assumed that the U-shaped element 21 exists in the shape of a Belleville spring over the entire circumference.
Thus, the spring means 19 becomes a continuous linear body composed of an alternating combination of the linear elements 21 and 22, and has a torsion spring type structure.

  By the way, the spring means 19 does not connect the adjacent leg portions 21a of the adjacent U-shaped elements 21 in the VIII portion of FIG. The portion 23 is formed in a C shape with a notch.

The C-shaped spring means 19 shown in FIGS. 5 and 6 as described above, in addition to setting the notch portion 23 in FIGS. In order to facilitate the assembly, the inner diameter in the free state is slightly larger than the outer diameter of the secondary pulley central boss portion 16.
Such C-shaped spring means 19 are made into a set of two, and each of them is expanded in the circumferential direction at the notch portion 23 in FIGS. 5 (a) and 5 (b), and the spring means 19 is connected in this expanded state. The element 22 is fitted into the corresponding circumferential groove 18b on the movable tooth guide 18 as shown in FIGS. 4 and 7 (a), 7 (b).
At this time, the two C-shaped spring means 19 are positioned in the circumferential direction such that the U-shaped element 21 is aligned with the movable tooth receiving groove 18a.

  After fitting the C-shaped spring means 19 to the outer peripheral surface (corresponding circumferential groove on the movable tooth guide 18) of the secondary pulley central boss portion 16, the inside of the movable tooth receiving groove 18a on the movable tooth guide 18 is obtained. The movable teeth 17 are inserted into the movable tooth guide 18 to complete the assembly of the spring means 19 and the movable teeth 17 to the movable tooth guide 18.

In this embodiment, as shown in FIGS. 3 (a), 3 (b), 7 (a), 7 (b) and FIG. 8, the back surface 17a of the movable tooth 17 on which the mutual coupling end of the U-shaped element 21 is seated. In addition, opposed side walls 17b are provided to rise inward in the radial direction of the pulley from both sides in the circumferential direction of the pulley with the mutual coupling end of the U-shaped element 21 interposed therebetween.
Each of these opposing side walls 17b is inclined so that the interval between these opposing side walls 17b increases toward the inside in the pulley radial direction, whereby the mutual coupling end of the U-shaped element 21 is separated from the back surface 17a of the movable tooth 17. When contacting the opposing side wall 17b, the opposing side wall 17b can guide the mutual coupling end of the U-shaped element 21 to a central position between the opposing side walls 17b.

  As shown in FIGS. 3 (a), (b), FIG. 7 (b), and FIG. 8, the movable tooth back surface 17a further includes the U-shaped elements 21 that are mutually retracted when the movable teeth 17 are moved backward in the pulley radial direction. Stoppers 17c are arranged to limit the displacement of the coupling end in the axial direction of the pulley (the same displacement of the spring means 19). These stoppers 17c have a height from the movable tooth back surface 17a. The height should be such that it protrudes inward.

  Here, the displacement in the pulley axial direction (displacement in the same direction of the spring means 19) of the mutual coupling end of the U-shaped element 21 when the movable tooth 17 is retracted inwardly in the radial direction of the pulley is schematically enlarged in detail in FIG. This will be described below.

The reaction force (-P) of the spring load (P) exerted on the movable tooth back surface 17a from the mutual coupling end of the U-shaped element 21 by the spring means 19 when the movable tooth 17 moves backward in the pulley radial direction, and the spring means 19 A direction perpendicular to the U-shaped element 21 that passes through the mutual coupling end of the U-shaped element 21 and is determined by the inclination angle α of the (U-shaped element 21) (the θ in the free state in FIG. 6 is changed) The force (-W) acting on
-W = (-P) / cosα
It is represented by

And by this force (-W), the component force F generated in the direction along the movable tooth back surface 17a is
F = (-W) x sin α
And
When the movable tooth 17 is retracted inward in the pulley radial direction, the mutual coupling end (spring means 19) of the U-shaped element 21 tends to be displaced in the pulley axial direction by this component force F.

  By the way, since there is a frictional resistance μF due to the spring load (P) between the mutual coupling end of the U-shaped element 21 and the movable tooth back surface 17a, the U-shape is retracted inward in the pulley radial direction. The mutual coupling end (spring means 19) of the element 21 is displaced in the direction toward the movable sheave 12a_2 (see FIG. 3) by the force of (F−μF).

Incidentally, the movable tooth 17 is restrained in the pulley axial direction by the secondary pulley central boss part 16 and the movable sheave 12a_2, and cannot move in the same direction, and when the movable tooth 17 is retracted inward in the pulley radial direction. In the case, the connecting element 22 between the adjacent U-shaped elements 21 appears to float in the fitting groove 18b, and no frictional resistance is generated between them.
Therefore, when the movable teeth 17 are retracted inwardly in the radial direction of the pulley, the mutual coupling ends (spring means 19) of the U-shaped element 21 are directed toward the movable sheave 12a_2 (see FIG. 3) by the force of (F−μF). It will be displaced in the axial direction.

  The displacement in the pulley axial direction of the mutual coupling end (spring means 19) of the U-shaped element 21 causes the spring means 19 (connection element 22) to collide with the edge portion 18c in the fitting groove 18b, and this interference. As a result, there arises a problem that the spring means 19 (the connecting element 22) is worn or broken due to damage, and in any case, a decrease in durability cannot be avoided.

In order to solve this problem, the stopper 17c erected on the movable tooth back surface 17a as described above has a mutual coupling end (spring means 19) of the U-shaped element 21 as the movable tooth 17 moves backward in the pulley radial direction. To limit the displacement of the pulley in the axial direction,
It goes without saying that the standing position of the stopper 17c with respect to the movable tooth back surface 17a is determined to be a position that can satisfy the above-mentioned requirements while preventing the operation of the continuously variable transmission mechanism.

<Effects of Example>
The spring means 19 as described above is assembled by inserting the movable tooth 17 into the movable tooth receiving groove 18a on the movable tooth guide 18 by appropriately setting the inclination angle θ of the U-shaped element 21 shown in FIG. At this time, the opposing leg 21a of the U-shaped element 21 is pushed inward in the radial direction by the movable teeth 17 at the mutual coupling ends, and the connecting element 22 is twisted and deformed.
Therefore, when the movable tooth 17 is assembled, the torsional reaction force of the connecting element 22 urges the movable tooth 17 radially outwardly within the movable tooth receiving groove 18a of the movable tooth guide 18, and the movable tooth 17 is normally movable. 3 (a) and 7 (a), (b) projecting radially outward from the movable tooth receiving groove 18a of the guide 18 can be elastically supported to realize the above-described slip prevention. obtain.

By the way, in the present embodiment, the spring means 19 for elastically supporting the movable tooth 17 at this position is provided with the U-shaped element 21 for each movable tooth 17 and the adjacent leg portions 21a of the adjacent U-shaped elements 21 mutually. Because it is composed of an alternating continuous body with connecting elements 22 that are connected to
The spring means 19 is of a torsion spring type, and a larger load (spring force) can be generated with a smaller spring stroke than when a coil spring or the like is used as in the prior art.

  Therefore, the radial outward urging force required by the movable tooth 17 can be generated with a small spring stroke, and even in the limited space between the outer periphery of the pulley center boss part 16 and the movable tooth 17, The spring means 19 can be easily accommodated, and the movable tooth 17 can be urged radially outward with a predetermined force.

  Further, according to the spring means 19 of the present embodiment, since the required spring force can be generated with a small spring stroke as described above, there is no need to earn a spring stroke, and the pulley central boss portion 16 of the pulley center boss portion 16 is used for the spring stroke. There is no need to reduce the shaft diameter, and there is no problem of durability due to insufficient shaft strength of the pulley center boss portion 16.

Further, according to this embodiment, since the spring means 19 is a continuous body of the U-shaped element 21 and the connecting element 22, it is not necessary to provide a groove for escaping these elements 21 and 22 in the movable tooth 17, and the movable means 17 is movable. There is no problem that the structure of the tooth 17 is complicated and the cost is increased.
For the same reason, that is, since the spring means 19 is a continuous body of the U-shaped element 21 and the connecting element 22, the spring means 19 assembles the movable teeth 17 on the outer periphery of the pulley center boss portion 16 as described above. It can be assembled in advance, which is very advantageous in terms of assembly workability.

Further, a plurality of (two) spring means 19 as described above are made into a set, and these spring means 19 are dispersedly arranged in the axial direction of the central boss portion 16 so that the plurality (two) of spring means 19 are U Because the movable tooth 17 is urged radially outward at the longitudinally equalized portion via the character element 21,
Even when the movable tooth 17 is a long object, the movable tooth 17 can be urged radially outwardly with a good balance in the longitudinal direction, and the movable tooth 17 can be prevented from coming into contact with each other.

Further, among the adjacent U-shaped elements 21, the pair of adjacent U-shaped elements is not formed by coupling the adjacent leg portions 21a with the connecting element 22, and the spring means 19 is formed into a C-shape with a notch 23. Because it was configured to
The spring means 19 is expanded in the circumferential direction at the C-shaped cutout 23, and in this state as shown in FIGS. 3 (a), (b), FIG. 4, FIG. 7 (a), (b), Since it can be fitted into the corresponding circumferential groove on the movable tooth guide 18, the assembly work of the spring means 19 is easy.

  Here, the process until the movable tooth meshing groove 14b of the link plate 14 forming the endless chain link 13 fully meshes with the movable tooth 17 during the upshift toward the highest (OD) pulley transmission ratio is reversed. In the following, the process until the movable tooth 17 is completely removed during the downshift from the highest (OD) pulley transmission ratio will be described.

FIG. 10 is an image diagram showing the correlation between the link plate 14 and the movable tooth 17. FIG. 10A shows the state before the upshift to the highest (OD) pulley transmission ratio. Is a state in which the link plate 14 is not shown in the drawing, that is, the movable tooth 17 is set to the radial protrusion limit position with respect to the secondary pulley center boss portion 16 by the spring means 19.
3 (a) and FIGS. 7 (a) and 7 (b) show a case where the movable tooth 17 is in the set state as in FIG. 10 (a).

  When an upshift to the highest (OD) pulley transmission ratio is performed, the fully engaged state (locked) in which the movable tooth engagement groove 14b of the link plate 14 is completely engaged with the movable tooth 17 as shown in FIG. 10 (b). Up state) EOD, and it is possible to prevent slip between the endless chain link 13 (link plate 14) and the secondary pulley 12 (center screw portion 16) at the highest (OD) pulley transmission ratio.

  In the pulley separation transmission ratio region immediately before the lock-up state EOD in FIG. 10 (b), the period from when the link plate 14 starts to contact the movable tooth 17 until the lock-up state in FIG. 10 (b) is reached. As shown in FIG. 10 (c), the link plate 14 pushes the movable teeth 17 inwardly in the pulley radial direction against the spring force of the spring means 19, but the movable teeth 17 move to the movable tooth meshing grooves 14b of the link plate 14. The so-called ratcheting state (chain pitch) in which a cycle allowing the movable teeth 17 to intrude into the movable teeth meshing groove 14b (return displacement of the movable teeth 17 outward in the pulley radial direction) is repeated. Override state) EOD IN.

  Note that the ratcheting state shown in FIG. 10 (c) is the process of switching from the lock-up state of FIG. 10 (b) to the set state of FIG. 10 (a) during the downshift from the highest (OD) pulley transmission ratio. In the same manner, the ratcheting state in this case is denoted by EOD OUT.

  When the above state change is illustrated in relation to the time series change of the pulley transmission ratio, as shown in FIG. 11, the solid line indicates the relationship between the set state of FIG. 10 (a) and the pulley transmission ratio, and the broken line indicates FIG. The relationship between the ratcheting state EOD IN or EOD OUT in c) and the pulley transmission ratio is shown, and the alternate long and short dash line shows the relationship between the lock-up state in FIG. 10 (b) and the pulley transmission ratio.

In the set state of FIGS. 3 (a) and 7 (a), (b), the movable teeth 17 are not pushed inwardly in the pulley radial direction against the spring means 19 by the link plate 14, so the spring means 19 is in the initial position at the beginning of assembly.
Therefore, the U-shaped element 21 is in contact with the back surface 17a of the movable tooth 17 at the center position between the opposing side walls 17b.

3 (b) and FIGS. 12 (a) and 12 (b) show the ratcheting state. In this case, the movable tooth 17 is repeatedly pushed inward in the pulley radial direction against the spring means 19 by the link plate 14. .
For this reason, the spring means 19 is torsionally elastically deformed while being reduced in diameter by repeated displacement of the mutual coupling ends inward in the radial direction of the pulley, and as shown in FIGS. 12 (a) and 12 (b), the spring means 19 The cutouts 23 overlap each other.

By the way, in the high frequency ratcheting state in which the movable teeth 17 are reciprocated and stroked frequently in the pulley radial direction due to high-speed rotation transmission, and the spring means 19 is repeatedly reduced in diameter at high frequency, the torsional elastic deformation of the spring means 19 is caused by the movable teeth 17 Thus, the interconnecting end of the spring means 19 that has been seated on the back surface 17a of the movable tooth 17 moves away from the movable tooth back surface 17a.
In this case, the spring means 19 is weakened in the circumferential restraining force and is easily displaced in the circumferential direction, and in particular, the interconnection end of the spring means 19 near the notch 23 is opposed to the movable tooth back surface 17a. It tries to come out of the groove defined between the side walls 17b.

However, at this time, in this embodiment, since the opposing side wall 17b of the movable tooth back surface 17a is an inclined surface having the above-described inclination angle, the spring means 19 is returned to the interconnection end of the spring means 19 into the groove between the movable tooth back surface opposing side wall 17b. Directional component force is applied, and the interconnecting ends of the spring means 19 act so as to be stopped in the groove between the movable tooth back surface opposite side walls 17b.
For this reason, the interconnecting end of the spring means 19 does not get out of the groove between the movable tooth back side opposing side walls 17b and gets on the opposing side walls 17b as shown in FIG. It is possible to avoid the adverse effect that the urging force of the movable tooth 17 becomes excessive and the durability is lowered, or the anti-slip action as planned cannot be obtained due to the spring means 19 itself.

  In the above-described ratcheting state, the U-shaped elements 21 are mutually connected when the movable teeth 17 are retracted inwardly in the pulley radial direction regardless of whether they are in a high-frequency ratcheting state or a low-frequency ratcheting state. The coupling end (spring means 19) is displaced in the pulley axial direction toward the movable sheave 12a_2 (see FIG. 3) by the force (F−μF) as described above with reference to FIG.

However, in this embodiment, the displacement of the mutual coupling end (spring means 19) of the U-shaped element 21 is limited by the stopper 17c as shown in FIG.
The spring means 19 (the connecting element 22) can be prevented from colliding with the edge portion 18c in the fitting groove 18b, and this interference causes the spring means 19 (the connecting element 22) to wear or break due to damage. It is possible to prevent the occurrence of a problem related to a decrease in durability.

As described above, the inclined opposing side wall 17b of the movable tooth back surface 17a causes the interconnecting end of the spring means 19 to disengage from the groove between the movable tooth back surface opposing side walls 17b and ride on this opposing side wall 17b as shown in FIG. However, even if the situation shown in Figure 3 (c) occurs for some reason,
In the present embodiment, since the stopper 17c has such a height that it protrudes inward in the pulley radial direction from the inclined opposed side wall 17b, it is possible to realize the solution of the above-described problems relating to wear and breakage of the spring means 19 (the connecting element 22).

That is, even in the situation of FIG. 3 (c), the displacement in the pulley axial direction of the mutual coupling end (spring means 19) of the U-shaped element 21 can be limited by the stopper 17c having the above-mentioned height as shown in FIG.
The spring means 19 (the connecting element 22) can be prevented from colliding with the edge portion 18c in the fitting groove 18b, and the spring means 19 (the connecting element 22) is worn or broken due to damage due to this interference. That is, it is possible to prevent the occurrence of the problem related to the decrease in durability.

<Other examples>
In the illustrated embodiment described above, the movable teeth 17 are provided on the central boss portion 16 of the secondary pulley 12 so as to prevent the slip between the endless chain link 13 and the secondary pulley 12 at the highest (OD) pulley transmission ratio. Although the idea of the present invention was applied for each installation,
The idea of the present invention can be similarly applied to the case where movable teeth are installed on the central boss portion of the primary pulley so as to prevent slippage between the endless chain link 13 and the primary pulley 11 at the lowest pulley transmission ratio. Of course, in this case as well, the above-described effects can be obtained.

10 Continuously variable transmission mechanism
11 Primary pulley
12 Secondary pulley
13 Endless chain link
14 Link plate
14a Link pin insertion hole
14b Movable tooth engagement groove
15 Link pin
16 Pulley center boss
17 movable teeth
17a Movable tooth back
17b Opposite inclined side wall
17c stopper
18 Movable tooth guide
18a Movable tooth receiving groove
18b Spring means fitting groove
18c Spring means fitting groove edge
19 Spring means
21 U-shaped element
21a Opposing legs
22 Connecting elements
23 Notch

Claims (2)

It consists of an endless chain link and a pulley wrapped around this endless chain link so that it can be continuously variable,
Engagement is achieved by meshing a movable tooth provided on the outer periphery of the central boss of the pulley so as to be able to advance and retreat in the radial direction by a spring means and a movable tooth meshing groove provided on the endless chain link. In a continuously variable transmission mechanism that enables slip prevention at a transmission ratio capable of
The spring means comprises a U-shaped element interposed between the outer periphery of the central boss portion and the movable tooth while extending in the generatrix direction of the outer periphery of the central boss portion,
These U-shaped elements are oriented so that the opposing leg portions of the U-shaped element are seated on the outer periphery of the central boss portion at the mutual non-bonding ends, and the opposing leg portions are seated on the movable teeth at the mutual coupling ends. ,
The U-shaped elements are integrated with each other by connecting the adjacent leg portions of the adjacent U-shaped elements to each other with a connecting element other than a pair of adjacent leg portions at the non-bonding ends. The opposing leg portion of the U-shaped element is configured to apply the radially outward biasing force to the movable tooth at the mutual coupling end,
On the back surface of the movable teeth on which the mutual coupling ends of the U-shaped elements are seated, a stopper is provided for limiting the displacement of the mutual coupling ends of the U-shaped elements when the movable teeth are retracted inwardly in the pulley radial direction. A continuously variable transmission mechanism characterized by being provided. The continuously variable transmission mechanism according to claim 1, wherein the movable tooth back surface is provided with opposing side walls that rise inward in the pulley radial direction from both sides of the pulley circumferential direction across the mutual coupling end of the U-shaped element.
The continuously variable transmission mechanism according to claim 1, wherein the stopper has a height from the back surface of the movable tooth so as to project inward in the pulley radial direction from the opposing side wall.

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