JP4423560B2 - Power transmission chain and power transmission device including the same - Google Patents

Description

  The present invention relates to a power transmission chain and a power transmission device including the power transmission chain.

  In an endless power transmission chain used in a power transmission device such as a pulley type continuously variable transmission (CVT) of an automobile, links adjacent to each other in the chain traveling direction are formed by a pair of pin-shaped members. There exists what was connected with the connection member (for example, refer patent documents 1-3). Each link is formed with a pair of through holes, and a connecting member corresponding to each through hole is inserted therethrough. Along with the bending of the links, the pair of pin-shaped members of the corresponding connecting members roll with each other.

At this time, the pair of pin-shaped members are in rolling contact with each other on the contact portion so that the links are smoothly bent, and the position of the contact portion is changed along with the bending of the links. It is going to change.
Japanese Patent Laid-Open No. 8-31725 JP-A-7-167224 JP-A-1-169149

The power transmission chain is required to reduce noise during driving. Moreover, sufficient durability is required to withstand a large load.
Accordingly, an object of the present invention is to provide a power transmission chain that can reduce noise during driving and can improve practical durability, and a power transmission device including the power transmission chain.

In order to solve the above-described problems, the present invention provides a power transmission chain (1) including a plurality of links (2; 2A) and a plurality of connecting members (200; 3) that connect these links so as to bend each other. in each coupling member includes a predetermined power transmission member (3), a predetermined power transmission member is contraposition member (4) comprising a member (4) interposed between said predetermined power transmission member and the link or rolling and sliding contact with the bending between the links with respect to kinematic pair members (2 a) composed of the link (2A), the predetermined power transmission member is first specification member (31) and the second specification member (32), and the amount of movement of the contact point on the movement locus of the contact point (T) viewed from the chain width direction of the rolling sliding between the first specification member and the corresponding pair member associated with the bending between the links ( N1) is the first 2 The larger than the movement amount (N2) of the contact point on the movement locus of the contact point (T) seen from the chain width direction of the rolling sliding between the specification member and the corresponding pair member, the plurality of links have a connection pitch (PL) includes a long pitch link (25; 25A) having a relatively long length and a short pitch link (24; 24A) having a relatively short connection pitch (PS), each link having a chain traveling direction (X). The front through hole (9; 9A) and the rear through hole (10; 10A) arranged side by side before and after the connecting member corresponding to each through hole are inserted, and the front through hole of the short pitch link is short. The first specification member or the second specification member is inserted through the rear through hole of the pitch link and the front through hole of the long pitch link, respectively, and the second specification member is inserted through the rear through hole of the long pitch link. It is characterized by that That.

In addition, the alphanumeric characters in parentheses represent corresponding components in the embodiments described later. The same applies hereinafter.
For example, the power transmission chain is wound around a pulley or the like to constitute a part of the power transmission device, and power is transmitted between the connecting member and the pulley.
According to the present invention, by providing two types of power transmission members having different amounts of movement of the contact points due to the bending between the links, the period when each connecting member is sequentially engaged with the pulley is non-uniform. Can be. In addition, by providing two types of links having different connection pitches, it is possible to make the period when the respective connection members sequentially engage with the pulleys even more uneven. Thereby, the frequency of the engagement sound when each connecting member is sequentially engaged with the pulley can be distributed over a wide range, and the noise can be sufficiently reduced.

Here, when the corresponding links are bent at a predetermined bending angle from the straight state, the movement amount on the movement locus of the contact point of the first specification member is the movement amount of the contact point of the second specification member. Is greater than the amount of movement.
In addition, the connection pitch of the long pitch link is longer than the connection pitch of the short pitch link, so that the bending angle of the long pitch link with respect to a predetermined adjacent link when the power transmission chain is wound around the pulley and bent. Is larger than the bending angle of a short pitch link with respect to a predetermined adjacent link.

Therefore, if the first specification member is inserted into the rear through-hole of the long pitch link, the contact point of the first specification member moves too much (too close) to one side in the chain radial direction when the chain is bent. End up. As a result, there is a concern that a large load acts locally on a part of the peripheral edge of the rear through hole of the long pitch link, thereby hindering improvement in practical durability.
However, in the present invention, the second specification member is inserted into the rear through hole of the long pitch link. Since the second specification member has a smaller amount of movement of the contact point due to the bending between the links, the contact point of the power transmission member inserted into the rear through-hole of the long pitch link is the chain diameter when the chain is bent. It is possible to prevent being too close to one of the directions. Therefore, it can suppress that a big load is locally applied to a part of periphery of the through-hole of a long pitch link. As a result, the stress generated in the long pitch link can be reduced, and the practical durability of the power transmission chain can be improved.

  In this case, it is preferable that the first specification member is not inserted through the long pitch link from the viewpoint of improving the durability. In this case, the following can be illustrated as a combination of the link and the power transmission member that does not apply a large load locally. That is, a combination of inserting the first specification member through the short pitch link, a combination of inserting the second specification member through the short pitch link, and a combination of inserting the second specification member through the long pitch link can be exemplified.

The rolling sliding contact means a contact including at least one of a rolling contact and a sliding contact.
In the present invention, the long pitch link and the short pitch link may be randomly arranged in the chain traveling direction. In this case, the cycle when each connecting member is sequentially engaged with the pulley is randomized, and the frequency of the engagement sound when each connecting member is sequentially engaged with the pulley is distributed over a wider range. It can be further reduced.

In the present invention, the first specification member and the second specification member may be randomly arranged in the chain traveling direction. In this case, the cycle when each connecting member is sequentially engaged with the pulley is randomized, and the frequency of the engagement sound when each connecting member is sequentially engaged with the pulley is distributed over a wider range. It can be further reduced.
In the present invention, the long pitch link and the short pitch link are randomly arranged in the chain traveling direction, and the first specification member and the second specification member are randomly arranged in the chain traveling direction. There is.

In this case, the period when each connecting member is sequentially engaged with the pulley is made synergistically extremely random, and the frequency of the engagement sound when each connecting member is sequentially engaged with the pulley is made wider. Can be distributed. Thereby, noise can be further reduced.
In the present invention, the first and second pulleys (60, 70) each having a pair of conical surface sheave surfaces (62a, 63a, 72a, 73a) facing each other and the pulleys are wound around these pulleys. And the above power transmission chain that transmits power in contact with the sheave surface. In this case, a power transmission device excellent in silence and durability can be realized.

Preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 schematically shows a main configuration of a chain-type continuously variable transmission (hereinafter also simply referred to as a continuously variable transmission) as a power transmission device including a power transmission chain according to an embodiment of the present invention. It is a perspective view. Referring to FIG. 1, a continuously variable transmission 100 is mounted on a vehicle such as an automobile, and includes a drive pulley 60 made of metal (such as structural steel) as a first pulley, and a second pulley. And a driven pulley 70 made of metal (such as structural steel) and an endless power transmission chain 1 (hereinafter also simply referred to as a chain) wound between the pulleys 60 and 70. . In addition, the chain 1 in FIG. 1 has shown a partial cross section for easy understanding.

  FIG. 2 is a partially enlarged sectional view of the drive pulley 60 (driven pulley 70) and the chain 1 of FIG. Referring to FIGS. 1 and 2, drive pulley 60 is attached to input shaft 61 connected to a vehicle drive source so as to be capable of transmitting power, and includes fixed sheave 62 and movable sheave 63. Yes. The fixed sheave 62 and the movable sheave 63 have a pair of sheave surfaces 62a and 63a that face each other. Each sheave surface 62a, 63a includes a conical inclined surface. A groove is defined between the sheave surfaces 62a and 63a, and the chain 1 is held between the grooves 1 with a strong pressure.

  The movable sheave 63 is connected to a hydraulic actuator (not shown) for changing the groove width, and moves the movable sheave 63 in the axial direction of the input shaft 61 (left and right in FIG. 2) during shifting. By doing so, the groove width is changed. Thereby, the chain 1 is moved in the radial direction of the input shaft 61 (vertical direction in FIG. 2), and the effective radius R (hereinafter also referred to as the effective radius R of the pulley 60) of the pulley 60 is set to the minimum value R1. (See FIG. 3A. For example, 30 mm.) To a maximum value R2 (see FIG. 3B, for example, 70 mm.) Can be changed.

On the other hand, as shown in FIGS. 1 and 2, the driven pulley 70 is attached to an output shaft 71 that is connected to a drive wheel (not shown) so as to be capable of transmitting power and is integrally rotatable. A fixed sheave 73 and a movable sheave 72 each having a pair of opposed sheave surfaces 73a and 72a for forming a groove for sandwiching the chain 1 with high pressure are provided.
A hydraulic actuator (not shown) is connected to the movable sheave 72 of the driven pulley 70 in the same manner as the movable sheave 63 of the drive pulley 60, and the groove width is changed by moving the movable sheave 72 during shifting. It is like that. Accordingly, the chain 1 is moved, and the effective radius R of the pulley 70 related to the chain 1 (hereinafter also referred to as the effective radius R of the pulley 70) is changed from the maximum value R2 (see FIG. 3A) to the minimum value R1 (see FIG. 3). 3 (see (B)).

With the above configuration, when the continuously variable transmission 100 has the highest reduction ratio (under drive), the effective radius R of the drive pulley 60 is set to the minimum value R1, as shown in FIG. The effective radius R of the pulley 70 is set to the maximum value R2.
On the other hand, when the speed increasing ratio of the continuously variable transmission 100 is the highest (during overdrive), the effective radius R of the drive pulley 60 is set to the maximum value R2, as shown in FIG. The effective radius R is set to the minimum value R1.

FIG. 4 is a cross-sectional view of the main part of the chain 1. 5A is a cross-sectional view taken along the line II-II in FIG. 4, and FIG. 5B is a cross-sectional view taken along the line III-III in FIG. 4, each showing a linear region of the chain 1. ing. FIG. 6 is a side view of the bent region of the chain 1.
In the following description, the description will be made with reference to the linear region of the chain 1 when described with reference to FIG. 5, and the description will be made with reference to the bent region of the chain 1 when described with reference to FIG.

  Referring to FIGS. 4 and 5A, chain 1 includes a plurality of links 2 and a plurality of connecting members 200 that connect these links 2 so as to be able to bend each other. Each connecting member 200 includes a first pin 3 as a predetermined power transmission member and a second pin 4 as a power transmission member and a pair member paired therewith. The first pins 3 are in rolling contact with the second pins 4 that make a pair as the corresponding links 2 are bent.

The rolling sliding contact means a contact including at least one of a rolling contact and a sliding contact.
Hereinafter, a direction along the traveling direction of the chain 1 is referred to as a chain traveling direction X, and a direction perpendicular to the chain traveling direction X and along the longitudinal direction of the first and second pins 3 and 4 is defined as the chain width direction W. A direction perpendicular to both the chain traveling direction X and the chain width direction W is referred to as an orthogonal direction V.

Each link 2 is formed in a plate shape, and is disposed between a front end portion 5 and a rear end portion 6 as a pair of end portions arranged in the front and rear in the chain traveling direction X, and between the front end portion 5 and the rear end portion 6. An intermediate portion 7 is included.
The front end portion 5 and the rear end portion 6 are respectively formed with a front through hole 9 as a first through hole and a rear through hole 10 as a second through hole. The intermediate portion 7 has a column portion 8 that partitions the front through hole 9 and the rear through hole 10. The column portion 8 has a predetermined thickness in the chain traveling direction X. The peripheral edge of each link 2 is formed in a smooth curve and has a shape in which stress concentration hardly occurs.

  First to third link rows 51 to 53 are formed using the link 2. Specifically, each of the first link row 51, the second link row 52, and the third link row 53 includes a plurality of links 2 arranged in the chain width direction W. In each of the first to third link rows 51 to 53, the links 2 in the same link row are aligned so that the positions in the chain traveling direction X are the same. The first to third link rows 51 to 53 are arranged side by side along the chain traveling direction X.

The links 2 of the first to third link rows 51 to 53 are respectively connected to the links 2 of the corresponding first to third link rows 51 to 53 using the corresponding first and second pins 3 and 4. It is connected to bendable (relatively rotatable).
Specifically, the front through-hole 9 of the link 2 of the first link row 51 and the rear through-hole 10 of the link 2 of the second link row 52 correspond to each other side by side in the chain width direction W. The links 2 of the first and second link rows 51 and 52 are connected to be able to bend in the chain traveling direction X by the first and second pins 3 and 4 that pass through the through holes 9 and 10. Yes.

Similarly, the front through-hole 9 of the link 2 of the second link row 52 and the rear through-hole 10 of the link 2 of the third link row 53 correspond to each other along the chain width direction W. The links 2 of the second and third link rows 52 and 53 are connected to be able to be bent in the chain traveling direction X by the first and second pins 3 and 4 inserted through the through holes 9 and 10.
Although not shown, next, the links of the third and fourth link rows are connected to each other, and thus the links 2 of the two link rows adjacent in the chain traveling direction X correspond to each other. An endless chain 1 is formed by sequentially connecting the first and second pins 3 and 4.

The first pin 3 is a long (plate-like) predetermined power transmission member extending in the chain width direction W. The peripheral surface 11 of the first pin 3 extends in parallel to the chain width direction W.
The peripheral surface 11 is formed as a smooth surface, and includes a front portion 12 as a facing portion facing forward in the chain traveling direction X, a rear portion 13 as a back portion facing backward in the chain traveling direction X, and an orthogonal direction V. One end 14 and the other end 15 as a pair of opposite ends.

The front portion 12 faces the paired second pins 4 and comes into rolling contact with a rear portion 19 (to be described later) of the second pins 4 at a contact portion T (contact point as viewed from the chain width direction W). ing.
The rear portion 13 is formed on a flat surface. This flat surface has a predetermined inclination angle B with respect to a predetermined plane A orthogonal to the chain traveling direction X (a plane orthogonal to the paper surface in FIG. 5), and faces the inner peripheral side of the chain. .

The one end portion 14 constitutes an end portion on the chain outer peripheral side (one in the orthogonal direction V) of the peripheral surface 11 of the first pin 3 and is formed in a curved surface that is convexly curved toward the chain outer peripheral side. Yes.
The other end portion 15 constitutes an end portion on the chain inner peripheral side (the other in the orthogonal direction V) of the peripheral surface 11 of the first pin 3, and has a curved surface that is convexly curved toward the inner peripheral side of the chain. Is formed.
In the following, in the orthogonal direction V, a side from the one end portion 14 toward the other end portion 15 is referred to as a chain inner peripheral side, and a side from the other end portion 15 toward the one end portion 14 is referred to as a chain outer peripheral side.

The pair of end portions 16 in the longitudinal direction (chain width direction W) of the first pin 3 protrudes in the chain width direction W from the links 2 arranged at the pair of end portions in the chain width direction W, respectively. The pair of end portions 16 are respectively provided with end surfaces 17 as a pair of power transmission portions.
2 and 6, the pair of end faces 17 are opposed to each other across a plane orthogonal to the chain width direction W, and have a symmetrical shape. These end surfaces 17 are for frictional contact (engagement) with the corresponding sheave surfaces 62a, 63a, 72a, 73a of the pulleys 60, 70.

The first pin 3 is sandwiched between the corresponding sheave surfaces 62a, 63a, 72a, 73a, whereby power is transmitted between the first pin 3 and the pulleys 60, 70. Since the end surface 17 of the first pin 3 directly contributes to power transmission, the first pin 3 is formed of a high-strength wear-resistant material such as bearing steel (SUJ2), for example.
The end surface 17 of the first pin 3 is formed in a shape including a part of the spherical surface, and is convexly curved outward in the chain width direction W. The one end portion 14 of the first pin 3 is formed longer (wider) in the chain width direction W than the other end portion 15, whereby the end surface 17 faces the inner circumferential side of the chain. When viewed from the chain width direction W, the position of the top 23 of the end face 17 coincides with the position of the centroid of the end face 17.

A contact region 240 is provided on the end surface 17. The contact area 240 of the end surface 17 comes into contact with the corresponding sheave surfaces 62a, 63a, 72a, 73a of the pulleys 60, 70.
The contact region 240 has, for example, an elliptical shape, and has a contact center point C (corresponding to the centroid of the contact region 240). When viewed from the chain width direction W, the position of the contact center point C coincides with the position of the top 23 (the position of the centroid of the end face 17). The position of the contact center point C may be shifted (offset) from the centroid of the end surface 17.

Here, the effective radius R of each of the pulleys 60 and 70 described above is defined as follows. That is, the effective radius R of the drive pulley 60 is the diameter of the pulley 60 between the contact center point C of the power transmission surface 17 of the first pin 3 clamped by the drive pulley 60 and the center axis F1 of the drive pulley 60. Defined as direction distance.
Similarly, the effective radius R of the driven pulley 70 is such that the pulley 70 between the contact center point C of the power transmission surface 17 of the first pin 3 sandwiched by the driven pulley 70 and the center axis F2 of the driven pulley 70 is the same. Defined as radial distance.

When viewed from the chain width direction W, the long axis D of the contact region 240 has a predetermined angle of attack E (for example, 10 °) with respect to the plane A, and is directed from the chain outer periphery side toward the inner periphery side. Accordingly, the chain proceeds in the chain traveling direction X side.
The angle of attack E is, for example, equal to the inclination angle B of the rear portion 13 of the first pin 3 (E = B). The angle of attack E and the inclination angle B may be different from each other.

4 and 5A, the second pin 4 (also referred to as a strip or an interpiece) is formed of the same material as the first pin 3 and extends in the chain width direction W. It is a member of a scale (plate shape), and is a pair member as a member interposed between the corresponding first pin 3 and the corresponding link 2.
The second pin 4 is formed shorter than the first pin 3 so that the pair of end portions do not contact the sheave surfaces of the pulleys, and with respect to the first pin 3 that makes a pair, It is arranged in front of the chain traveling direction X. With respect to the chain traveling direction X, the second pin 4 is formed thinner than the first pin 3.

The peripheral surface 18 of the second pin 4 extends in the chain width direction W. The peripheral surface 18 is formed as a smooth surface, and includes a rear portion 19 as a facing portion facing backward in the chain traveling direction X, a front portion 20 facing forward in the chain traveling direction X, and a pair of orthogonal directions V. It has one end 21 and the other end 22 as end portions.
The rear portion 19 is formed on a flat surface orthogonal to the chain traveling direction X. As described above, the rear portion 19 faces the front portion 12 of the paired first pins 3.

The front portion 20 is formed on a flat surface substantially parallel to the rear portion 19.
The one end portion 21 constitutes an end portion on the chain outer peripheral side of the peripheral surface 18 of the second pin 4 and is formed in a curved surface that is convexly curved toward the chain outer peripheral side.
The other end portion 22 constitutes an end portion on the inner circumferential side of the peripheral surface 18 of the second pin 4 and is formed in a curved surface that is convexly curved toward the inner circumferential side of the chain.

  The chain 1 is a so-called press-fit type chain. Specifically, the first pin 3 is loosely fitted in the front through hole 9 of each link 2 so as to be relatively movable, and the relative movement is regulated by the rear through hole 10 of each link 2. The second pin 4 is press-fitted and press-fitted so that the relative movement of the second pin 4 is restricted to the front through-hole 9 of each link 2 and can be relatively moved to the rear through-hole 10 of each link 2. Are loosely fitted.

  In other words, the first pin 3 is loosely fitted in the front through hole 9 of each link 2 so as to be relatively movable, and the second pin 4 paired with the first pin 3 is relatively moved. The first pin 3 is press-fitted and fitted in the rear through hole 10 of each link 2 so that relative movement is restricted, and the first pin A second pin 4 paired with 3 is loosely fitted so as to be relatively movable.

With the above configuration, the rear portion 19 of the second pin 4 that forms a pair with the front portion 12 of the first pin 3 moves on the contact portion T along with the bending between the links 2 adjacent to each other in the chain traveling direction X. Rolling and sliding contact with each other.
Referring to FIG. 6, in the bending region of chain 1, link 2 is bent at a bending angle φ with respect to link 2 adjacent to the rear of chain traveling direction X. For example, the bending angle φ is defined as an angle formed by the first plane H1 and the second plane H2.

The first plane H1 includes the respective contact center points C of the pair of first pins 3a and 3b inserted into the respective through holes 9 and 10 of the link 2a in one of the bent regions, and the chain width. A plane parallel to the direction W.
The second plane H2 is inserted into each of the through holes 9 and 10 of the other link 2b adjacent to the rear of the link 2a in the chain traveling direction X. A plane including the contact center point C and parallel to the chain width direction W is referred to.

The range of the design bending angle φ (allowable bending angle) is set to 0 ° to 20 °, for example.
With reference to FIGS. 4, 5 (A) and 5 (B), the feature of this embodiment is that two types of links having different connection pitches are provided as links 2, Noise at the time of driving is reduced. Further, as the first pin 3, two kinds of members having different movement trajectories of the rolling sliding contact of the contact portion T are provided, and the noise at the time of driving the chain 1 is further increased. In addition, by optimizing the arrangement of these two types of links and the two types of members, the practical durability of the chain 1 is sufficiently secured.

Specifically, the link 2 includes a short pitch link 24 having a relatively short connection pitch and a long pitch link 25 having a relatively long connection pitch.
The short pitch link 24 has a predetermined connection pitch PS. The connection pitch PS refers to the distance between the adjacent first pins 3 in the short pitch link 24 in the linear region of the chain 1. Specifically, the mutual contact portion T1 of the first and second pins 3 and 4 in the front through-hole 9 of the short pitch link 24 in the straight region of the chain 1 and the rear through-hole 10 of the short pitch link 24. This is the distance in the chain traveling direction X between the first and second pins 3 and 4 and the contact portion T1 between them.

  The long pitch link 25 has a predetermined connection pitch PL. The connection pitch PL refers to the distance between the adjacent first pins 3 in the long pitch link 25 in the linear region of the chain 1. Specifically, the mutual contact portion T1 of the first and second pins 3 and 4 in the front through-hole 9 of the long pitch link 25 in the linear region of the chain 1 and the rear through-hole 10 of the long pitch link 25. This is the distance in the chain traveling direction X between the first and second pins 3 and 4 and the contact portion T1 between them.

The thickness of the column portion 8 of the long pitch link 25 in the chain traveling direction X is thicker than the thickness of the column portion 8 of the short pitch link 24 in the chain traveling direction X. Thereby, the connection pitch PL of the long pitch link 25 is longer (PL> PS) than the connection pitch PS of the short pitch link 24.
The first pin 3 includes a first specification member 31 and a second specification member 32. As will be described below, the first specification member 31 and the second specification member 32 have different shapes of the front portions 12 from each other.

The front portion 12 of the first specification member 31 has a curved surface portion 33. Of the front part 12 of the first specification member 31, the curved surface part 33 forms a contact part T, and the contact part T is in rolling contact with the rear part 19 of the second pin 4 forming a pair. .
An end of the curved surface portion 33 on the inner circumferential side of the chain is a predetermined starting portion J1 (predetermined starting point when viewed from the chain width direction W). When viewed from the chain width direction W, the position of the raised portion J1 coincides with the position of the contact portion T1, that is, the position of the contact portion T of the first specification member 31 (first pin 3) in the linear region of the chain 1. Yes. The raised portion J1 is disposed closer to the inner peripheral side of the chain in the front portion 12 of the first specification member 31.

When viewed from the chain width direction W, the curved surface portion 33 is composed of an involute curve as a predetermined curve having a predetermined starting portion J1 (starting point). The basic circle K1 of the involute curve is a circle having a center M1 and a radius Rb1 (basic circle radius, for example, 70 mm).
The center M1 is positioned on the chain inner peripheral side with respect to the contact portion T1 on a plane orthogonal to the chain traveling direction X and including the contact portion T1 of the first specification member 31. The basic circle K1 and the starting portion J1 intersect.

With the above configuration, the movement trajectory of the contact portion T of the first specification member 31 due to the bending between the corresponding links 2 is an involute having a starting portion J1 with respect to the first specification member 31 as viewed from the chain width direction W. It has a curve.
That is, when viewed from the chain width direction W, the curved surface portion 33 of the first specification member 31 is formed in an involute curve, so that the movement trajectory of the contact portion T becomes the above-described involute curve. The contact portion T is displaced on the outer peripheral side of the chain on the curved surface portion 33 as the bending angle between the corresponding links 2 increases.

In addition, you may form the shape seen from the chain width direction W of the curved surface part 33 of the 1st specification member 31 in shapes other than an involute curve, for example, the curve which has a 1 or several curvature radius.
The front portion 12 of the second specification member 32 has a curved surface portion 34. Of the front part 12 of the second specification member 32, the curved surface part 34 forms a contact part T, and the contact part T is in rolling contact with the rear part 19 of the second pin 4 making a pair. .

  The end of the curved surface portion 34 on the inner peripheral side of the chain is a predetermined starting portion J2 (predetermined starting point when viewed from the chain width direction W). When viewed from the chain width direction W, the position of the raised portion J2 coincides with the position of the contact portion T1, that is, the position of the contact portion T of the second specification member 32 (first pin 3) in the linear region of the chain 1. Yes. The raised portion J2 is disposed closer to the inner circumferential side of the chain in the front portion 12 of the second specification member 32.

When viewed from the chain width direction W, the curved surface portion 34 is composed of an involute curve as a predetermined curve having a predetermined starting portion J2 (starting point). The basic circle K2 of the involute curve is a circle having a center M2 and a radius Rb2 (basic circle radius, for example, 50 mm).
The center M2 is positioned on the chain inner peripheral side with respect to the contact portion T1 on a plane orthogonal to the chain traveling direction X and including the contact portion T1 of the second specification member 32. The basic circle K2 and the starting portion J2 intersect.

  When the straight region of the chain 1 is viewed from the chain width direction W, the raised portion J2 of the second specification member 32 and the raised portion J1 of the first specification member 31 are aligned in the orthogonal direction V. That is, these starting parts J2 and J1 are arranged on a predetermined straight line extending in the chain traveling direction X. In addition, these starting parts J2 and J1 may be arranged offset from each other in the orthogonal direction V.

The radius Rb2 of the base circle K2 of the second specification member 32 is smaller than the radius Rb1 of the base circle K1 of the first specification member 31 (Rb2 <Rb1).
With the above configuration, the movement trajectory of the contact portion T of the second specification member 32 due to the bending between the corresponding links 2 is an involute having a starting portion J2 with respect to the second specification member 32 as viewed from the chain width direction W. It has a curve.

That is, when viewed from the chain width direction W, the curved surface portion 34 of the second specification member 32 is formed in an involute curve, so that the movement trajectory of the contact portion T is set to the involute curve. The contact portion T is displaced on the outer peripheral side of the chain on the curved surface portion 34 as the bending angle between the corresponding links 2 increases.
In addition, you may form the shape seen from the chain width direction W of the curved surface part 34 of the 2nd specification member 32 in curves other than an involute curve, for example, the curve which has a 1 or several curvature radius.

  Referring to FIG. 6, when the corresponding links 2 in the linear region of the chain 1 are bent around the first specification member 31a so as to form a predetermined bending angle φ, the first specification associated with the bending is provided. The amount of movement of the contact portion T on the movement locus (curved surface portion 33a) of the rolling slide between the member 31a and the corresponding second pin 4a is a predetermined value N1 when viewed from the chain width direction W. Has been.

  On the other hand, when the corresponding links 2 in the linear region of the chain 1 are bent around the second specification member 32a so as to form a predetermined bending angle φ, they correspond to the second specification member 32a accompanying this bending. The amount of movement of the contact portion T on the movement trajectory (curved surface portion 34a) of the rolling contact with the second pin 4b is a predetermined value N2 when viewed from the chain width direction W.

As described above, since the radius of the base circle of the curved surface portion 33 is larger than the radius of the base circle of the curved surface portion 34, the movement amount N <b> 1 related to the first specification member 31 is the above-described amount related to the second specification member 32. It is larger than the movement amount N2 (N1> N2).
Referring to FIG. 7, a second specification member 32 is inserted as a first pin 3 into the rear through hole 10 of each long pitch link 25.

The first specification member 31 or the second specification member 32 is appropriately inserted as the first pin 3 into the rear through hole 10 of each short pitch link 24.
The first pin 3 that is inserted in the front through hole 9 of each long pitch link 25 through the rear through hole 10 of the link 2 that is arranged adjacent to the front of the long pitch link 25 in the chain traveling direction X. Is inserted. That is, the first specification member 31 or the second specification member 32 is appropriately inserted as the first pin 3 into the front through hole 9 of each long pitch link 25.

Similarly, the first through-holes 10 of the links 2 that are arranged adjacent to the front through-holes 9 of each short-pitch link 24 and adjacent to the front in the chain traveling direction X of the short-pitch link 24 are inserted. The pin 3 is inserted. That is, the first specification member 31 or the second specification member 32 is appropriately inserted as the first pin 3 into the front through hole 9 of each short pitch link 24.
The long pitch links 25 and the short pitch links 24 are randomly arranged in the chain traveling direction X. More specifically, at least one of the long pitch link 25 and the short pitch link 24 is irregularly arranged in at least a part of the chain traveling direction X.

For example, in the present embodiment, the first to fifth link rows 51 to 55 are configured by a long pitch link 25, a short pitch link 24, a long pitch link 25, a long pitch link 25, and a short pitch link 24, respectively. Has been.
The long pitch links 25 and the short pitch links 24 may be regularly arranged in the chain traveling direction X.

Further, the first specification member 31 and the second specification member 32 are randomly arranged in the chain traveling direction X. More specifically, at least one of the first specification member 31 and the second specification member 32 is irregularly arranged in at least a part of the chain traveling direction X.
For example, in the present embodiment, the second specification member 32 is inserted into the rear through hole 10 of the first link row 51, and the first specification is inserted into the rear through hole 10 of the second link row 52. The member 31 is inserted, the second specification member 32 is inserted into the rear through hole 10 of the third link row 53, and the second specification is inserted into the rear through hole 10 of the fourth link row 54. The member 32 is inserted, and the first specification member 31 is inserted into the rear through hole 10 of the fifth link row 55.

The first specification member 31 and the second specification member 32 may be regularly arranged in the chain traveling direction X.
The above is the schematic configuration of the continuously variable transmission. 3A, when driving continuously variable transmission 100, chain 1 is rotationally driven to transmit power to drive pulley 60 and driven pulley 70, respectively. At this time, the linear region of the chain 1 is shifted to the bending region by the first pin 3 engaging with one of the pulleys 60 and 70, and the bending region of the chain 1 is the first pin 3. When the engagement with the corresponding pulleys 60 and 70 is released, the region moves to the linear region. Thus, the chain 1 repeats the transition from the straight region to the bent region and the transition from the bent region to the straight region.

In the bending region of the chain 1, the bending angle φ of the long pitch link 25 with respect to a predetermined link (for example, the short pitch link 24) adjacent to the rear in the chain traveling direction X is, for example, the bending angle φ1.
On the other hand, the bending angle φ of the short pitch link 24 with respect to a predetermined link (for example, the short pitch link 24) adjacent to the rear in the chain traveling direction X is, for example, the bending angle φ2. At this time, the bending angle φ1 of the long pitch link 25 is larger than the bending angle φ2 of the short pitch link 24 (φ1> φ2).

  According to the present embodiment, since the first specification member 31 and the second specification member 32 are provided as the first pins 3, the first pins 3 are sequentially engaged with the pulleys 60 and 70. The period can be non-uniform. Further, by providing the long pitch link 25 and the short pitch link 24 as the link 2, the period when the first pins 3 are sequentially engaged with the pulleys 60 and 70 is made more uneven. Can do. Thereby, the frequency of the engagement sound when each first pin 3 is sequentially engaged with the pulleys 60 and 70 can be distributed over a wide range, and the noise can be sufficiently reduced.

Here, the movement amount N1 on the movement locus of the contact portion T of the first specification member 31 when the corresponding links 2 are bent at a bending angle φ from the linear state is the contact portion of the second specification member 32. It is larger than the movement amount N2 on the movement locus of T (N1> N2).
Further, the connecting pitch PL of the long pitch link 25 is longer than the connecting pitch PS of the short pitch link 24, so that the long pitch link 25 is bent when the chain 1 is wound around the pulleys 60 and 70 and bent. The angle φ1 is larger than the bending angle φ2 of the short pitch link 24.

  Therefore, if the first specification member 31 is inserted into the rear through-hole 10 of the long pitch link 25, the contact portion T of the first specification member 31 moves to the outside in the chain radial direction when the chain is bent (on the outer side of the chain). Move too much (too close). As a result, there is a concern that a large load acts locally on a part of the periphery of the rear through-hole 10 of the long pitch link 25 and hinders improvement in practical durability.

  However, in the present embodiment, the second specification member 32 is inserted into the rear through hole 10 of the long pitch link 25. In the second specification member 32, the amount of movement of the contact portion T accompanying the bending between the corresponding links 2 is smaller than that in the case of the first specification member 31. For this reason, even if the bending angle φ2 of the long pitch link 25 is large, the contact portion T of the first pin 3 (second specification member 32) inserted through the rear through hole 10 of the long pitch link 25 is not bent when the chain is bent. It is possible to prevent the chain from being too close to the outer side in the chain radial direction (outer side of the chain).

Therefore, it is possible to prevent a large load from being locally applied to the chain outer peripheral side portion of the peripheral edge of the rear through hole 10 of the long pitch link 25. As a result, the stress generated in the long pitch link 25 can be reduced, and the practical durability of the chain 1 can be improved.
In addition, by arranging the long pitch link 25 and the short pitch link 24 in the chain traveling direction X at random, the period when the first pins 3 are sequentially engaged with the pulleys 60 and 70 is random. Thus, the frequency of the engagement sound when the first pins 3 are sequentially engaged with the pulleys 60 and 70 can be distributed over a wider range. Thereby, noise can be reduced more.

  Further, by randomly arranging the first specification member 31 and the second specification member 32 in the chain traveling direction X, the period when the first pins 3 are sequentially engaged with the pulleys 60 and 70 is randomized. In this way, the frequency of the engagement sound when the first pins 3 are sequentially engaged with the pulleys 60 and 70 can be distributed over a wider range. Thereby, noise can be reduced more.

Further, the long pitch link 25 and the short pitch link 24 are randomly arranged in the chain traveling direction X, and the first specification member 31 and the second specification member 32 are randomly arranged in the chain traveling direction X. .
Thereby, the period when each first pin 3 is sequentially engaged with the pulleys 60 and 70 is made synergistically extremely random, and each first pin 3 is sequentially engaged with the pulleys 60 and 70. The frequency of the engagement sound at the time of doing can be distributed over a wider range. Thereby, noise can be further reduced.

Further, the first pin 3 is loosely fitted into the front through hole 9 of each link 2 and is press-fitted into the rear through hole 10 of each link 2. Further, the second pin 4 is fitted to the front through hole of each link 2. The link 9 is press-fitted and fitted into the rear through-hole 10 of each link 2.
Thereby, when each end surface 17 of each first pin 3 comes into contact with the corresponding sheave surface 62a, 63a, 72a, 73a of each pulley 60, 70, the second pin 4 that makes a pair has the first The links 2 can be bent by rolling and sliding contact with the pins 3.

At this time, between the first and second pins 3 and 4 that make a pair, the rolling contact component is large and the sliding contact component is very small. As a result, each end face 17 of each first pin 3 is The corresponding sheave surfaces 62a, 63a, 72a, and 73a come into contact with little rotation, so that friction loss can be reduced and higher transmission efficiency can be ensured.
Further, in each first pin 3, the locus of the contact portion T with respect to the first pin 3 draws an involute curve when viewed from the chain width direction W. Thereby, when each 1st pin 3 is sequentially bitten by each pulley 60 and 70, it can suppress that a string vibration-like motion arises in the chain 1. FIG. As a result, noise during driving of the chain 1 can be further reduced. Thus, the continuously variable transmission 100 excellent in silence, durability, and transmission efficiency can be realized.

In the present embodiment, as shown in FIG. 5A, the first specification member 31 may be inserted as the first pin 3 into the rear through hole 10 of each short pitch link 24.
In this case, the first specification member 31 having a large amount of movement of the contact portion T accompanying the bending between the corresponding links 2 is inserted into the rear through hole 10 of the short pitch link 24 having a small bending angle φ2.
Thereby, the movement amount of the contact part T of the 1st pin 3 (1st specification member 31) penetrated by the rear through-hole 10 of the short pitch link 24 can be decreased, and the said contact part T approaches the chain outer peripheral side. It can be suppressed. As a result, it is possible to suppress the occurrence of a large load locally on the outer peripheral side of the chain at the periphery of the rear through-hole 10 of the short pitch link 24, and the durability of the chain 1 can be further improved.

FIG. 8 is a partial cross-sectional view of the main part of another embodiment of the present invention. In the present embodiment, differences from the embodiment shown in FIGS. 1 to 7 are mainly described, and the same components are denoted by the same reference numerals and the description thereof is omitted.
Referring to FIG. 8, the feature of the present embodiment is that the second pin 4 is eliminated and each connecting member is constituted by only a single first pin 3 as a predetermined power transmission member. It is in the point. The pair member that is in rolling contact with the first pin 3 is a link 2A, and the links 2A adjacent to each other in the chain traveling direction X are connected to each other so as to be bendable (relatively rotatable).

Specifically, the corresponding first pin 3 is loosely fitted in the front through hole 9A of each link 2A so as to be relatively movable, and the corresponding first pin 3 is relative to the rear through hole 10A of each link 2A. It is press-fitted so that movement is restricted.
A front portion 41 (opposing portion) of the peripheral edge portion 40 of the front through hole 9A in the chain traveling direction X has a cross-sectional shape extending in the orthogonal direction V. The front portion 41 faces the front portion 12 of the first pin 3 loosely fitted in the front through hole 9A. The first pin 3 is in rolling contact with the front portion 41 at the contact portion T. Thereby, when viewed from the chain width direction W, the movement locus of the contact portion T with respect to the first pin 3 forms an involute curve.

According to the present embodiment, it is possible to further increase the number of first pins 3 to be bitten by each pulley at a shorter connection pitch between the first pins 3. Thereby, the load per 1st pin 3 can be reduced, the collision force with each pulley can be reduced, and noise can be reduced more.
While several embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, in the embodiment shown in FIGS. 1 to 7, the first pin 3 may be loosely fitted in the corresponding rear through hole 10 of each link 2.

The second pin 4 may be loosely fitted in the corresponding front through hole 9 of each link 2. Further, the second pin 4 may be engaged with the pulleys 60 and 70. Further, the shape of the curved surface portions 33 and 34 of the first specification member 31 and the second specification member 32 of the first pin 3 may be interchanged with the shape of the rear portion 19 of the paired second pin 4.
Further, in the embodiment shown in FIG. 8, the first pin 3 may be loosely fitted in the rear through hole 10A of each link 2A. Moreover, you may interchange the shape of the curved surface parts 33 and 34 of the 1st specification member 31 of the 1st pin 3, and the 2nd specification member 32, and the shape of the front part 41 of the link 2A which makes a pair.

  Furthermore, in each said embodiment, it is preferable from the point of durability improvement that the 1st specification member is not penetrated by the long pitch link. In this case, the following can be illustrated as a combination of the link and the power transmission member that does not apply a large load locally. That is, a combination of inserting the first specification member through the short pitch link, a combination of inserting the second specification member through the short pitch link, and a combination of inserting the second specification member through the long pitch link can be exemplified.

Moreover, you may use combining the 1st pin which has the curved surface part which consists of an involute curved surface, and the 1st pin which has a curved surface part which consists of curved surfaces other than an involute curved surface.
Moreover, the member which has the power transmission surface similar to the end surface of the said 1st pin is arrange | positioned in the vicinity of each of a pair of edge part of the longitudinal direction of a 1st pin, and it has a 1st pin and the said power transmission surface A power transmission block including a member may be provided and used as a predetermined power transmission member.

Further, the arrangement of the front through hole and the rear through hole of the link may be interchanged. Further, a communication part (slit) may be provided in the column part between the front through hole and the rear through hole of the link so that the front through hole and the rear through hole form one hole. In this case, the elastic deformation amount (flexibility) of the link can be increased, and the stress generated in the link can be further reduced.
Further, the present invention is not limited to a mode in which the groove widths of both the drive pulley 60 and the driven pulley 70 are changed, and only one of the groove widths may be changed and the other may be a fixed width that does not change. good. In the above description, the groove width is continuously (stepless) changed. However, the groove width may be changed stepwise or may be applied to other power transmission devices such as a fixed type (no shift). .

Examples and Comparative Examples Corresponding links were connected using first and second pins, and an example in which a second specification member was inserted into the rear through hole of each long pitch link was produced. Moreover, the corresponding link was connected using the 1st and 2nd pin, and the comparative example which penetrated the 1st specification member to the rear through-hole of each long pitch link was produced.

Durability tests were conducted on the examples and comparative examples. Specifically, each of the example and the comparative example is wound around a pulley to form a continuously variable transmission as shown in FIG. 1, and a constant torque is applied to rotate each of the example and the comparative example. The number of repetitions (rotation speed) until breakage was measured.
The test results are shown in FIG. As shown in FIG. 9, the example shows a value that is twice or more that of the comparative example. Thus, it was demonstrated that the examples were excellent in durability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view schematically showing a main configuration of a chain type continuously variable transmission as a power transmission device including a power transmission chain according to an embodiment of the present invention. It is a partial expanded sectional view of the drive pulley (driven pulley) and chain of FIG. It is typical sectional drawing of a continuously variable transmission, (A) has shown the state by which the effective radius of the drive pulley was made into the minimum while the effective radius of the driven pulley was made into the maximum, (B) is a drive pulley. The effective radius of the driven pulley is maximized and the effective radius of the driven pulley is minimized. It is sectional drawing of the principal part of a chain. (A) is sectional drawing which follows the II-II line of FIG. 4, (B) is sectional drawing which follows the III-III line of FIG. 4, Each has shown the linear area | region of the chain 1. FIG. It is a side view of the bending area | region of a chain. It is a fragmentary sectional view of the principal part for demonstrating the arrangement | sequence of a link and a 1st pin. It is a partial cross section figure of the principal part of another embodiment of this invention. It is a graph which shows the result of an endurance test.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Chain (power transmission chain), 2 ... Link, 2A ... Link (pair member), 3 ... 1st pin (connection member, predetermined power transmission member), 4 ... 2nd pin (between links) 9, 9A ... front through hole, 10, 10A ... rear through hole, 24, 24A ... short pitch link, 25, 25A ... long pitch link, 31 ... first specification member, 32 ... first 2 specification members, 60 ... drive pulley (first pulley), 70 ... driven pulley (second pulley), 62a, 63a, 72a, 73a ... sheave surface, N1, N2 ... moving amount, 200 ... connecting member, PL , PS: Connection pitch, T: Contact part (contact point) X: Chain travel direction

Claims (5)

In a power transmission chain comprising a plurality of links and a plurality of connecting members that connect these links so as to be bendable,
Each connecting member includes a predetermined power transmission member,
The predetermined power transmission member is in rolling contact with the pair of members made of a member interposed between the predetermined power transmission member and the link , or the pair of members made of the link, along with the bending between the links,
The predetermined power transmission member includes a first specification member and a second specification member,
The amount of movement of the contact point on the movement locus of the contact point seen from the chain width direction of the rolling sliding between the first specification member and the corresponding pair member accompanying the bending between the links is the second specification accompanying the bending between the links. It is larger than the amount of movement of the contact point on the movement locus of the contact point when viewed from the chain width direction of the rolling sliding between the member and the corresponding pair member,
The plurality of links include a long pitch link having a relatively long connection pitch and a short pitch link having a relatively short connection pitch,
Each link has a front through hole and a rear through hole arranged side by side in the chain traveling direction, and a connecting member corresponding to each through hole is inserted,
The first specification member or the second specification member is inserted into the front through hole of the short pitch link, the rear through hole of the short pitch link, and the front through hole of the long pitch link, respectively.
A power transmission chain, wherein a second specification member is inserted into a rear through hole of a long pitch link.   2. The power transmission chain according to claim 1, wherein the long pitch link and the short pitch link are randomly arranged in the chain traveling direction.   2. The power transmission chain according to claim 1, wherein the first specification member and the second specification member are randomly arranged in the chain traveling direction.   In Claim 1, the said long pitch link and the short pitch link are arranged at random in the chain advancing direction, and the said 1st specification member and the 2nd specification member are arranged at random in the chain advancing direction. A characteristic power transmission chain.   A first and a second pulley each having a pair of conical sheave surfaces facing each other and wound between these pulleys to transmit power in contact with the sheave surfaces. A power transmission device comprising the power transmission chain according to claim 4.

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