JP2004301257A - Power transmitting chain and power transmission using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmitting chain capable of effectively controlling the generation of noise. <P>SOLUTION: The power transmitting chain 1 comprises a plurality of links 2, and a plurality of pins 3A and 3B connecting the plurality of links 2. The chain 1 is used to be built between first and second pulleys, and brought into sliding contact between end faces 3a and 3b of the pins 3A and 3B and sheave surfaces of the first and second pulleys. The distance between contact positions is set to be random by using the plurality of pins 3A and 3B in which positions in contact with the sheave surfaces are different inside the end faces of the pins. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power transmission chain used for a so-called chain-type continuously variable transmission employed in a vehicle and the like, and a power transmission device using the same.
[0002]
[Prior art]
As a continuously variable transmission (CVT: Continuously Variable Transmission) of an automobile, for example, a drive pulley provided on an engine side, a driven pulley provided on a drive wheel side, and a plurality of links bridged between the two. And an endless chain having a plurality of pins interconnecting them. In such a so-called chain type continuously variable transmission, traction is generated by a slight sliding contact between the conical sheave surface of each pulley and the pin end surface of the chain in the circumferential direction of the sheave surface. To transmit power. Then, by continuously changing the groove width (distance between sheave surfaces) of at least one of the drive pulley and the driven pulley, a stepless speed change can be performed with a smooth motion different from the conventional gear type. .
[0003]
In the above-described chain-type continuously variable transmission, an unpleasant contact sound (metallic sound) is generated when the pin end surface of the bridged chain enters the sheave surface of each pulley or separates from the sheave surface. The end face of the pin constituting the chain is substantially in the longitudinal direction (radial direction of the pulley) of the pin end face in order to prevent a local increase in contact stress (edge load) near the edge of the pin end face. The same processing is applied to form an arc surface (full crowning shape) or the like set to a predetermined curvature in the same direction to form the same shape, and all the links constituting the chain are also formed to the same shape. Therefore, there is a problem that resonance of the contact sound occurs and loud noise is generated. To solve this problem, the distance between adjacent pin end faces (hereinafter, also referred to as "pitch") is made random by changing the length of the link constituting the chain and the position of the through hole into which the pin is inserted, A technique for suppressing the generation of loud noise caused by the resonance of a contact sound has been proposed (for example, see Patent Document 1).
[0004]
[Patent Document 1]
JP-A-5-202991 (page 2)
[0005]
[Problems to be solved by the invention]
However, in the above-described technique, many types of links must be manufactured to manufacture one chain. For this reason, there are problems such as the production of the link being complicated and the inability to use a common assembly jig for assembling the chain. For this reason, the above technology is not necessarily the best noise suppression measure, and development of a new technology is desired.
[0006]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a power transmission chain capable of effectively suppressing generation of noise and a power transmission device using the same. Furthermore, it is possible to provide a power transmission chain and a power transmission device using the same, in which the production of the link and the pin is not complicated, the assembling jig used for assembling the chain can be shared, and the assembling can be easily performed. Aim.
[0007]
[Means for Solving the Problems]
The power transmission chain of the present invention includes a plurality of links and a plurality of pins interconnecting the links, a first pulley having a conical sheave surface, and a second pulley having a conical sheave surface. A power transmission chain that is used by being bridged between a pulley and an end surface of the pin and a sheave surface of the first and second pulleys is in contact with each other to transmit power, wherein the plurality of pins are It is characterized by comprising two or more types of pins having different contact positions with the sheave surface in the pin end surface, and disposing these pins so that the distance between the contact positions of adjacent pins is random.
According to the above configuration, a plurality of pins having different positions in contact with the sheave surface within the pin end surface are used, and the pitch is irregular so as not to have a constant interval or a periodic pitch. The occurrence of resonance of the contact sound generated when entering and exiting the space is suppressed, and the generation of loud noise is suppressed. Further, when only the end face of the pin is processed, the manufacturing cost can be reduced.
[0008]
In the above power transmission chain, it is preferable that all of the plurality of links have substantially the same outer shape, and the plurality of pins have substantially the same shape except for the pin end faces. In this case, the production of the pins and links does not become complicated, and the jig for assembling the chains can be shared, and the assembling can be performed easily, so that the manufacturing and assembling costs can be suppressed. The reason why they are substantially the same is to take into account the occurrence of an unavoidable dimensional error in manufacturing.
[0009]
In the power transmission chain described above, it is preferable that the contact position between the pin end surface and the sheave surface is formed by providing the pin end surface with a curvature in at least two directions. In this case, since the contact area with the sheave surface is small, generation of noise is more effectively suppressed. Further, when the curvature is provided from two directions, that is, a direction substantially the same as the longitudinal direction of the pin end surface (radial direction of the pulley) and a direction different from that direction, a local increase in contact stress near the edge of the pin end surface ( Edge load) can be suppressed, and the generation of noise can be suppressed more effectively.
[0010]
The power transmission device according to the present invention includes a first pulley having a conical sheave surface, a second pulley having a conical sheave surface, and a first pulley having a conical sheave surface. A power transmission device comprising: a plurality of pins each having an end surface that is in sliding contact with a sheave surface of a pulley; and a chain having a plurality of links connected to each other by the pins. It is a power transmission chain.
According to the above configuration, the resonance of the contact sound generated when the pin end surface enters and exits between the sheave surfaces is effectively suppressed, so that no loud noise is generated. Therefore, when used as a continuously variable transmission for a vehicle or the like, the interior of the vehicle can be made a comfortable space and can contribute to the elimination of the vehicle noise problem. Further, when the plurality of links have substantially the same outer shape, and the plurality of pins have substantially the same shape excluding the pin end faces, the manufacturing and assembling costs are reduced. As a result, inexpensive products can be provided.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view schematically showing a main part configuration of a chain for a so-called chain type continuously variable transmission (hereinafter, also simply referred to as “chain”) according to an embodiment of the power transmission chain of the present invention. The chain 1 according to the present embodiment is endless and has a plurality of metal (bearing steel or the like) links 2 and a plurality of metal (bearing steel or the like) pins 3A and 3B for connecting the links 2 to each other. And a strip 5 slightly shorter than the pins 3A and 3B. Note that, in FIG. 1, a description of a link or a pin substantially at the center in the width direction of the chain 2 is partially omitted.
[0012]
The link 2 has a shape in which the outline is a gentle curve, two through holes 4 are provided for each sheet, and all are formed to have substantially the same outline. The through-hole 4 is configured so that the pin 3 and the strip 5 can be press-fitted therein, and the inner peripheral surface thereof is formed so as to be able to substantially adhere to the side surface of the pin 3 and the side surface of the strip 5. The links 2 are arranged in a predetermined order in parallel with the width direction of the chain 1 and are connected to be able to bend in the longitudinal direction of the chain 1.
[0013]
Each of the pins 3A and 3B is a rod-like body having a side surface extending along the inner peripheral surface of the through hole 4, and the shape of the portion excluding the pin end surface is formed to be substantially the same.
As shown in FIG. 2 (a), the pin 3A has an arc surface set to a predetermined curvature in a direction substantially the same as the radial direction of the pulley 8 which is the contacting member (a direction substantially the same as the longitudinal direction of the pin). It is formed in. As shown in FIG. 2 (b), the arcuate surface having a predetermined curvature is also formed in a direction substantially the same as the circumferential direction of the pulley 8 which is a contacting member (direction substantially the same as the width direction of the pin). ing. Thereby, one vertex on the pin end face 3a is located substantially at the center of the pin end face 3a in the longitudinal direction (substantially at the center in FIG. 2A) and slightly on the edge side in the width direction (slightly upper side in FIG. 2B). ), And this vertex becomes a contact position with the sheave surface (a portion that is substantially in point contact).
On the other hand, as shown in FIG. 3A, the pin 3B has a predetermined curvature in a direction substantially the same as the radial direction of the pulley 8 which is a contacting member (a direction substantially the same as the longitudinal direction of the pin), similarly to the pin 3A. It is formed on the set arc surface. Also, as shown in FIG. 3B, the vertex position different from the vertex position of the pin 3A is also substantially the same as the circumferential direction of the pulley 8 which is the contacting member (the direction substantially the same as the width direction of the pin). Is formed on an arc surface set to a predetermined curvature. Thereby, one vertex on the pin end face 3b is located substantially at the center of the pin end face 3b in the longitudinal direction (substantially at the center in FIG. 3A) and slightly on the edge side in the width direction (slightly lower in FIG. 3B). Side), and the apex is a contact position with the sheave surface (a portion that is substantially in point contact).
[0014]
The pins 3A and 3B are irregularly arranged so that the distance (pitch) between the contact positions of the pin end faces in the circumferential direction of the chain 1 is slightly different in order to effectively suppress the generation of noise accompanying the resonance of the unpleasant contact sound. Placed in That is, although the pitch is almost the same in the circumferential direction of the chain 1, the pins 3A and 3B are arranged so that the pitch differs by an amount based on the difference in the apexes (contact positions) in the end faces. For example, as shown in FIG. 4, the pins 3A, 3B, 3A, 3A, 3A, 3B, 3B are arranged in order from the left. In this arrangement, the pitches (distances between the contact positions) L1, L2, L3, L4, L5, and L6 are, in order, slightly longer, slightly shorter, middle, middle, slightly longer, and middle. The resonance of the contact noise generated by the contact between the pin end surface and the sheave surface is effectively suppressed. In the present invention, the arrangement of the pins 3A and 3B is not limited to the above order.
[0015]
The strip 5 is a rod-like body having a side surface along the inner peripheral surface of the through hole 4 and formed to be slightly shorter than the pins 3A and 3B so as not to come into contact with the sheave surface, and all have substantially the same shape. It is a thing. The strip 5 is pressed into the through hole 4 so that the side surface thereof rolls and slides (rolling contact or sliding contact or contact including both contacts) with the side surfaces of the pins 3A and 3B. As a result, the pins 3A and 3B hardly rotate with respect to the sheave surface of the pulley. For this reason, friction loss is reduced, and high power transmission efficiency can be secured.
[0016]
In the power transmission chain according to the present embodiment configured as described above, the distance (pitch) between the contact positions of the pin end surfaces is made slightly different by using different contact positions in the pin end surfaces. It is possible to suppress generation of loud noise due to resonance of the contact sound caused by contact with the surface. Also, only the pin end face needs to be processed, and since the pins and links having the same shape except for the pin end face are used, it is possible to use a common assembly jig. It becomes something.
[0017]
In the above, the case where the pin 3A shown in FIGS. 2A and 2B and the pin 3B shown in FIGS. 3A and 3B are used has been described, but the present invention is not limited to this. is not. For example, as shown in FIG. 5, one end of the pin end face in the width direction is an arc surface 3c having a predetermined curvature, and the other end is formed as a slope 3d. 3B, which is formed on an arc surface set to a predetermined curvature) may be used instead of one of the pins 3A and 3B. As shown in FIG. 6, one end of the pin end surface in the width direction is an arc surface 3e having a predetermined curvature, a contact portion with the sheave surface 8 is a flat surface 3f, and the other end is an inclined surface 3g. The pin 3D (the longitudinal direction of the pin end face is formed in an arc surface set to a predetermined curvature similarly to the pins 3A and 3B) may be used instead of one of the pins 3A and 3B.
In addition, the present invention is not limited to an embodiment using two types of pins, and may use more types of pins. However, if many types of pins are used, the manufacturing of the pins becomes complicated and the manufacturing cost becomes high.Therefore, using a small number of types of pins and arranging them in an appropriate order to suppress generation of loud noise due to resonance of contact noise. Is preferred.
[0018]
The power transmission chain of the present invention can be suitably used for a power transmission device such as a so-called chain-type continuously variable transmission. Hereinafter, a case where the present invention is applied to a chain-type continuously variable transmission, which is a typical mode of use of the power transmission chain of the present invention, will be described with reference to the drawings.
[0019]
FIG. 7 is a schematic perspective view showing a main part configuration of a so-called chain-type continuously variable transmission (hereinafter, also simply referred to as “continuously variable transmission”) according to an embodiment of the power transmission device of the present invention. The continuously variable transmission according to this embodiment is mounted on, for example, an automobile, and has a metal (such as structural steel) drive pulley 10 as a first pulley and a metal (such as structural steel) driven as a second pulley. It has a pulley 20 and an endless chain 1 spanned therebetween. The cross section of the chain 1 in FIG. 7 is partially shown for easy understanding.
[0020]
8, drive pulley 10 is attached to input shaft 11 connected to the engine side so as to be integrally rotatable, and has fixed sheave 12 having a conical inclined surface 12a, and its inclined surface. And a movable sheave 13 having a conical inclined surface 13a arranged opposite to 12a. A groove is formed by the inclined surfaces 12a and 13a of these sheaves, and the chain 1 is held between the grooves by strong pressure. Further, a hydraulic actuator (not shown) for changing the groove width is connected to the movable sheave 13, and the groove width is changed by moving the movable sheave 13 in the left-right direction of FIG. Thereby, the chain 1 can be moved up and down in FIG. 8 to change the radius of the chain 1 around the input shaft 11.
[0021]
On the other hand, the driven pulley 20 is integrally rotatably attached to the output shaft 21 connected to the drive wheel side, and has an inclined surface for forming a groove for sandwiching the chain 1 with high pressure, similarly to the drive pulley 10. A fixed sheave 22 and a movable sheave 23 are provided. A hydraulic actuator (not shown) is connected to the movable sheave 23 of the pulley 20 in the same manner as the movable sheave 13 of the drive pulley 10. , And thereby the chain 1 can be moved to change the winding radius of the chain 1 around the output shaft 21.
[0022]
The chain 1 bridged between the drive pulley 10 and the driven pulley 20 is the above-described power transmission chain (see FIGS. 1 to 4). Since the details are as described above, the description is omitted.
[0023]
In the continuously variable transmission according to the present embodiment configured as described above, for example, a stepless speed change can be performed as follows. That is, when the rotation of the output shaft 21 is decelerated, the groove width on the drive pulley 10 side is enlarged by moving the movable sheave 13, and the pin end surfaces 3a, 3b of the chain 1 are directed inward of the conical sheave surfaces 12a, 13a. While the sliding diameter of the chain 1 around the input shaft 11 is reduced while making sliding contact under boundary lubrication conditions (downward in FIG. 8), the groove width is reduced by moving the movable sheave 23 on the driven pulley 20 side. While the pin end surfaces 3a and 3b of the chain 1 are in sliding contact with the conical sheave surfaces 22a and 23a outwardly under boundary lubrication conditions, the winding diameter of the chain 1 around the output shaft 21 is increased. By doing so, the rotation of the output shaft 21 can be reduced. On the other hand, when increasing the rotation of the output shaft 21, the groove width on the drive pulley 10 side is reduced by moving the movable sheave 13, and the pin end surfaces 3 a, 3 b of the chain 1 are placed outside the conical sheave surfaces 12 a, 13 a. In the driven pulley 20 side, the groove width is increased by moving the movable sheave 23 while the sliding diameter of the chain 1 around the input shaft 11 is increased while slidingly contacting the chain 1 in the direction (upward in FIG. 8) under boundary lubrication conditions. Then, while the pin end faces 3a and 3b of the chain 1 are in sliding contact with the conical sheave surfaces 22a and 23a inward under boundary lubrication conditions, the diameter of the chain 1 wound around the output shaft 21 is reduced. By doing so, the rotation of the output shaft 21 can be increased.
[0024]
Since the continuously variable transmission according to this embodiment uses the above-described chain 1, generation of loud noise accompanying resonance of contact noise between the pin end surface and the sheave surface is effectively suppressed. Therefore, when used in a vehicle or the like, the interior of the vehicle can be made a comfortable space and can contribute to the solution of the vehicle noise problem.
[0025]
Note that the power transmission device of the present invention is not limited to a mode in which both the groove widths of the drive pulley and the driven pulley fluctuate, and only one of the groove widths fluctuates, and the other has a fixed width that does not fluctuate. It may be an aspect which did. In the above description, the mode in which the groove width changes continuously (steplessly) has been described. However, the present invention can be applied to other power transmission devices such as a stepwise change or a fixed type (no speed change). Good.
[0026]
【The invention's effect】
As described above, according to the power transmission chain of the present invention, the distance between the contact positions of the adjacent pins is made random by using a plurality of pins having different positions in contact with the sheave surface in the pin end faces. Generation of loud noise due to resonance of the unpleasant contact sound is effectively suppressed. Further, when the outer shapes of the plurality of links are all substantially the same and the shapes of the plurality of pins excluding the pin end faces are all substantially the same, the manufacture of the pins and links does not become complicated, Since the assembling is facilitated, manufacturing and assembling costs can be suppressed, and as a result, there is an advantage that inexpensive products can be provided.
[Brief description of the drawings]
FIG. 1 is a perspective view schematically showing a main configuration of a chain for a chain-type continuously variable transmission according to an embodiment of a power transmission chain of the present invention.
FIG. 2A is a cross-sectional view of the chain type continuously variable transmission chain shown in FIG. 1 in a direction substantially the same as the longitudinal direction of one pin 3A, and FIG. It is sectional drawing of the substantially same direction.
3A is a cross-sectional view of the chain type continuously variable transmission chain shown in FIG. 1 in a direction substantially the same as the longitudinal direction of another pin 3B, and FIG. It is sectional drawing of the same direction.
FIG. 4 is a plan view of the chain-type continuously variable transmission chain shown in FIG. 1 as viewed from a pin end surface side.
FIG. 5 is a sectional view in the pin width direction showing another example of a pin.
FIG. 6 is a sectional view in the pin width direction showing still another example of a pin.
FIG. 7 is a perspective view schematically showing a main part configuration of a chain-type continuously variable transmission according to an embodiment of the power transmission device of the present invention.
8 is a partially enlarged sectional view of a drive pulley (driven pulley) and a chain of the chain-type continuously variable transmission shown in FIG.
[Explanation of symbols]
1 Chain type continuously variable transmission chain (power transmission chain)
2 Link 3A, 3B Pin 3a, 3b Pin end face 5 Strip L1 to L6 Pitch (distance between contact positions)

Claims (4)

A first pulley having a conical sheave surface and a second pulley having a conical sheave surface, comprising a plurality of links and a plurality of pins interconnecting the links; A power transmission chain for transmitting power by contacting an end surface of the pin with a sheave surface of the first and second pulleys,
The plurality of pins are composed of two or more pins having different contact positions with the sheave surface in the pin end surface,
A power transmission chain wherein these pins are arranged so that the distance between the contact positions of adjacent pins is random. The power transmission chain according to claim 1, wherein the plurality of links have substantially the same outer shape, and the plurality of pins have substantially the same shape excluding a pin end surface. The power transmission chain according to claim 1, wherein the contact position between the pin end surface and the sheave surface is formed by providing the pin end surface with curvature in at least two directions. A first pulley having a conical sheave surface;
A second pulley having a conical sheave surface;
A chain having a plurality of pins that are bridged between the two and have an end surface that makes sliding contact with the sheave surfaces of the first and second pulleys, and a plurality of links that are interconnected by the pins; Power transmission device,
A power transmission device, wherein the chain is the power transmission chain according to any one of claims 1 to 3.

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