JP6428464B2 - Belt type continuously variable transmission for vehicles - Google Patents

Description

  The present invention relates to a belt-type continuously variable transmission for a vehicle, and more particularly to an improvement for suppressing a decrease in durability of the apparatus.

  2. Description of the Related Art A vehicular belt type continuously variable transmission including a transmission belt in which a plurality of elements are connected in a thickness direction along an endless annular ring and a pair of pulleys around which the transmission belt is wound is known. . For example, a pulley for a belt type continuously variable transmission described in Patent Document 1 is an example. In this technique, the side part of the element in the transmission belt and the contact surface of the pulley are configured to be brought into parallel contact with each other.

JP 2011-163511 A

  However, it is difficult to manufacture so that the side portions of the elements in the transmission belt and the contact surfaces of the pulleys can be brought into parallel with each other without any deviation. When a shift from parallel occurs in such a contact portion, a gap is generated between the element and the contact surface of the pulley. As a result, the posture of the transmission belt in the roll direction becomes unstable, and the durability of the apparatus may be reduced due to wear or the like.

  The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a belt type continuously variable transmission for a vehicle that suppresses a decrease in durability of the apparatus.

In order to achieve such an object, the gist of the present invention is that a transmission belt in which a plurality of elements are connected in a thickness direction along an endless annular ring, and a pair of pulleys around which the transmission belt is wound. A belt-type continuously variable transmission for a vehicle, wherein the element and a contact surface of the pulley are brought into contact with a radially outer side of the transmission belt at a side portion of the element to transmit power. A second portion that is spaced apart from the abutment surface when no change in posture in the roll direction occurs on the transmission belt on the radially inner side of the transmission belt at the side of the element. includes a shaped portion, the second shaped portion, the brought in parallel contact with the abutment surface when the posture change in the roll direction occurs in the transmission belt, those of the pulleys of the first shaped portion The contact area with respect to the surface is smaller than the contact area that is contacted in parallel with the contact surface of the pulley when the posture change in the roll direction of the element of the second shape portion occurs. When the posture change does not occur, the second shape portion prevents the second shape portion from coming into contact with the contact surface of the pulley even if the first shape portion is elastically deformed from the contact surface of the pulley. And the abutting surface of the pulley are set to be larger than the elastic deformation width of the first shape portion .

If it does in this way, it has the 1st shape part which contacts the contact surface in the element and the pulley, and transmits power in the diameter direction outside of the transmission belt in the side of the element, A second shape portion spaced apart from the abutting surface when the posture change in the roll direction is not generated in the transmission belt on the radially inner side of the transmission belt in the side portion; When the posture change in the roll direction occurs in the transmission belt, the part is brought into contact with the contact surface in parallel, so when the posture change in the roll direction occurs in the transmission belt, Since the element and the contact surface of the pulley are brought into parallel contact with each other, it is possible to suppress the posture of the transmission belt in the roll direction from becoming unstable. That is, it is possible to provide a belt type continuously variable transmission for a vehicle that suppresses a decrease in durability of the device. Further, the contact area of the first shape portion with the contact surface of the pulley is brought into contact with the contact surface of the pulley when the posture change of the element in the roll direction of the second shape portion occurs. If the contact area is smaller than the contact area and the posture change in the roll direction does not occur, even if the first shape portion is elastically deformed from the contact surface of the pulley, the second shape portion is not in contact with the pulley. Since the width between the second shape portion and the contact surface of the pulley is set larger than the elastic deformation width of the first shape portion so as not to contact the contact surface, the contact surface of the pulley The contact diameter of the transmission belt can be increased as much as possible, and the behavior of the transmission belt can be stabilized.

It is a figure explaining the composition of the belt type continuously variable transmission for vehicles to which the present invention is applied suitably. FIG. 2 is a front view for explaining in detail a configuration of an element provided in a transmission belt in the vehicle belt type continuously variable transmission of FIG. 1. FIG. 2 is a diagram for explaining in detail a configuration of a contact portion between an element and a pulley in the vehicle belt type continuously variable transmission of FIG. 1. FIG. 4 is a diagram illustrating a state in which the second shape portion of the element is brought into contact with the abutting surface of the pulley in the configuration of the present embodiment illustrated in FIG. FIG. 4 is a diagram illustrating a state in which the second shape portion does not contact the contact surface of the pulley even when elastic deformation occurs in the upper portion of the element in the configuration of the present embodiment illustrated in FIG. 3. It is a figure explaining the problem of the conventional vehicle belt-type continuously variable transmission for the comparison with a present Example.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the drawings used for the following description, the dimensional ratios and the like of each part are not necessarily drawn accurately.

  FIG. 1 is a diagram illustrating a configuration of a vehicle belt-type continuously variable transmission 10 (hereinafter simply referred to as a continuously variable transmission 10) to which the present invention is preferably applied. As shown in FIG. 1, the continuously variable transmission 10 includes an input-side pulley 12 and an output-side pulley 14 that have variable groove widths that are rotated around mutually parallel axes. A transmission belt 16 is wound between the input pulley 12 and the output pulley 14.

  The input-side pulley 12 includes an input-side fixed pulley 12a fixed to the input shaft 18 and an input-side movable pulley 12b attached so as to be movable in the axial direction of the input shaft 18. When the input side movable pulley 12b is moved in the axial direction of the input shaft 18 by the input side hydraulic actuator 20, the groove width between the input side fixed pulley 12a and the input side movable pulley 12b is changed. . The output-side pulley 14 includes an output-side fixed pulley 14 a fixed to the output shaft 22 and an output-side movable pulley 14 b attached so as to be movable in the axial direction of the output shaft 22. The output side movable pulley 14b is moved in the axial direction of the output shaft 22 by the output side hydraulic actuator 24, whereby the groove width between the output side fixed pulley 14a and the output side movable pulley 14b is changed. .

  A pair of conical input side sheave surfaces 12c that are closer to each other toward the center are formed on the opposing surfaces of the input side fixed pulley 12a and the input side movable pulley 12b that constitute the input side pulley 12. An input side V-groove 26 is formed between the input side fixed pulley 12a and the input side movable pulley 12b. A pair of conical output side sheave surfaces 14c that are closer to each other toward the center are formed on the opposing surfaces of the output side fixed pulley 14a and the output side movable pulley 14b that constitute the output side pulley 14. An output-side V-groove 28 is formed between the output-side fixed pulley 14a and the output-side movable pulley 14b. That is, in the present embodiment, the input-side sheave surface 12 c corresponds to a contact surface between the element 32 provided on the transmission belt 16 and the input-side pulley 12. The output sheave surface 14 c corresponds to a contact surface between the element 32 provided on the transmission belt 16 and the output pulley 14.

  The transmission belt 16 includes a pair of rings (hoops) 30 that are endless annular strip members. Along the pair of rings 30, a plurality of thick plate-like elements 32 are stacked in the thickness direction and bound in an annular shape. That is, the transmission belt 16 includes the plurality of elements 32 connected so as to be in close contact with each other in the thickness direction along the pair of rings 30, and is perpendicular to the plate thickness direction of the plurality of elements 32. That is, the pair of rings 30 is accommodated in a pair of grooves 34 opened on the side surface side. With this configuration, the transmission belt 16 has an endless annular configuration as a whole. The ring 30 is configured to have flexibility by, for example, laminating a plurality of endless annular thin plates made of, for example, steel having a uniform width dimension.

  When the groove width of the input side pulley 12 is changed by the input side hydraulic actuator 20, the transmission belt 16 wound around the input side pulley 12 is moved along the radial direction of the input side sheave surface 12c. It is done. Thereby, the effective diameter of the input pulley 12 is changed. At the same time, when the groove width of the output pulley 14 is changed by the output hydraulic actuator 24 in order to maintain the tension of the transmission belt 16, the transmission belt 16 wound around the output pulley 14 is It is moved along the output side sheave surface 14c. As a result, the effective diameter of the output pulley 14 is changed. In the continuously variable transmission 10, the speed ratio γ (= the rotational speed of the input pulley 12 / the rotational speed of the output pulley 14) is changed as described above.

  FIG. 2 is a front view for explaining in detail the configuration of the element 32 provided in the transmission belt 16. The side portions (side surfaces) 36 on both sides in the longitudinal direction of the element 32 where the pair of groove portions 34 are opened are the input sheave surface 12c in the input pulley 12 and the output in the output pulley 14. The side sheave surface 14c is contacted while facing each other. That is, in a state where the transmission belt 16 is wound between the input side pulley 12 and the output side pulley 14, the side portion 36 of the element 32 is at least a part of the side portion 36 as the contact surface. It is made to contact the input side sheave surface 12c and the output side sheave surface 14c. The pair of side portions 36 is also called a flank surface.

  FIG. 6 is a diagram for explaining problems of a conventional vehicle belt-type continuously variable transmission for comparison with the present embodiment. In the configuration shown in FIG. 6, parts common to the present embodiment are denoted by the same reference numerals and description thereof is omitted. In the conventional vehicular belt type continuously variable transmission 100 shown in FIG. 6 (hereinafter simply referred to as the continuously variable transmission 100), the transmission belt 102 includes a thick plate piece element 104 along the ring 30. A plurality of layers are stacked in the thickness direction and bound in an annular shape. The flank surfaces 106 that are both side surfaces of the element 104 in the width direction are configured to be in contact with the input sheave surface 12c and the output sheave surface 14c as contact surfaces substantially in parallel. That is, the flank surface 106 of the element 104 is a flat portion from the radially outer side to the inner side of the transmission belt 102, and the flat portion is substantially the input sheave surface 12c and the output sheave surface 14c. It is comprised so that it may become parallel. In other words, the flank angle, which is the inclination angle of the flank surface 106, is configured to be substantially equal to the inclination angles of the input sheave surface 12c and the output sheave surface 14c. In the present embodiment, the radial direction of the transmission belt 102 is a radial direction when the entire transmission belt 102 is viewed as a ring.

  In the conventional continuously variable transmission 100 configured as described above, as shown by the white arrow in FIG. 6, the transmission belt 102 is changed in posture in the roll direction, that is, the angle change in the width direction of the element 104 (rolling). ) Occurs, the durability of the apparatus becomes a problem. In the continuously variable transmission 100, the inclination angle (flank angle) of the flank surface 106 in the element 104 and the inclination angles of the input sheave surface 12c and the output sheave surface 14c coincide with each other without any deviation. Therefore, it is technically difficult to manufacture, and there is a considerable discrepancy between the two angles. When the flank surface 106, the input-side sheave surface 12c, and the output-side sheave surface 14c have an inclination angle mismatch, a part of the transmission belt 102 is part of the input-side sheave surface 12c or the output-side sheave surface 14c. Make a partial contact. When such uneven contact occurs, as shown in FIG. 6, a gap is generated between the transmission belt 102 and the input-side sheave surface 12c or the output-side sheave surface 14c, thereby causing the transmission belt 102 to move in the roll direction. The posture becomes unstable, and the durability of the transmission belt 102 may be reduced due to wear or the like.

  The problems in the conventional continuously variable transmission 100 become more prominent due to the narrowing of the V grooves in the input pulley 12 and the output pulley 14. That is, when it is considered that the angle tolerance between the flank surface 106, the input sheave surface 12c and the output sheave surface 14c does not change, the flank surface 106 and the input sheave surface are reduced by narrowing the surface angle. The influence of the angle error between 12c and the output sheave surface 14c tends to be relatively large. For example, when the angle tolerance is 1 (deg) and the surface angle (flank angle) is 11 (deg), the influence rate of the tolerance is 18%, but the angle tolerance is also 1 (deg) and the surface When the angle is 7 (deg), the tolerance influence rate is 29%. As described above, when the angle tolerance is set to be stationary and the surface angle is narrowed, a decrease in durability due to the deterioration of the posture of the transmission belt 102 becomes a problem. On the other hand, when the angle tolerance is reduced in terms of production technology to solve the above problem, it becomes technically difficult to avoid an increase in manufacturing cost.

  FIG. 3 is a diagram for explaining in detail the configuration of the contact portion between the element 32 and the input-side pulley 12 and the output-side pulley 14 in the continuously variable transmission 10 according to the present embodiment. It is the figure seen in the plate | board thickness direction of 32. In order to solve the problems in the conventional continuously variable transmission 100 described above, the continuously variable transmission 10 of this embodiment has a configuration as shown in FIG. That is, the element 32 and the input-side sheave surface 12c and the output-side sheave surface 14c as contact surfaces are brought into contact with the outer side in the radial direction of the transmission belt 16 at the side portion 36 of the element 32 to generate power. A first shape portion 38 to be transmitted is provided.

  As shown in FIG. 3, the continuously variable transmission 10 preferably has a side portion 36 of the element 32 that extends from a substantially central portion in the radial direction of the transmission belt 16 to an outer end portion of the transmission belt 16. A flat surface portion 40 having a surface angle α which is an angle based on the radial direction is provided. The first shape portion 38 preferably corresponds to a radially outer end portion of the transmission belt 16 in the side portion 36 of the element 32. In other words, it corresponds to the radially outer end of the transmission belt 16 in the flat portion 40. The inclination angle of the input-side sheave surface 12c or the output-side sheave surface 14c as a contact surface with respect to the radial direction of the transmission belt 16 is φ, and the surface angle α is larger than the inclination angle φ. The angle (α> φ). In the side portion 36, the range λ defined as the flat portion 40 is ½ or more of y (λ ≧ y), where y is the dimension (height dimension) of the side portion 36 in the radial direction of the transmission belt 16. / 2). In other words, in the side portion 36, a range λ from the radially inner side to the radially outer end of the transmission belt 16 in the radial direction is the flat surface portion 40.

  In the continuously variable transmission 10, the posture change in the roll direction is generated in the transmission belt 16 on the radially inner side of the transmission belt 16 (at least on the inner side of the flat portion 40) in the side portion 36 of the element 32. When there is not, it has the 2nd shape part 42 spaced apart from the said input side sheave surface 12c and the said output side sheave surface 14c as a contact surface. The second shape portion 42 corresponds to a plane portion having a plane angle ψ that is an angle with respect to the radial direction of the transmission belt 16. That is, in the continuously variable transmission 10, the side portion 36 has a range from the radially inner side to the radially inner end of the transmission belt 16 in the radial direction of the transmission belt 16. The second shape portion 42 is a plane portion in which the surface angle that is an angle with respect to the direction is ψ.

  FIG. 4 shows the relative positional relationship between the input-side sheave surface 12c or the output-side sheave surface 14c and the side portion 36 of the element 32 when the transmission belt 16 undergoes a posture change (rolling) in the roll direction. It is a figure explaining. As shown in FIG. 4, when the transmission belt 16 undergoes a change in posture in the roll direction, the second shape portion 42 includes the input-side sheave surface 12c and the output-side sheave surface that are contact surfaces. It is comprised so that it may contact in parallel with 14c. That is, as shown in FIG. 4, when the transmission belt 16 rolls at an angle θ, the second shape is set so that the input sheave surface 12c and the output sheave surface 14c are in contact with each other in parallel. A surface angle ψ of the portion 42 is determined. In other words, the surface angle ψ of the second shape portion 42 is the inclination angle φ of the input-side sheave surface 12c or the output-side sheave surface 14c and the posture change in the roll direction that is assumed to occur in the transmission belt 16. The sum (ψ = φ + θ) with the angle, that is, the rolling angle θ. Thereby, even when the posture change in the roll direction occurs in the transmission belt 16, the rolling amount of the transmission belt 16 can be minimized by bringing the second shape portion 42 into contact with the contact surface in parallel. Can be small.

  5 shows the relative position between the input sheave surface 12c or the output sheave surface 14c and the side portion 36 of the element 32 when elastic deformation occurs in the vicinity of the first shape portion 38 of the element 32. FIG. It is a figure explaining a relationship. As shown in FIG. 5, in the continuously variable transmission 10, even when elastic deformation occurs on the side portion 36 of the element 32 on the radially outer side of the transmission belt 16, a roll is applied to the transmission belt 16. When there is no change in orientation in the direction, the second shape portion 42 on the radially inner periphery side is configured not to contact the input sheave surface 12c or the output sheave surface 14c. . That is, the elastic deformation width of the element 32 in the vicinity of the first shape portion 38 is ε, and the width δ between the second shape portion 42 and the contact surface in the state where the elastic deformation does not occur is It is assumed that it is larger than the elastic deformation width ε (δ> ε).

  As described above, in the continuously variable transmission 10 according to the present embodiment, the first shape portion on the side surface 36 of the element 32 exclusively when the transmission belt 16 does not change in the roll direction. 38 is always in contact with the input-side sheave surface 12c and the output-side sheave surface 14c, which are contact surfaces, and the remaining part including the second shape portion 42 is not in contact with the contact surface. ing. With this configuration, the contact diameter of the transmission belt 16 with respect to the contact surface can be made as large as possible, and the behavior of the transmission belt 16 can be stabilized. When the posture change in the roll direction occurs in the transmission belt 16, the second shape portion 42 on the side surface 36 of the element 32 is brought into contact (that is, surface contact) in parallel with the contact surface. The amount of rolling of the transmission belt 16 can be made as small as possible, and the posture of the transmission belt 16 in the roll direction can be made stable. Furthermore, the range where relatively high accuracy is required is limited to the second shape portion 42, and the remaining portion of the side surface 36 has specifications that may be relatively low. 6 has the advantage that the required accuracy range is narrower than that of the conventional technology as described above, and the required accuracy can be easily realized and managed.

  According to the present embodiment, the input side as the contact surface of the element 32, the input side pulley 12, and the output side pulley 14 on the radially outer side of the transmission belt 16 at the side portion 36 of the element 32. A first shape portion 38 that transmits power by bringing the sheave surface 12c and the output-side sheave surface 14c into contact with each other is provided, and the transmission belt 16 is disposed radially inward of the transmission belt 16 on the side portion 36 of the element 32. When the posture change in the roll direction does not occur, the second shape portion 42 that is spaced apart from the contact surface is provided, and the second shape portion 42 causes the posture change in the roll direction to the transmission belt 16. If it occurs, the element is brought into contact with the abutting surface in parallel, and therefore when the posture change in the roll direction occurs in the transmission belt 16, the element Since 32 and the abutment surface of the input side pulley 12 and the output-side pulley 14 is brought into parallel contact can be suppressed roll direction of orientation of the transmission belt 16 becomes unstable. That is, the continuously variable transmission 10 that suppresses a decrease in durability of the device can be provided.

  The preferred embodiments of the present invention have been described in detail with reference to the drawings. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention. To be implemented.

  DESCRIPTION OF SYMBOLS 10: Belt type continuously variable transmission for vehicles, 12: Input side pulley, 12c: Input side sheave surface (contact surface), 14: Output side pulley, 14c: Output side sheave surface (contact surface), 16: Transmission Belt: 30: Ring, 32: Element, 36: Side part, 38: First shape part, 42: Second shape part

Claims (1)

In a belt type continuously variable transmission for a vehicle, comprising: a transmission belt in which a plurality of elements are connected in a thickness direction along an endless annular ring; and a pair of pulleys around which the transmission belt is wound.
A first shape portion that transmits power by bringing the element and a contact surface of the pulley into contact with each other on a radially outer side of the transmission belt in a side portion of the element;
A second shape portion that is spaced apart from the contact surface when the posture change in the roll direction is not generated in the transmission belt on the radially inner side of the transmission belt in the side portion of the element;
When the posture change in the roll direction occurs on the transmission belt, the second shape portion is brought into contact with the contact surface in parallel ,
The contact area of the first shape portion with respect to the contact surface of the pulley is a contact area that is brought into contact with the contact surface of the pulley in parallel when the posture change of the element in the roll direction of the second shape portion occurs. Is smaller than
When the posture change in the roll direction does not occur, the second shape portion does not contact the contact surface of the pulley even if the first shape portion receives elastic deformation from the contact surface of the pulley. A belt type continuously variable transmission for a vehicle, wherein a width between a second shape portion and a contact surface of the pulley is set larger than an elastic deformation width of the first shape portion .

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