JP5730180B2 - Belt for continuously variable transmission - Google Patents

Description

  The present invention relates to an element constituting a belt for a continuously variable transmission.

In a belt-type continuously variable transmission for a vehicle, a metal belt is wound between an input-side pulley to which engine rotational driving force is input and an output-side pulley connected to an output shaft.
In this belt type continuously variable transmission, the rotational width of the engine is changed at a desired gear ratio by changing the groove widths of the input pulley and the output pulley to change the belt winding diameter of both pulleys. It is transmitted to the output side.

  A belt of a belt-type continuously variable transmission is configured by sandwiching a large number of elements in an annular shape and sandwiching them between two sets of rings (for example, Patent Document 1).

Japanese Utility Model Publication No. 60-8545

FIG. 5 is a diagram for explaining a conventional belt 100. (A) is a perspective view of the belt 100, (b) is a front view of the element 102, and (c) is a portion where the element 102 is linearly arranged in the belt wound around the pulley. (D) is a figure which shows the part by which the element 102 was wound around the pulley and arrange | positioned in the curved form.
FIG. 6 is a diagram illustrating a state in which the belt 100 is wound around the input side pulley and the output side pulley, and is a diagram illustrating the compression side and the non-compression side of the belt 100. Here, the compression side refers to a portion where the element is compressed in the longitudinal direction of the belt by the rotational driving force transmitted from the input side pulley.

  As shown in FIG. 5 (a), the belt 100 is composed of an annular ring 101 formed by laminating a thin ring 101a made of a high-tensile steel plate, and a plate in which a large number of the rings 101 are arranged in the longitudinal direction of the ring 101. Element 102.

  As shown in FIG. 5B, the element 102 is connected to the wedge portion 103 having a saddle surface 103a on which the ring 101 slides on the upper surface, the head portion 104, and the wedge portion 103 and the head portion 104. And the element 102 in the belt 100 is restrained by a pair of rings 101 and 101 located on both sides of the connecting portion 105.

  As shown in FIG. 6, a belt 100 for a belt-type continuously variable transmission is provided by being wound around an input side pulley 111 to which engine torque is input and an output side pulley 112 that outputs torque.

  The input side pulley 111 and the output side pulley 112 are each constituted by a pair of fixed sheave and movable sheave, and the movable sheave moves in the axial direction of the pulley (the input side pulley 111 and the output side pulley 112), so that the input side The contact ratio between the pulley 111 and the output-side pulley 112 and the belt 100 is changed to change the gear ratio.

  In FIG. 6, in order to make it easy to see the relationship between the belt 100 and the pulleys (the input side pulley 111 and the output side pulley 112), the sheave on the front side of the sheet is omitted.

As shown in FIG. 6, the belt 100 wound around the input side pulley 111 and the output side pulley 112 has a compression side and an uncompression side of the element.
In the portion where the elements 102 on the compression side of the belt 100 are arranged in a straight line (for example, the region A in FIG. 6), as shown in FIG. 5C, each element 102 has a head 104 and a wedge portion 103. The contact surfaces of the element 102 are compressed in a state where the flat surfaces 104a and 106a of the contact portion 106 are brought into contact with the head 104 of the element 102 and the rear surfaces 104b and 103b of the wedge portion 103 adjacent to each other in the moving direction of the belt 100. Torque is transmitted via.

  Further, in a portion where the belt is curved in an arc shape (for example, region B in FIG. 6), the element 102 swings around the locking edge 107 provided on one surface in the stacking direction of the element 102 as a fulcrum. Torque is transmitted by the frictional force between the flank portion 108 (see FIG. 5B) of the element 102 and the pulley.

In the belt 100 wound around the input side pulley 111 and the output side pulley 112, as shown in FIG. 5 (d), between the innermost ring 101a of the belt 100 and the locking edge 107 of the element 102, There is a difference in circumference.
Here, in the pulley on the large diameter side (the pulley on the left side in FIG. 6), the pitch line P (the line connecting the adjacent rocking edges 107) and the innermost ring 101a are provided even though there is a difference in circumference. Since the belt moves at the same angular velocity, slip (relative slip) occurs between the element 102 and the ring 101 at the linear portion of the belt 100 or the portion wound around the input pulley 111 on the small diameter side. Then, this relative sliding becomes a factor of friction and torque transmission efficiency is lowered.

Here, if the height h (the height from the saddle surface 103a to the rocking edge 107) of the contact portion 106 is reduced to reduce the circumferential length difference, the relative slip is reduced, so that transmission efficiency is improved.
However, since the relative sliding between the ring 101 and the element 102 cannot be completely eliminated, the contact portion 106 is likely to be worn out by the amount of the height h of the flat surface 106a of the contact portion 106 being reduced. If this occurs, the transmission efficiency and the durability of the element 102 will be affected.

  Therefore, it is required to reduce the transmission efficiency and suppress the wear of the element.

The present invention is a belt for a continuously variable transmission configured by laminating plate-like elements having slits on both sides and arranging them in an annular shape, and binding each element with an annular ring through which slits are inserted.
The element has an inclined surface whose thickness in the stacking direction decreases as it moves away from the slit on one surface in the stacking direction. The rocking edge, which is the starting position of the inclined surface, is configured to swing around the fulcrum,
On one side of the element, the space between the slit and the rocking edge is a contact portion with the adjacent element in the stacking direction,
The contact portion is formed with a recess that opens to the adjacent element side,
A stepless member is provided in the recess, which is urged in a direction protruding from the recess by the elastic member and protrudes from the recess when the torque transmitted by the belt is less than a predetermined value. Belt for transmission.

According to the present invention, when the torque transmitted by the belt is less than a predetermined value, the protruding member protrudes from the recess and the element swings with the protruding member as a fulcrum, so that the innermost ring and the element swing The difference in circumferential length from the fulcrum of the belt can be reduced, and the relative sliding of the belt can be suppressed. Thereby, transmission efficiency can be improved.
Further, when the transmission torque is greater than or equal to a predetermined value, the torque is transmitted through the entire surface of the contact portion of the element, so that wear of the contact portion can be suppressed.
Thereby, damage to the element can be prevented by suppressing wear of the element.

It is a figure explaining the element in embodiment. It is a figure explaining the principal part of the element in embodiment. It is a figure explaining operation | movement of the element in embodiment. It is a figure explaining the element concerning a modification. It is a figure explaining the belt and element concerning a prior art example. It is a figure explaining the relationship between the belt concerning a prior art example, and the pulley in an automatic transmission.

Embodiments of the present invention will be described below.
1A and 1B are diagrams for explaining an element according to an embodiment, FIG. 1A is a front view of the element 3, FIG. 1B is a cross-sectional view taken along line AA in FIG. FIG. 3 is a side view of the element 3.

  The element 3 in the metal belt of the belt-type continuously variable transmission includes a wedge portion 4 having a saddle surface 40 on which the ring 2 slides and a head portion 5 that forms a slit portion 7 between the saddle surface 40. And a connecting portion 6 that connects the wedge portion 4 and the head portion 5, and the ring 2 is housed in the slit portions 7 on both sides of the connecting portion 6, and is bound to the rings 2 and 2.

  The element 3 comes into contact with pulleys (input-side pulley, output-side pulley) on the flank surface 41 that is the left and right inclined side surfaces of the wedge portion 4, and the friction force between the element 3 and the pulley on the input-side pulley and the output-side pulley Torque is transmitted between them.

  A convex dimple 51 is formed on one surface of the head 5 of the element 3, and a concave hole 52 into which the dimple 51 of the adjacent element 3 is fitted is formed on the other surface. In the following description, the side on which the dimples 51 of the element 3 are provided is the front surface, and the opposite surface is the rear surface.

A tapered surface 4a is provided on the front surface of the wedge portion 4 of the element 3 so that the thickness W in the stacking direction of the elements 3 decreases as the distance from the saddle surface 40 decreases.
The thickness W of the wedge portion 4 in the stacking direction of the elements 3 is thinner below the locking edge 43, which is the starting position of the taper surface 4a, toward the tip (lower end). It has a tapered shape.
Above the locking edge 43 in the wedge portion 4 is a contact portion 42 with the adjacent element 3, and the tapered surface 4 a of the wedge portion 4 is in relation to the front surface 42 a of the contact portion 42 in a sectional view. Is inclined at a predetermined angle.
Here, the locking edge 43 is a boundary line (a boundary line between the front surface 42a of the contact part 42 and the taper surface 4a) where the thickness of the element 3 (wedge part 4) changes.

  FIG. 2A is an enlarged view of a main part of the element 3, and is an enlarged view of a region B in FIG. 2B is a cross-sectional view taken along the line AA in FIG. 2A, and FIG. 2C is a cross-sectional view taken along the line BB in FIG. It is a figure which expands and shows the contact part 42 and its vicinity.

As shown in FIG. 2, in the wedge part 4, the contact part 42 above the locking edge 43 is formed in a range of a predetermined height h from the saddle surface 40. As shown in FIG. The front surface 42 a of the contact portion 42 is flush with the front surface 5 a of the head 5 of the element 3.
In the embodiment, the element 3 is configured such that the front surface 42a of the contact portion 42 is pressed against the back surface 4b of the adjacent element 3 at the linear portion on the compression side of the belt. The element 3 is configured to transmit torque to the adjacent element 3 via the front surface 42 a of the contact portion 42.

As shown in FIG. 2, a housing portion 80 for the protruding member 85 is provided on the front surface 42 a of the contact portion 42.
The accommodating portion 80 is formed on the front surface 42a of the abutting portion 42 along the width direction of the element 3, and has a rectangular shape in a sectional view.
The accommodating portion 80 is formed with a width W1 shorter than the width W2 of the saddle surface 40, and is opened only on the front surface 42a side of the abutting portion 42 (element 3).

  A protruding member 85 and an elastic member 81 are accommodated in the accommodating portion 80. The position of the accommodating portion 80 in the contact portion 42 is a position where the tip end portion 85a of the protruding member 85 is disposed at a position separated from the saddle surface 40 by a predetermined length h1.

In the embodiment, the accommodating portion 80 is provided on the target (one side and the other side of the connecting portion 6) across the center line X (see FIG. 1) of the element 3 in the width direction of the element 3. The protruding members 85 are also provided symmetrically across the center line X (see FIG. 1) on the front surface 42a of the contact portion 42.
In the embodiment, a leaf spring is employed as the elastic member 81, and the protruding member 85 can be moved forward and backward in the axial direction of the accommodating portion 80 (the thickness direction of the contact portion 42) by the elastic member 81. .

  As shown in FIG. 2C, the protruding member 85 has a bullet shape in a cross-sectional view, and the protruding member 85 has a pointed shape in a state where the rear end plane 85 b is supported by the elastic member 81. The front end portion 85a is provided at a reference position protruding from the front surface 42a of the contact portion 42.

Here, at the reference position, the protruding member 85 is provided such that the tip end portion 85a protrudes in a direction away from the front surface 42a with respect to an imaginary line Im passing through the tapered surface 4a.
In the embodiment, while the torque transmitted by the belt is less than a predetermined value and the compressive force acting on the belt element 3 is less than a predetermined pressure, in the curved portion wound around the pulley of the belt, The element 3 swings with the tip end portion 85a of the protruding member 85 as a fulcrum.

When the torque transmitted by the belt is equal to or greater than a predetermined value and the compressive force acting on the element 3 exceeds a predetermined pressure, the protruding member 85 is pushed into the accommodating portion 80 and wound around the pulley of the belt. In the curved portion, the element 3 swings with the locking edge 43 as a fulcrum.
That is, in the curved portion wound around the pulley of the belt in accordance with the compressive force acting on the element 3 (the magnitude of torque transmitted through the belt), the element 3 has a tip 85a of the protruding member 85. And a rocking edge 43 as a fulcrum.

Operation | movement of the belt 1 provided with the element 3 concerning embodiment is demonstrated.
FIG. 3 is a diagram for explaining the operation of the protruding member 85 in the element 3.
(A) of FIG. 3 is a figure explaining the arrangement | sequence of each element 3 in the ring 2 of the belt 1 in case the element 3 rock | fluctuates by using the rocking edge 43 as a fulcrum, (b) is a figure in (a). It is the figure which expanded the part of the protrusion member 85 of the element 3, and was shown typically.
(C) of FIG. 3 is a figure explaining the arrangement | sequence of each element 3 in the belt 1 in case the element 3 rock | fluctuates by the protrusion member 85 as a fulcrum, (d) is a figure of the element 3 in (c). It is the figure which expanded and showed the part of the protrusion member 85 typically.
FIG. 3E is a view for explaining a portion of the belt 1 in which the elements 3 are arranged in a straight line. FIG. 3F is a schematic enlarged view of the protruding member 85 portion of the element 3 in FIG. FIG.

  When the torque transmitted by the belt 1 is large and the compressive force acting on the element 3 is larger than the urging force of the elastic member 81, the protruding member 85 moves toward the housing portion 80 according to the magnitude of the transmitted torque. Will be pushed.

In this state, when the element 3 reaches the curved portion wound around the pulley in the belt 1, the element 3 swings with the locking edge 43 as a fulcrum.
Therefore, in this case, the circumferential length difference between the pitch line P of the element 3 and the innermost ring 2 a of the belt 1 is the same as the height h of the contact portion 42.

  On the other hand, when the torque transmitted by the belt 1 is small and the compressive force acting on the element 3 is smaller than the urging force of the elastic member 81, the projecting member 85 projects from the front surface 42a of the contact portion 42 to the front side. It becomes a state.

In such a state, when the element 3 reaches the curved portion of the belt 1 wound around the pulley, the projecting member 85 projects forward from the extension line (Im in FIG. 2) of the taper surface 4a of the element 3. Therefore, the element 3 swings with the tip end portion 85a of the protruding member 85 as a fulcrum.
Then, the circumferential length difference between the pitch line P of the element 3 and the innermost ring 2a of the belt 1 is the same as the height h1 from the saddle surface 40 to the tip end portion 85a of the protruding member 85.
In this case, since the difference in circumference is smaller than in the case where the element 3 swings around the rocking edge 43 as a fulcrum, the relative slip at the linear portion of the belt 1 or the portion wound around the pulley on the small diameter side is reduced and transmission is performed. Efficiency is improved. Furthermore, since the wear of the contact portion 42 of the element 3 is suppressed by reducing the relative sliding, the durability of the element 3 is improved.

  Since the element 3 is compressed in the laminating direction at the linear portion on the compression side of the belt 1, the protruding member 85 is pushed into the accommodating portion 80, and the front surface 42 a of the abutting portion 42 is located between the adjacent elements 3. It contacts the entire back surface 4b. As a result, torque is transmitted between the elements 3 by using the entire front surface 42a of the contact portion 42.

As described above, the fulcrum when the element 3 swings at the curved portion of the belt changes according to the magnitude of the torque transmitted by the belt, and when the torque transmitted by the belt is smaller than a predetermined value, the projecting member The element oscillates with the tip end 85a of 85 as a fulcrum. When the element is large, the element oscillates with the rocking edge 43 as a fulcrum. Can do. Thereby, since the relative slip of the ring 2a (belt 1) and the element 3 can be suppressed, transmission efficiency can be improved.
Further, in the linear portion on the compression side of the belt, the protruding member 85 is accommodated in the accommodating portion 80, and torque transmission between the elements 3 is performed using the entire front surface 42 a of the abutting portion 42. It will be. At this time, since the contact area of the contact portion 42 can be ensured, the durability of the contact portion 42 (element 3) can be improved.

  Therefore, the height h of the contact portion 42 is set in accordance with the maximum input (maximum torque, maximized transfer, etc.) of the continuously variable transmission, and the durability of the element of the contact portion 42 is improved. When the torque to be transmitted is small, the circumference difference can be reduced to improve the transmission efficiency. Therefore, it is possible to provide a belt that improves fuel efficiency by improving transmission efficiency and improves element (belt) durability.

  In addition, since the protruding member 85 can freely protrude and retract from the accommodating portion 80, when the elements 3 are stacked with the protruding member 85 pushed into the accommodating portion 80 to form a belt, the elements 3 are arranged densely in the belt. Therefore, the gap (end play) between the elements 3 on the non-compressed side of the element in the belt can be prevented from excessively increasing.

As described above, in the embodiment, the plate-like elements 3 having the slit portions 7 on both sides are laminated and arranged in an annular shape, and each of the elements 3 is bound by the annular ring 2 through which the slit portions 7 are inserted. In the belt for a continuously variable transmission configured,
The element 3 includes a taper surface 4a (inclined surface) whose thickness W decreases as the distance from the saddle surface 40 increases on one surface in the stacking direction of the element 3, and the element 3 has a belt on the input side of the continuously variable transmission. Alternatively, when curved in an arc along the output pulley, the rocking edge 43, which is the starting position of the taper surface 4a, is configured to swing around the fulcrum. A front surface 42a of the contact portion 42 between the edge 43 and the edge 3 is a contact portion with the adjacent element 3 in the stacking direction, and the contact portion 42 has a receiving portion 80 that opens to the adjacent element side. A continuously variable transmission that is formed and includes a protruding member 85 that protrudes from the accommodating portion 80 when the torque transmitted by the belt is less than a predetermined value. It was of the belt.

With this configuration, when the torque transmitted by the belt is less than a predetermined value, the element 3 swings with the protruding member 85 protruding from the accommodating portion 80 of the contact portion 42 as a fulcrum.
Thereby, the circumferential difference between the innermost ring 2a and the fulcrum when the element 3 swings can be reduced, and the relative slip between the ring 2a (belt 1) and the element 3 can be suppressed. The transmission efficiency can be improved while suppressing the wear of the contact portion 42 and improving the durability of the element 3.
When the transmission torque is equal to or greater than a predetermined value, the protruding member 85 is accommodated in the accommodating portion 80, and the abutting portion 42 of the element 3 abuts against the back surface of the adjacent element 3 over the entire surface. . Thus, torque is transmitted through the front surface 42a of the contact portion 42 of the element 3, and a pressure receiving area of the contact portion 42 (front surface 42a) that receives a compressive force during torque transmission can be secured. Therefore, since wear of the contact portion 42 can be suppressed, the durability of the element 3 (contact portion 42) is improved.

  Further, the accommodating portion 80 is configured to be formed along the width direction of the element 3 on the front surface 42 a of the abutting portion 42 of the element 3.

  With this configuration, when the element 3 is bent in an arc along the input side or output side pulley of the continuously variable transmission, the compressive force acting on the element 3 is received by the wide projecting member 85. Therefore, since the pressure receiving area in the protrusion member 85 is ensured, durability of the protrusion member 85 can be improved.

  Furthermore, the protruding member 85 is configured to be biased in the direction protruding from the accommodating portion 80 by the elastic member 81 in the accommodating portion 80.

With this configuration, the element 3 swings around the locking edge 43 as a fulcrum by appropriately setting the elastic force of the elastic member 81 according to the magnitude of torque transmitted by the belt type continuously variable transmission. And the case of swinging around the protruding member 85 as a fulcrum can be appropriately switched.
Thereby, when the magnitude of the transmitted torque is small, the circumferential length difference between the fulcrum when the element 3 swings and the innermost belt 2a can be reduced. Relative sliding can be suppressed and transmission efficiency can be improved.
Furthermore, if the relative sliding is suppressed, the wear of the contact portion 42 of the element 3 is suppressed, so that the durability of the element 3 can be improved.

In the above-described embodiment, the case where the protruding member 85 accommodated in the accommodating portion 80 is urged by the elastic member 81 and protruded from the accommodating portion 80 is exemplified.
For example, the protruding member itself may be configured to be elastically deformable.

FIG. 4 is a diagram for explaining a protruding member 90 according to a modification.
The projecting member 90 according to the modified example is formed in an arc shape in which a central portion of the plate-like member is bulged.
The accommodating portion 80A of the abutting portion 42 is formed with protruding portions 421 and 421 that protrude radially inward from both side portions thereof, and the protruding member 90 has protruding portions 421 on both sides 90a in the height direction. 421 is supported.

The projecting member 90 has a central portion 90b in the height direction projecting from the front surface 42a of the contact portion 42 at the reference position, and is held in the accommodating portion 80A in this state.
Both sides 90a of the protruding member 90 are arranged with a space between the side wall 81A of the accommodating portion 80A.

  The projecting member 90 is provided in the accommodating portion 80A so as to be elastically deformable, and when the element including the projecting member 90 receives a predetermined compressive force and abuts on an adjacent element, the projecting member 90 becomes an adjacent element. The back surface 4b is pushed and deformed while being pushed into the accommodating portion 80.

In the embodiment, when the torque transmitted by the belt is less than a predetermined value and the compressive force acting on the element is less than a predetermined pressure, the protruding member 90 is provided so as to protrude from the accommodating portion 80A.
In such a case, the element 3 swings around the central portion 90b of the protruding member 90 in the curved portion wound around the pulley of the belt.
Therefore, even if the projecting member 90 shown in FIG. 4 is used, the circumference difference is smaller than when the element swings around the rocking edge as a fulcrum. As a result, the relative sliding at the portion is reduced, the torque transmission efficiency is improved, and the wear of the contact portion 42 can be suppressed.

DESCRIPTION OF SYMBOLS 1 Belt 2 Ring 2a Ring 3 Element 4 Wedge part 4a Tapered surface 4b Back surface 5 Head 5a Front surface 6 Connection part 7 Slit part (slit)
40 Saddle surface 41 Frank surface 42 Abutting portion 42a Front surface 43 Rocking edge 51 Dimple 52 Hole 80, 80A Housing portion (concave portion)
81 Elastic member 81A Side wall 85 Locking edge substitute member 85a Front end portion 85b Rear end plane 90 Projecting member

Claims (2)

In a belt for a continuously variable transmission configured by laminating plate-like elements having slits on both sides and arranging them annularly, and binding each of the elements with an annular ring through which the slits are inserted,
The element includes, on one surface in the stacking direction, an inclined surface in which the thickness in the stacking direction decreases as the distance from the slit increases.
When the belt is curved in an arc along the pulley on the input side or output side of the continuously variable transmission, the belt is configured to swing around a rocking edge that is a starting position of the inclined surface,
On one surface of the element, the space between the slit and the rocking edge serves as a contact portion with an adjacent element in the stacking direction,
The contact portion is formed with a recess that opens to the adjacent element side,
A protruding member that is urged in a direction protruding from the recess by an elastic member and protrudes from the recess when a torque transmitted by the belt is less than a predetermined value is provided in the recess. Belt for continuously variable transmission.   The belt for a continuously variable transmission according to claim 1, wherein the recess is formed along a width direction of the element.

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