JP3209323B2 - Plate element and belt for belt-type continuously variable transmission, and belt-type continuously variable transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt-type continuously variable transmission used in a power transmission device of an automobile, an industrial machine, or the like to continuously change the speed of rotation from an input shaft and transmit the speed to an output shaft. It is about.

[0002]

2. Description of the Related Art In a power transmission device such as an automobile or an industrial machine, as a transmission for changing the rotation from an input shaft and transmitting the rotation to an output shaft, a gear train step-variable transmission combining gears or a groove width is used. There is a belt-type continuously variable transmission in which a belt is stretched between a pair of pulleys that are variable in the axial direction.

FIG. 5 shows an example of a belt-type continuously variable transmission. This belt-type continuously variable transmission 1 includes a movable pulley disk 2a and a fixed pulley disk 2b and has a movable pulley disk. An input pulley 2 having a variable groove width 2w by moving the input pulley 2a in the direction of the input shaft 3, a movable pulley disk 4a and a fixed pulley disk 4b. between the output side pulley 4 which is variable the groove width 4w by moving in a direction, as shown in FIG. 6, the state sandwiching the ring engaging groove 6 _R of the plate-like element 6 to the two rings 7 In this structure, a large number of belts 8 are provided so as to overlap in the thickness direction.

In such a belt-type continuously variable transmission 1, when the groove width 2w of the input side pulley 2 is large and the groove width 4w of the output side pulley 4 is small, the rotation of the input shaft 3 is reduced (automobile). Is transmitted to the output shaft 5 in a low state, and the groove width 2w of the input side pulley 2
Is small and the groove width 4w of the output side pulley 4 is large, the rotation of the input shaft 3 is transmitted to the output shaft 5 in a state where the rotation of the input shaft 3 is accelerated (in a case of an automobile, in an overdrive state).

[0005] As a belt type continuously variable transmission having such a structure, there is one described in "C3 Automatic Transaxle" issued in January 1992, "NISSAN March", a new vehicle manual.

[0006] Such a belt-type continuously variable transmission 1
In the wall surface of the pulley 2 and 4, it is necessary that sufficient frictional forces between the elements side surface 6 _F is the contact surface with the wall surface of the pulley 2, 4 of the plate-like element 6 occurs, also, It is necessary to prevent the lubricant film formed on the contact surface from slipping due to the oil film.

Therefore, for example, the lubricating oil is sufficiently released from the contact surface to prevent slipping and to ensure a sufficient frictional force. Groove has a total area of 7 in _F
There has also been developed a technique in which projections and grooves occupying 5 to 90% are alternately provided in a direction that matches or approximates the thickness direction (for example, Japanese Patent Application Laid-Open No. 2-236045).

[0008]

In the technique described above, the projections and the grooves are alternately provided on the element side surfaces of the plate-like element in a direction matching or approximating the plate thickness direction.
By regulating the ratio and depth of the groove, the lubricant is quickly released and the wear on the side of the element is suppressed, but according to the analysis results of the present inventors, The part where the wall surface of the pulley and the element side surface of the plate-like element are in actual metal contact is only a very small area of the surface of the protrusion provided on the side surface of the element, and the surface roughness of the surface of this protrusion is It has been confirmed that when the roughness is somewhat coarse, a larger friction coefficient can be obtained and a larger transmission torque can be obtained.

Therefore, it was an object to develop a plate-type element for a belt-type continuously variable transmission having an element side surface that meets such analysis results.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to solve such a problem, and a belt type having a larger coefficient of friction, a larger transmission torque, and less wear. It is an object to provide a plate-like element for a continuously variable transmission.

[0011]

According to the present invention, there is provided a belt-type continuously variable transmission plate-like element according to the present invention, comprising an input pulley having a groove width variable in an input shaft direction. In a belt-type continuously variable transmission in which a number of plate-shaped elements are stacked in the thickness direction between the output pulley and a groove width that is variable in the output shaft direction and a belt is provided, On the side of the element, which is the contact surface with the wall surface of the pulley, projections and grooves are alternately provided in the direction parallel to or parallel to the plate thickness direction (parallel or inclined direction to the plate thickness direction), and the projections contact the pulley wall surface. The surface is made uneven, and the center line average roughness in the state of the uneven shape is Ra 0.2 μm or more and 1.1 μm or less.

[0012]

[0013] In the embodiment of the plate-shaped element for a belt-type continuously variable transmission according to the present invention, as described in claim 2, the projection surface has a random irregular shape. And specifically, for example,
As described in claim 3, the surface of the projection may be a shot blast surface.

Similarly, in the embodiment of the plate-like element for a belt-type continuously variable transmission according to the present invention, as described in claim 4, the surface of the protrusion is in a direction that is coincident with or approximates the thickness direction. The projections and the depressions may be in the form of an alternating concavo-convex shape. Specifically, for example, as described in claim 5, the projection surface is a ground surface. can do.

In the belt for a belt-type continuously variable transmission according to the present invention, the plate-like element according to any one of claims 1 to 5 is provided on a ring in the thickness direction. , And a large number of them are provided.

Further, according to a seventh aspect of the present invention, there is provided a belt-type continuously variable transmission, wherein an input-side pulley having a variable groove width in an input shaft direction and a groove width in an output shaft direction. The belt according to claim 6 is stretched between the output pulley and the output pulley.

The plate-shaped element for a belt-type continuously variable transmission according to the present invention has the above-mentioned configuration, and the plate-shaped element is made of carbon steel for machine structure, alloy steel for machine structure, carbon tool steel, An alloy tool steel or the like that has been subjected to carburizing treatment, carbonitriding treatment, induction heat treatment, quenching and tempering treatment, or the like is used.

In this case, it is desirable that the tempering be performed by low-temperature tempering to give a sufficient hardness, thereby reducing the wear.

Further, on the element side surface of the plate-like element, projections and grooves are alternately provided in a direction which is coincident with or approximate to the plate thickness direction (parallel or inclined direction), and the surface of the projection has an uneven shape. However, in this case, if the center line average roughness in the state of the concavo-convex shape is smaller than Ra0.2 μm, it becomes difficult to obtain a sufficient friction coefficient, and thus it is possible to obtain a large transmission torque. Therefore, the thickness is set to 0.2 μm or more.

On the other hand, if the center line average roughness in a state where the surface of the projection is uneven is larger than Ra1.1 μm, a sufficient friction coefficient can be obtained, but the wear of the projection surface and the pulley wall surface is reduced. Tend to increase.
1 μm or less.

When the surface of the projection is made uneven, for example, shot blasting such as spraying sand or steel shot can be performed, and the surface of the projection has a random uneven shape. It can be composed of a shot blast surface.

Similarly, when the surface of the projection is made uneven, grinding can be performed, for example, so that the projection and the depression are alternately formed in a direction in which the surface of the projection matches or approximates the thickness direction. It can be made of a ground surface to be formed.

[0023]

According to the plate-like element for a belt-type continuously variable transmission of the present invention, an input pulley having a variable groove width in the input shaft direction and an output pulley having a variable groove width in the output shaft direction. In a belt-type continuously variable transmission in which a large number of plate-like elements are stacked in the thickness direction thereof and a belt is provided, a plate-like element is provided on a side surface of the element which is a contact surface with a pulley wall surface. Protrusions and grooves in the direction that matches or approximates the thickness direction are alternately provided, and the surface of the protrusion that comes into contact with the pulley wall surface is made uneven, so that it has a larger coefficient of friction and, therefore, a larger transmission torque. And an extremely excellent effect that a plate-shaped element for a belt-type continuously variable transmission with less wear can be obtained. By setting the center line average roughness in the shape of the shape to be Ra 0.2 μm or more and 1.1 μm or less, it is possible to obtain a sufficient friction coefficient and wear when the surface roughness becomes excessive. A remarkably excellent effect is obtained that an increase in the depth can be prevented.

[0024]

According to the second aspect of the present invention, the surface of the projection has a random irregular shape, so that the belt type continuously variable transmission has a large friction coefficient and a large transmission torque. It is possible to use a plate-shaped element. In this case, as described in claim 3, the projection surface is a shot blast surface, so that a random uneven shape is shot blasted. Thus, a remarkably excellent effect of being able to be mass-produced is obtained.

Still further, as described in claim 4, the surface of the projection has an uneven shape in which projections and recesses in the direction that matches or approximates the thickness direction alternate. A plate-shaped element for a belt-type continuously variable transmission that has a large coefficient of friction and a large transmission torque because it can further improve the coefficient of friction and wear as compared with those having a random uneven shape. In this case, the belt surface is more stable and has a larger coefficient of friction by making the protrusion surface a ground surface as described in claim 5. A remarkably excellent effect that a plate-shaped element for a continuously variable transmission can be obtained is obtained.

The belt for a belt-type continuously variable transmission according to the present invention has a structure in which a plurality of plate-shaped elements according to any one of claims 1 to 5 are provided on a ring in the thickness direction of the belt. A remarkably excellent effect is obtained in that it can be used as a component of a belt-type continuously variable transmission that has excellent transmission characteristics and can obtain a larger transmission torque.

The belt-type continuously variable transmission according to the present invention is characterized in that between the input pulley having a variable groove width in the input shaft direction and the output pulley having a variable groove width in the output shaft direction. 6, the belt-type continuously variable transmission having excellent torque transmission characteristics and a large transmission torque can be provided.

[0029]

FIG. 1 shows an embodiment of a plate-shaped element for a belt-type continuously variable transmission according to the present invention. This plate-shaped element 6 for a belt-type continuously variable transmission is shown in FIG. together and a ring engaging groove 6 _R for fitting the ring 7, the element side 6 _F is the contact surface with the wall surface of the input side pulley 2 and the output-side pulley 4 shown in FIG. 5
have.

[0030] Then, the element side surface 6 _F of the plate-like element 6, as shown enlarged in FIG. 2, projections 6 _FP direction (direction parallel or inclined) that matches or approximates the thickness T direction and with is provided with a groove _{6 FR} alternately, in the projection _{6 FP,} as shown in FIG. 3 and FIG. 4
As shown in, and an uneven shape projection surface 6 _P in contact with the pulley walls.

The sand upon these, FIG. 3, the uneven shape of projection surface 6 _P in contact with the pulley wall, shows the case of the as a random uneven shape, as a shot material in this embodiment This shows a case where an uneven shape composed of a shot blast surface is provided by shot blasting (sand blasting).

Further, FIG. 4, when the projection surface 6 _P that contacts the pulley walls and uneven shape, protrusions 6 _PP and the recess in the direction (direction parallel or inclined) to match or approximate to the thickness T direction 6 shows a case in which the _PR has an alternately uneven shape, and this embodiment shows a case in which the unevenness formed by the ground surface is provided by grinding.

The plate element 6 in this embodiment is
Carbon tool steel (SK1) is a material, which has a ring engaging groove 6 _R as shown in FIG. 1, protrusions 6 _FP and the groove portions in the thickness direction and the direction parallel to the element side face 6 _F as shown in FIG. 2 6 _FR perform punching into a shape is formed, and subjected to subsequent quenching and low temperature tempering treatment.

In the first embodiment, the element side surface 6
The surface _{6 P} of _F projections _{6 FP} is polished by using sand blasting, center line average surface roughness Ra0.82μ
A plate-like element 6 having m irregularly fine irregularities was produced.

In the second embodiment, the element side surface _6F
By grinding the surface _{6 P} of the projections _{6 FP} in the thickness direction and parallel, a center line average surface roughness Ra0.23μm
The projection _6PP and the depression _6PR are formed to produce a plate-like element 6 having an uneven shape.

Further, in Examples 3 to 6, the center line average surface roughness Ra was 0.45 μm in Example 3, and the center line average surface roughness Ra1 was obtained in Example 4 by changing the grinding conditions used in Example 2. .02Myuemu, example 5, the center line average surface roughness Ra0.14Myuemu, protrusions _{6 PP} and recesses of example 6, the center line average surface roughness Ra1.55Myuemu 6
A plate-like element 6 having _PR formed thereon and having an uneven shape was produced.

Further, in the seventh embodiment, as in the first embodiment, the surface 6 _P of the projection 6 _FP is sandblasted to form a randomly fine unevenness having a center line average surface roughness Ra of 0.18 μm. The plate element 6 was prepared.

Next, each of the plate-like elements 6 manufactured as described above is slid in the plate thickness direction and fixed with a jig, and then carburized steel (SCM4) is used as a substitute for the wall surface of the pulley.
25) The flat plate specimen is rotated and slid in lubricating oil for an automatic transmission by using the flat plate specimen of 25) to obtain a coefficient of friction between the plate-like element 6 and the flat plate specimen, the element side surface _6F and the flat plate. The wear amount of the test piece surface was measured.

Here, the coefficient of friction is determined by measuring the amount of strain of a strain gauge on an arm attached to a jig to which the plate element 6 is fixed, and dividing the frictional force converted therefrom by the applied load. I asked.

Table 1 summarizes the test conditions at this time.
Table 2 summarizes the results of these tests.

[0041]

[Table 1]

[0042]

[Table 2]

[0043] In Table 2 results shown from as will be apparent to, Example 7 element side 6 _F are Examples 5 and element side surfaces 6 _F a grinding surface is blasted surface,
Since the center line average surface roughness of the projections 6 _FP is small and less than Ra of 0.2 m, coefficient of friction generated becomes as hard to obtain as small as 0.06 or less, a large transmission torque.

On the other hand, in Example 6 element side _{6 F} is the grinding surface, the center line average surface roughness of the projections _{6 FP} Ra
Since it exceeds 1.1 μm, although the coefficient of friction is large, the amount of wear of the projection _6FP and the mating material is large.

On the other hand, in Example 2-4 Example element side _{6 F} is blasted surfaces 1 and element side surfaces _{6 F} is the grinding surface, the center line average surface roughness of the projections _{6 FP Ra0.2~} Since the diameter is within the range of 1.1 μm, a large friction coefficient can be obtained and the protrusion 6
The wear of the _FP and the mating material was also small.

[0046] and, in particular, as compared with the case of Example 1 which is a random uneven shape, exemplary projecting portion 6 _PP and the recess 6 _PR in the thickness direction and parallel direction are an uneven shape forming the alternating example In the cases of 2 to 4, it was recognized that the effect of improvement on the coefficient of friction and wear was greater.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a slope showing an embodiment of a plate element for a belt-type continuously variable transmission according to the present invention.

FIG. 2 is an explanatory view illustrating an enlarged side view of an element side surface of the plate-shaped element for a belt-type continuously variable transmission shown in FIG. 1;

FIG. 3 is an explanatory view of a slope of a projection in which the surface of the projection on the side surface of the element shown in FIG. 2 has a random uneven shape.

FIG. 4 is an explanatory view of a slope of a projection in which the surface of the projection on the side surface of the element shown in FIG. 2 has an irregular shape in which projections and recesses in the direction parallel to the thickness direction are alternately formed.

FIG. 5 is an explanatory sectional view showing a basic configuration of a belt-type continuously variable transmission.

6 is an explanatory view of a slope (FIG. 6 (a)) of a belt constituting the belt-type continuously variable transmission shown in FIG. 5 and an explanatory view of a slope of a plate-like element (FIG. 6 (b)).

[Description of Signs] 1 Belt type continuously variable transmission 2 Input side pulley 2a Movable side pulley board of input side pulley 2b Fixed side pulley board of input side pulley 2w Groove width of input side pulley 3 Input shaft 4 Output side pulley 4a Output Movable pulley board of side pulley 4b Fixed pulley board of output side pulley 4w Groove width of output side pulley 5 Output shaft 6 Plate element 6 _F element side 6 _FP element side protrusion 6 _FR element side groove 6 _P protrusion Part surface 6 Convex part on _PP protruding part surface 6 Concave part on _PR protruding part surface 7 Ring 8 Belt

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akio Sano Nissan Motor Co., Ltd., 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture (56) References JP-A-2-236045 (JP, A) JP-A-Hei 5-157146 (JP, A) Japanese Utility Model 63-175333 (JP, U) Japanese Utility Model 58-97337 (JP, U) Japanese Utility Model 62-840 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F16G 5/16

Claims (7)

(57) [Claims] 1. A large number of plate-like elements are stacked in the thickness direction between an input pulley having a variable groove width in an input axis direction and an output pulley having a variable groove width in an output axis direction. In a belt-type continuously variable transmission in which a belt is provided, a protrusion and a groove are provided alternately on a side surface of the plate-like element, which is a contact surface with a pulley wall surface, in a direction that matches or approximates a plate thickness direction. A belt-type continuously variable transmission, characterized in that the surface of the projection in contact with the wall surface of the pulley has an uneven shape, and the center line average roughness in the state of the uneven shape is Ra 0.2 μm or more and 1.1 μm or less. Plate element. 2. The plate element for a belt-type continuously variable transmission according to claim 1, wherein the surface of the projection has a random uneven shape. 3. The plate-shaped element for a belt-type continuously variable transmission according to claim 2, wherein the surface of the projection is a shot blast surface. 4. The plate-shaped element for a belt-type continuously variable transmission according to claim 1, wherein the surface of the protrusion has an uneven shape in which a protrusion and a recess in a direction that matches or approximates the thickness direction alternate. 5. The surface of the projection is a ground surface.
3. The plate-shaped element for a belt-type continuously variable transmission according to claim 1. 6. A belt for a belt-type continuously variable transmission, wherein a number of the plate-shaped elements according to claim 1 are provided on a ring in a thickness direction. 7. The belt according to claim 6, which is hung between an input pulley having a variable groove width in the input axis direction and an output pulley having a variable groove width in the output axis direction. A belt-type continuously variable transmission characterized by the following.