CN1238425A - Belt guiding device of belt-type buncher - Google Patents

Abstract

The present invention provides a belt guide device for a belt-type continuously variable transmission. A guide roller 33 is provided between the driving pulley 4 and the driven pulley 21. The gap between the outer peripheral surface of the guide roller 33 and the inner peripheral surface of the belt 13 is in the transmission The high-speed range is large, and the low-speed range is small. Therefore, when the belt vibrates abnormally, the vibration of the belt can be suppressed, the impact sound of the belt can be reduced, and at the same time, the abrasion of the belt can be reduced and the service life can be improved.

Description

Belt guides for belt-type continuously variable transmissions

The present invention relates to the belt guide device of the belt-type continuously variable transmission used in the power plant of motor two-wheel and tricycle etc., especially relates to such a kind of belt guide device of such a new type belt-type continuously variable transmission, it can suppress the winding as far as possible The abnormal vibration of the endless belt between the drive pulley and the driven pulley reduces belt rattling and improves the life of the belt.

As the belt guide device of the belt-type continuously variable transmission, there is, for example, the device described in Japanese Patent Application Laid-Open No. 3-39650.

This belt-type continuously variable transmission has a variable-diameter driving pulley provided on the crankshaft of the engine, a variable-diameter driven pulley provided on the transmission input shaft connected to the driving wheels, and a pulley wound between the two pulleys. For an endless belt, a guide roller that can contact the inner peripheral surface of the belt is provided between the two pulleys, and a gap is formed between the guide roller and the inner peripheral surface of the belt. When the belt vibrates abnormally, the inner peripheral surface of the belt contacts the guide The outer peripheral surface of the roller, thereby suppressing the abnormal vibration of the belt.

In general, in the above-mentioned belt-type continuously variable transmission, by adjusting the effective diameter of the driving pulleys, by changing the contact effective pitch circle diameter between these pulleys and the belt, the transmission ratio can be changed from a low ratio area (including idle speed to a high speed change Ratio area) is steplessly adjusted to the high ratio area (low gear ratio area). In the entire range from the above-mentioned low ratio to the high ratio, the knocking sound is not generated by the vibration of the belt at the same level. In the low ratio In the high ratio region, the vibration of the belt becomes relatively larger, and the harsh belt slamming sound becomes louder. Conversely, in the high ratio region, the belt vibration becomes smaller, and the above-mentioned belt slapping sound also becomes smaller.

However, in the belt guide device of the above-mentioned existing belt-type continuously variable transmission, the gap between the belt and the guide pulley is all substantially the same from the low ratio region to the high ratio region, so even if the belt bumping sound is small and the driver is not very In the high proportion area of interest, the belt also contacts the guide rollers in the same way. Of course, this has the problem of wearing the belt and making it difficult to improve its life.

Therefore, the object of the present invention is to provide a novel belt-type continuously variable transmission belt guide. The driven pulley moves in parallel, so that the contact state between the belt and the guide member can be changed in the above-mentioned low-ratio area and high-ratio area, thereby reducing the abnormality of the belt, that is, the belt knocking sound caused by the ups and downs, and suppressing the wear of the belt at the same time. increase its lifespan.

In order to achieve the above object, according to the first item of the present invention, the belt-type continuously variable transmission consists of a variable-diameter driving pulley connected to the driving side, a variable-diameter driven pulley connected to the driven side, and a belt-type continuously variable transmission. The ring-shaped belt between the two pulleys is formed, and the transmission ratio can be changed by variable control of the winding diameter of the above two pulleys and the belt; it is characterized in that: when the belt is abnormally vibrating, it is set between the driving pulley and the driven pulley. A guide member that can be in contact with the peripheral surface of the belt during operation, and a gap is provided between the belt guide surface of the guide member and the peripheral surface of the belt facing the belt guide surface. Larger when the belt is in the low gear ratio range. According to this feature, when the belt vibrates abnormally, the belt can be guided by the guide member to reduce the belt bumping sound, avoid unnecessary contact between the belt and the guide member, and improve the life of the belt.

In order to achieve the above-mentioned purpose, according to the second solution of the present invention, in the above-mentioned first solution, it also has such a feature: the belt guide surface of the above-mentioned guide member has a first guide portion and a In the second guide portion facing the belt in the low speed ratio region, the gap between the first guide portion and the belt peripheral surface is small, and the gap between the second guide portion and the belt peripheral surface is large, and the strength of the first guide portion is higher than that of the belt. The 2nd guide is low. According to this feature, in addition to the above-mentioned effects, the belt can be brought into contact with the guide member in a cushioned manner, thereby further reducing the rattling sound of the belt.

In order to achieve the above object, according to the third aspect of the present invention, in the second aspect, the above-mentioned first guide part is further to one side than the center of gravity of the belt cross section when the belt is in the high speed ratio region. According to this feature, in addition to the above-mentioned effects, the belt can be inclined to contact the guide member in a stepped manner, thereby further reducing the sound of the belt rattling.

In order to achieve the above object, according to the fourth solution of the present invention, in the above-mentioned first, second or third solutions, it also has such a feature: the above-mentioned guide member is composed of a guide roller, which can be freely rotatably arranged on the above-mentioned drive pulley and from the In the middle of the moving pulley, there is a belt guide surface facing the inner peripheral surface of the above-mentioned belt on its outer peripheral surface. 2nd guide part made of surface. According to this feature, in addition to the above effects, when the belt comes into contact with the guide roller, the guide roller rotates, so that the wear of the belt and the guide roller can be further reduced.

In order to achieve the above object, according to the fifth aspect of the present invention, it is characterized in that the above-mentioned guide member is integrally protruded from the case body surrounding the above-mentioned belt-type continuously variable transmission, and the belt guide facing the peripheral surface of the belt The surface is formed with the above-mentioned first guide part constituted by the high-level surface and the second guide part constituted by the low-level surface, and the gap between the first guide part and the belt peripheral surface is smaller than the gap between the second guide part and the belt peripheral surface. According to this feature, on the basis of the above effects, the guide member for guiding the belt is composed of upper and lower fixed guide pieces integrally protruding from the box body, which can reduce the number of parts and assembly time, and greatly reduce the cost.

A brief description of the accompanying drawings is as follows:

Fig. 1 is a sectional view taken along line 1-1 in Fig. 2 of a power unit provided with a belt guide of a belt-type continuously variable transmission (first embodiment).

Fig. 2 is a cross-sectional view of the above-mentioned power plant along line 2-2 in Fig. 1 (first embodiment).

Fig. 3 is a side view of the belt guide (first embodiment).

Fig. 4 is a longitudinal sectional view of the belt guide device along line 4-4 in Fig. 3 (first embodiment).

Fig. 5 is a side view of main parts of a belt guide device of a belt-type continuously variable transmission (second embodiment).

Fig. 6 is a sectional view along line 6-6 in Fig. 5 (second embodiment).

Fig. 7 is a side view of main parts of a belt guide device of a belt-type continuously variable transmission (third embodiment).

Fig. 8 is a sectional view along line 8-8 in Fig. 7 (third embodiment).

Fig. 9 is a side view of main parts of a belt guide device of a belt-type continuously variable transmission (fourth embodiment).

Fig. 10 is a sectional view taken along line 10-10 in Fig. 9 (fourth embodiment).

Fig. 11 is a side view of main parts of a belt guide device of a belt-type continuously variable transmission (fifth embodiment).

Fig. 12 is a sectional view along line 12-12 in Fig. 11 (fifth embodiment).

Next, embodiments of the present invention will be described based on the embodiments of the present invention shown in the drawings. In the following description, "front and rear", "left and right", and "up and down" are judged based on the forward direction of the motorcycle.

First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. The first embodiment is a case where the belt guide device of the belt type continuously variable transmission of the present invention is implemented in a swing type power plant for a motorcycle.

Fig. 1 is a sectional view along line 1-1 in Fig. 2 of a power unit provided with a belt guide device of a belt-type continuously variable transmission of the present invention, and Fig. 2 is a cross-sectional view of the above-mentioned power unit along line 2-2 in Fig. 1 , Figure 3 is a side view of the belt guide, and Figure 4 is a longitudinal sectional view of the belt guide along the line 4-4 in Figure 3.

In Figs. 1 and 2, the swing power unit P equipped with the above-mentioned belt-type continuously variable transmission is supported on the body F of the motorcycle so that the front part can swing up and down through the swing shaft S, and the rear part passes through the rear buffer Cr. Suspended on frame F.

The above-mentioned power unit P is composed of an engine E, a rear wheel Wr, a belt-type continuously variable transmission B and a gear reducer G which are linked together. The driving force of the engine E is transmitted to the rear wheel.

The case body 1 of the above-mentioned power unit P is formed long in the front-rear direction in order to connect the above-mentioned engine E and the rear wheel Wr, and its front part also serves as a part of the crankcase 2 of the engine E, and the front part of the case body 1 forms the crankshaft of the engine E. Left half of box 2. A crankshaft 3 of the engine E is rotatably supported by a pair of ball bearings 14 and 15 in a crankcase 2 thereof. A variable-diameter drive pulley 4 is provided at the left end of the above-mentioned crankshaft 3 extending to the side of the box body 1, and the drive pulley 4 is composed of a fixed pulley half 5 and a movable pulley half 6 that can advance and retreat relative thereto. Between the inclined plate 7 fixed to the crankshaft 3 so as not to be able to rotate relative to it and the fixed-side pulley half body 5, a spacer ring 8 fitted to the crankshaft 3 is installed, and the above-mentioned movable pulley is slidably supported on the spacer ring 8. half body6. The slider 9 provided on the outer peripheral portion of the inclined plate 7 is slidably engaged with the guide piece 10 formed in the axial direction of the movable side pulley half body 6, so that the inclined plate 7 allows the movement of the movable side pulley half body 6. While sliding in the axial direction, it can rotate integrally with the movable side pulley half body 6 . A space 11 having a tapered surface narrowed radially outward is formed between the inclined back surface of the movable side pulley half body 6 and the inclined plate 7, and a centrifugal weight 12 composed of rollers is accommodated in the space 11. When the rotation speed of the crankshaft 3 increases and the centrifugal force of the centrifugal weight 12 increases, the centrifugal weight 12 moves radially outward in the space 11 with a tapered surface, and pushes the movable side pulley half body 6. The distance between the moving pulley half body 6 moving to the left and the fixed side pulley half body 5 is reduced, so that the V-shaped endless belt 13 clamped between the two pulley half bodies 5 and 6 is parallel to the radially outer side. Move, so that the effective pitch diameter of the belt 13 for the drive pulley 4 can be adjusted.

On the other hand, the housing 16 of the gear reducer G is fixed to the rear of the box body 1, and the gear reducer is freely rotatably supported by ball bearings 17 and 18 between the rear of the box body 1 and the housing 16. The input shaft 20 of the speed reducer of G supports a variable-diameter driven pulley 21 composed of a fixed-side pulley half 22 and a movable-side pulley half 23 on the input shaft 20, and is wound around the driven pulley 21. The aforementioned endless belt 13 . The fixed-side pulley half 22 is axially slidably supported on the speed reducer input shaft 20 , and is elastically biased by a spring 24 in a direction toward the fixed-side pulley half 22 .

A forward clutch 25 is attached to the left end of the reducer input shaft 20, and a driving gear 26 of the above-mentioned gear reducer G is formed at the right end thereof. The above-mentioned gear reducer G is arranged in the housing 16 fixed to the right side of the rear part of the box body 1 by a plurality of bolts, and the above-mentioned drive gear 26 is connected to the driven gear fixed to the axle 28 of the rear wheel Wr through a known reduction gear mechanism 27 and 29 interlocking, the rotation of the reducer input shaft 20 can be decelerated and transmitted to the rear wheel Wr.

The open side of the above-mentioned box body 1 is covered by an outer cover 31, and the outer cover 31 is fixed here by a plurality of bolts, and the belt-type continuously variable transmission B composed of the above-mentioned driving pulley 4, driven pulley 21 and endless belt 13 is housed in it. Inside the transmission accommodating space 32 surrounded by the above-mentioned case body 1 and the outer cover 31 .

A guide roller 33 as a guide member for suppressing abnormal vibration of the belt 13 is attached to the center between the driving pulley 4 and the driven pulley 21 in the transmission housing space 32 . As shown in FIGS. 1 and 2 , the guide roller 33 is arranged at a substantially central portion of the crankshaft 3 supporting the drive pulley 4 and the reducer input shaft 20 supporting the driven pulley 21 . Therefore, even if the gear ratio of the belt-type continuously variable transmission B changes and the line of the belt 13 changes from a low-ratio range to a high-ratio range as shown in FIG. must. As long as the belt 13 does not vibrate abnormally, the diameter of the guide roller 33 can maintain a predetermined gap between the outer peripheral surface of the guide roller 33 , that is, the belt contact surface, and the inner peripheral surface of the belt 13 .

As shown in FIG. 4, the above-mentioned guide roller 33 is freely rotatably supported on a stepped bolt 36 through a ball bearing 37, and the bolt 36 is fixed to a boss protruding from the inner peripheral surface of the box body 1 toward the outer cover 31 side. Taiwan 35.

As shown in FIGS. 3 and 4 , the guide roller 33 is formed by sintering and bonding an outer member 39 made of an elastic material such as rubber to the outer periphery of an inner member 38 made of metal such as Fe or Al, and a concave portion is formed on the inner surface of the inner member 38. 40 and a lubricating box 41, the outer race of the above-mentioned ball bearing 37 is fixed in cooperation with the recess 40, and the lubricating box 41 is used to prevent the grease adhering to the ball bearing 37 from flowing out into the inside of the box body 1 and adhering to the belt 13. A belt guide surface 43 is formed on the outer peripheral surface of the outer member 39 of the guide roller 33 . The axial width of the belt guide surface 43 is equal to or slightly larger than the moving width of the inner peripheral surface of the belt 13 when the belt 13 moves from the low ratio area to the high ratio area in parallel to the left and right. The guide roller 33 has annular grooves 44, 45 on both sides of the outer member 39 made of rubber, and its outer peripheral portion 46 is formed in an annular shape. The first guide portion 43 ₁ constituted by a large-diameter protruding portion protruding outward in the radial direction forms a second guide portion 43 ₂ with a flat surface in the remaining portion except the first guide portion 43 ₁ . The second guide portion ₄₃₂ occupies most of the above-mentioned belt guide surface 43, and the flat second guide portion ₄₃₂ is smoothly connected to the radially outwardly protruding inclined surface by the continuous upward inclined surface. The first guide portion 43 ₁ constituted by a large-diameter protrusion. The radial thickness of the first guide portion ₄₃₁ constituted by a large-diameter protrusion protruding outward in the radial direction is thinner than that of the second guide portion ₄₃₂ , and is relatively weak and flexible. As shown by the solid line in Fig. 4, when the belt-type continuously variable transmission B is in the low-ratio region, the inner peripheral surface of the belt 13 moves toward the first guide formed by the large-diameter protrusion protruding radially outward. 43 ₁ , and as shown by the two-dot chain line in FIG. 4 , when the belt 13 is in the high ratio region, the inner peripheral surface of the belt 13 faces the second guide portion 43 ₂ .

A cylindrical labyrinth rib 48 protrudes from the outer periphery of the above-mentioned boss portion of the box body 1, which constitutes a labyrinth packing, and the labyrinth packing is used to work together with the lubrication box 41 of the above-mentioned guide roller 33 to prevent Grease flows out from the ball bearing 37 to the transmission housing space 32 .

Next, the operation of the first embodiment of the present invention having the above-mentioned structure will be described.

When the crankshaft 3 is rotated by the operation of the engine E, the rotation is transmitted to the reducer input shaft 20 through the above-mentioned belt type continuously variable transmission B, and then transmitted to the rear wheel Wr through the gear reducer G, so that the motorcycle can run.

However, when the rotation of the engine E gradually increases, the centrifugal weight 12 moves radially outward under the centrifugal force, so that the movable side pulley half 6 of the drive pulley 4 of the belt-type continuously variable transmission B moves towards a fixed position. The direction of side pulley half body 5 moves. As the two pulley halves 5 , 6 approach, the width of the V space formed therebetween becomes smaller, and the belt 13 moves radially outward of the drive pulley 4 . When the belt 13 moves to the outside, the movable pulley half body 23 on the side of the driven pulley 21 is pushed by the belt 13 and moves to the left while resisting the elastic force of the spring 24, and is formed on the two pulley half bodies 22, 23. The width of the V space therebetween becomes larger, and the belt 13 moves in parallel toward the radially inner side of the driven pulley half body 21 . In this way, the engine E is continuously variable, and is in a low-ratio region with a large transmission ratio when rotating at a low speed, and is in a high-ratio region with a small transmission ratio when rotating at a high speed. When running a motorcycle, the belt-type continuously variable transmission B is naturally used more frequently in the high-ratio area than in the low-ratio area because it travels more in the high-ratio area.

During normal operation of the power plant P, the endless belt 13 is stretched linearly between the driving pulley 4 and the driven pulley 21, and between the inner peripheral surface of the belt 13 and the belt guide surface 43 of the guide roller 33. Form a specified gap. In this way, unnecessary contact of the belt 13 with the guide roller 33 can be avoided, so that the life of the belt 13 will not be reduced due to the frictional heat generated by the contact.

The vibration of the driving pulley 4 and the driven pulley 21, the change of the lateral pressure between them and the belt 13, the change of the frictional force of the belt 13, the torque fluctuation of the engine E, etc. will cause abnormal vibration in the belt 13, but in this case The inner peripheral surface of the belt 13 is in contact with the outer peripheral surface of the guide roller 33, that is, the belt guide surface 43, which can effectively suppress its vibration and reduce the generation of the impact sound caused by the contact of the belt 13 on the box body 1, especially in the first embodiment. In this example, changing the contact state between the inner peripheral surface of the belt 13 and the belt guide surface 43 of the guide roller 33 corresponding to the working state of the belt-type continuously variable transmission B can reduce the occurrence of the above-mentioned impact sound as much as possible, and greatly Greatly improve the life of the belt 13. The following describes its working status in detail.

(1) When the belt-type continuously variable transmission B works in a low-ratio area with a large transmission ratio

At this time, as shown in FIG. 4, the belt 13 moves in parallel to the box body 1 side, that is, the solid line position on the right side of FIGS. The inner peripheral surface of the belt 13 faces the first guide portion ₄₃₁ of the guide roller 33 which is formed of a large-diameter protrusion. Thus, the gap between the inner peripheral surface of the belt 13 and the belt guide surface 43 of the guide roller 33 becomes small. When the belt 13 vibrates abnormally, the belt 13 eliminates the above-mentioned narrow gap d ₁ , and its inner peripheral surface contacts the first guide portion 43 1 or the first guide portion 43 ₁ formed by a large-diameter protrusion on the guide roller 33 obliquely in the form of a step. 1.2 The guides 43 ₁ , 43 ₂ have a small contact area and can be in uneven contact. In addition, the above-mentioned first guide 43 ₁ is formed softly with low strength, so it can contact the belt 13 with cushioning. The comprehensive effect can effectively reduce the belt bumping noise caused by the contact of the belt 13 with the guide roller 33 .

As described above, when the belt-type continuously variable transmission B operates in the low-ratio range, it is possible to reduce as much as possible the above-mentioned harsh belt knocking sound, which is easily perceived by the user, generated by the vibration of the belt 13 .

(2) When the belt-type continuously variable transmission B works in a high-ratio area with a small transmission ratio

Now, the belt 13 moves in parallel to the side away from the box body 1 side, that is, the left side of Fig. The constituted second guide portion ₄₃₂ is opposite to each other. Thus, the gap between the inner peripheral surface of the belt 13 and the belt guide surface 43 of the guide roller 33 becomes larger than in the case of the above-mentioned low ratio region. When the belt 13 vibrates abnormally, the frequency of contact between its inner peripheral surface and the belt guide surface 43 of the guide roller 33 is greatly reduced compared with the situation in the above-mentioned low ratio area, and the inner peripheral surface of the belt 13 and the Since the flat second guide portion ₄₃₂ of the guide roller 33 is in contact with each other, the contact area thereof is larger than in the case of the above-mentioned low ratio region.

For the belt 13 of the belt-type continuously variable transmission B, its action is more stable in its high-ratio region than in its low-ratio region, and the abnormal vibration is small. Therefore, by reducing the contact with the guide roller 33 in the high-ratio region as described above, Ratio, and increasing the contact area between the belt 13 and the guide roller 33 can reduce the wear caused by the contact between the belt 13 and the guide roller 33 .

When the belt-type continuously variable transmission B is applied to the power unit P of a motorcycle, the frequency of use of the continuously variable transmission B in the high-ratio region is more than that in the low-ratio region, so the frequency of use from the low-ratio region to the high-ratio region is higher. In the entire operating range of the proportional range, the wear of the belt 13 can be reduced as much as possible while ensuring a quiet effect.

Next, a second embodiment of the present invention will be described with reference to FIGS. 5 and 6. FIG.

Fig. 5 is a side view of main parts of a belt guide device of a belt-type continuously variable transmission, and Fig. 6 is a cross-sectional view along line 6-6 in Fig. 5, and the same symbols are used for the same components as those of the first embodiment above.

In this second embodiment, the structure of the outer member 139 of the guide roller 133 as a guide member is different from that of the first embodiment described above. That is, the guide roller 133 is formed by sintering and bonding an outer member 139 made of an elastic material such as rubber to the outer periphery of an inner member 138 made of metal such as Fe or Al having the same structure as the first embodiment. In the belt guide surface 143 on the outer periphery of the outer member 139, the first guide portion 143 ₁ constituted by a large-diameter protruding portion is integrally formed with a plurality of teeth 150 identical to the gear teeth along its entire circumference, so that the hardness of this portion is low. Easy to deform.

When the belt-type continuously variable transmission B is running in the low-ratio region, the inner peripheral surface of the belt 13 is in contact with the first guide part 1431 or the first guide part ₁₄₃₁ composed of a large-diameter protrusion with a plurality of teeth 150 across and obliquely. The guide part 143 ₁ and the second guide part 143 ₂ . When the belt 13 vibrates abnormally, the inner peripheral surface of the belt 13 buffers and contacts the belt guide surface 143 of the guide roller 133, and can reduce its contact area, thereby further reducing the contact knocking sound of the belt 13 to the guide roller 133, and improving Mute effect.

When the belt-type continuously variable transmission B operates in the high ratio range, if the belt 13 vibrates abnormally, the belt 13 contacts the flat second guide portion 243 ₂ as in the first embodiment above.

Next, a third embodiment of the present invention will be described with reference to FIGS. 7 and 8. FIG.

7 is a side view of main parts of a belt guide device of a belt-type continuously variable transmission, and FIG. 8 is a cross-sectional view along line 8-8 in FIG.

The third embodiment is a modification of the second embodiment, and the structure of the outer member 239 of the guide roller 233 as a guide member is different from the first embodiment described above. That is, the guide roller 233 is formed by sintering and bonding an outer member 239 made of an elastic material such as rubber to the outer periphery of an inner member 238 made of metal such as Fe or Al having the same structure as that of the first embodiment. On the outer peripheral surface of the outer member 239, that is, the entire area of the belt guide surface 243, that is, the first and second guide portions 243 ₁ , 243 ₂ , a plurality of teeth 250 identical to the gear teeth are integrally formed. The part corresponding to the part ₂₄₃₁ is deeper than the part corresponding to the second guide part ₂₄₃₂ , so that these teeth 250 are all of low hardness and easy to deform.

When the belt-type continuously variable transmission B is running in the low-ratio region, the inner peripheral surface of the belt 13 is in contact with the first guide part ₂₄₃₁ with a plurality of teeth or the first and second guides with a plurality of teeth. Section 243 ₁ , 243 ₂ . When the belt 13 vibrates abnormally, the inner peripheral surface of the belt 13 buffers and contacts the belt guide surface 243 of the guide roller 233, and can reduce its contact area, thereby further reducing the contact knocking sound of the belt 13 to the guide roller 233, and improving Mute effect. Even if the belt-type continuously variable transmission B operates in a high-ratio region, the belt 13 can buffer and contact the second guide portion 243 ₂ with a plurality of teeth 250 , further reducing the impact sound of the belt 13 .

Next, a fourth embodiment of the present invention will be described with reference to FIGS. 9 and 10 .

9 is a side view of main parts of the belt guide device of the belt-type continuously variable transmission B, and FIG. 10 is a cross-sectional view along line 10-10 in FIG.

This fourth embodiment differs from the first to third embodiments in that a fixed guide member is used as the guide member instead of the guide rollers of the first to third embodiments. That is to say, the guide member is composed of upper and lower fixed guide pieces 333u, 333d, and the upper and lower fixed guide pieces 333u, 333d are integrated from the box body 1 made of metal such as Fe, Al, etc. for accommodating the belt-type continuously variable transmission B. The inner surface of the outer cover 31 protrudes toward the inner side. This upper and lower fixed guide piece 333u, 333d is positioned at the middle part of driving pulley 4 and driven pulley 21, and is positioned at the inner side of endless belt 13, and the belt guide surface 343 of these upper and lower fixed guide piece 333u, 333d and belt 13 The inner peripheral surfaces of the upper and lower pulleys 4, 21 are in contact with the inner peripheral surface of the belt 13. Therefore, no matter what speed change position the belt 13 is in, the belt guide surfaces 343 of the upper and lower fixed guide pieces 333u, 333d The distance from the inner peripheral surface of the belt 13 does not change. In addition, as shown in FIG. 10, on the belt guide surfaces 343 of the above-mentioned pair of upper and lower fixed guide pieces 333u and 333d constituting the guide member, a flat high-level surface 3431 constituting the first guide portion and a flat high-level surface ₃₄₃₁ constituting the first guide portion are formed in a stepped manner. The flat lower surface 343 ₂ constituting the second guide portion has a smaller gap _d1 between the inner peripheral surface of the belt 13 and the above-mentioned upper surface 343 ₁ , and a larger gap _d2 between the inner peripheral surface of the belt 13 and the aforementioned lower surface 343 ₂ . . Same as the above-mentioned first embodiment, when the belt-type continuously variable transmission B operates in a low-ratio region with a large transmission ratio, as shown by the solid line in Figure 10, the belt 13 is located on the side of the case body 1, and its inner peripheral surface spans Opposite to the above-mentioned high-level surface (the first guide portion) ₃₄₃₁ and the low-level surface (the second guide portion) ₃₄₃₂ , when running in a high-ratio area with a small gear ratio, as shown by the dashed line in Figure 10, The belt 13 is located on a side away from the box body 1 , and its inner peripheral surface faces the flat lower surface 343 ₂ . Therefore, when the belt 13 is in the low proportion area, the gap _d1 between its inner peripheral surface and the upper and lower fixed guide pieces 333u, 333d is small; The gap _d2 between 333u and 333d is large.

When the belt-type continuously variable transmission B operates in a low-ratio area with a large transmission ratio, the belt 13 moves in parallel to the side of the box body 1, which is the position of the solid line in Figure 10, and the inner peripheral surface of the belt 13 is in contact with the upper and lower fixed guide The pieces 333u and 333d face each other, and the gap _d1 between the inner peripheral surface of the belt 13 and the upper and lower fixed guide pieces 333u and 333d is small. The upper and lower fixed guide pieces 333u, 333d have high-level surfaces 343 ₁ or their high-level surfaces 343 ₁ and low-level surfaces 343 ₂ , which can greatly reduce their contact area, and can carry out uneven contact, thereby effectively reducing the belt 13 contact guide. Belt slamming sound from components.

When the belt-type continuously variable transmission B operates in a high-ratio area with a small transmission ratio, as shown by the two-dot dash line in Figure 10, the belt 13 moves in parallel to the side away from the case body 1 side, and the inner circumference of the belt 13 The surface is opposite to the lower surface (second guide portion) ₃₄₃₂ of the upper and lower fixed guide pieces 333u, 333d. In this way, the gap _d2 between the inner peripheral surface of the belt 13 and the upper and lower fixed guide pieces 333u, 333d is larger than that of the above-mentioned low ratio area. When the belt 13 vibrates abnormally, the belt 13 contacts the upper and lower fixed guide pieces 333u, 333d. The frequency of the belt 13 is smaller than that in the above-mentioned low-ratio area, and since the inner peripheral surface of the belt 13 is in contact with the flat low-level surface 343 ₂ , the contact area is larger than that in the above-mentioned low-ratio area, thereby reducing the contact between the belt 13 and the upper surface. , The wear caused by the contact of the lower fixed guide pieces 333u, 333d.

Next, a fifth embodiment of the present invention will be described with reference to FIGS. 11 and 12. FIG.

11 is a side view of main parts of the belt guide device of the belt type continuously variable transmission B, and FIG. 12 is a cross-sectional view along line 12-12 in FIG.

This fifth embodiment is the case where the upper and lower fixing guide pieces of the above-mentioned fourth embodiment are arranged on the outside of the endless belt 13, and the upper and lower fixing guide pieces are integrally protruded from the inner surface of the box body 1 toward the inside. The guide pieces 433u and 433d are positioned between the drive pulley 4 and the driven pulley 21 and inside the endless belt 13 . On the belt guide surface 443 facing the outer peripheral surface of the belt 13 of the upper and lower fixed guide pieces 433u, 433d, a high-level surface 4431 as a first guide part and a high-level surface ₄₄₃₁ as a second guide part are formed by sandwiching a step in the same way as in the fourth embodiment. The lower plane of 443 ₂ .

In this fifth embodiment, when the belt 13 vibrates abnormally, its outer peripheral surface contacts the upper and lower fixed guide pieces 433u, 433d, and other structures and functions are the same as those of the fourth embodiment, so the description thereof is omitted.

The embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and various embodiments are possible within the scope of the present invention. For example, in the above-mentioned embodiments, although the belt guide device of the belt-type continuously variable transmission is implemented in the power unit for motorcycles, it goes without saying that it can also be implemented in other power units. In addition, as the guide member, Other equivalents may also be used instead of the fixed guides.

As described above, according to the first aspect of the present invention, in the belt-type continuously variable transmission, a guide member that can contact the peripheral surface of the belt when the belt vibrates abnormally is provided between the driving pulley and the driven pulley. There is a gap between the belt guide surface of the belt guide surface and the surrounding surface of the belt facing the belt guide surface. The gap is small when the belt is in the high speed ratio area and is large when the belt is in the low speed ratio area. Therefore, when the belt vibrates abnormally , the belt can be guided by the guide member, reducing the impact sound of the belt, avoiding unnecessary contact between the belt and the guide member, and improving the life of the belt.

According to the second aspect of the present invention, in the first aspect, the belt guide surface of the above-mentioned guide member has a first guide portion facing the belt in the high speed ratio range and a first guide portion facing the belt in the low speed ratio range. 2 Guide parts, the gap between the first guide part and the belt peripheral surface is small, the gap between the second guide part and the belt peripheral surface is large, and the strength of the first guide part is lower than that of the second guide part, so the above-mentioned effect On the basis of this, it is also possible to make the belt contact the guide member in a buffered manner, further reducing the belt knocking sound.

According to the third solution of the present invention, in the above-mentioned second solution, the above-mentioned first guide part is more biased to one side than the center of gravity of the belt section when the belt is in the high speed ratio region, so, on the basis of the above-mentioned effects, it is also possible to Tilting the belt to contact the guide member in a stepped manner further reduces belt rattling.

According to the fourth item of the present invention, in the above-mentioned items 1, 2, or 3, the above-mentioned guide member is composed of a guide roller, which can be freely rotatably arranged in the middle of the above-mentioned driving pulley and the driven pulley. The belt guide surface facing the inner peripheral surface of the above-mentioned belt is provided with the above-mentioned first guide part composed of a large-diameter convex part and the second guide part composed of a flat surface with a smaller diameter than it. Therefore, in On the basis of the above effects, when the belt is in contact with the guide roller, the guide roller turns, so that the wear of the belt and the guide roller can be further reduced.

According to the fifth aspect of the present invention, the above-mentioned guide member is integrally protruded from the case body surrounding the above-mentioned belt-type continuously variable transmission, and the guide portion facing the peripheral surface of the belt is formed with the above-mentioned first high-level surface. The guide part and the second guide part composed of the lower surface have a smaller gap between the above-mentioned high-level surface and the belt peripheral surface than the gap between the above-mentioned low-level surface and the belt peripheral surface. Therefore, on the basis of the above-mentioned effects, the guide member guiding the belt The upper and lower fixed guide pieces are integrally protruded from the box body, which can reduce the number of parts and assembly time, and greatly reduce the cost.

Claims (5)

1. A belt guide device for a belt-type continuously variable transmission, the belt-type continuously variable transmission is composed of a variable-diameter driving pulley (4) connected to the driving side, and a variable-diameter driven pulley (21) connected to the driven side 1. An endless belt (13) wound between the two pulleys (4, 21) constitutes a variable control of the winding diameter of the above two pulleys (4, 21) and the belt (13), which can be changed Gear ratio; characterized in that: a guide member (33; 133; 233) that can contact the peripheral surface of the belt (13) when the belt (13) vibrates abnormally is set between the driving pulley (4) and the driven pulley (21) ; 333u, 333d; 433u, 433d), between the belt guide surface of the guide member (33; 133; 233; 333u, 333d; 433u, 433d) and the peripheral surface of the belt (13) facing the belt guide surface A gap is set, and the gap is small when the belt (13) is in a high speed ratio region, and is large when the belt (13) is in a low speed ratio region. 2. The belt guide device of the belt-type continuously variable transmission according to claim 1, characterized in that: the belt guide surface of the above-mentioned guide member (33; 133; 233; 333u, 333d; 433u, 433d) has the above-mentioned belt (13) on The first guide portion (43 ₁ ; 143 ₁ ; 243 ₁ ; 343 ₁ ; 443 ₁ ) facing the high gear ratio area and the second guide portion (43 ₂ ; 143 ) facing the belt (13) in the low gear ratio area ₂ ; 243 ₂ ; 343 ₂ ; 443 ₂ ), the gap between the above-mentioned first guide part and the belt peripheral surface is small, the gap between the above-mentioned second guide part and the belt peripheral surface is large, and the strength of the first guide part is higher than that of the second guide part Department low. 3. The belt guide device of a belt-type continuously variable transmission according to claim 2, characterized in that: the first guide part (43 ₁ ; 143 ₁ ; 243 ₁ ; 343 ₁ ; 443 ₁ ) is at a higher speed than the belt (13) The center of gravity position of the belt (13) section during the zone is more biased to one side. 4. The belt guide device for belt-type continuously variable transmission according to claim 1, 2 or 3, characterized in that: the above-mentioned guide member (33; 133; 233) is composed of a guide roller, which is freely rotatably arranged on the above-mentioned driving pulley ( 4) In the middle of the driven pulley (21), there is a belt guide surface facing the inner circumference surface of the above-mentioned belt (13) on its outer peripheral surface. A guide portion (43 ₁ ; 143 ₁ ; 243 ₁ ) and a second guide portion (43 ₂ ; 143 ₂ ; 243 ₂ ) formed of a flat surface with a smaller diameter than the guide portion. 5. The belt guide device of the belt-type continuously variable transmission according to claim 1, 2 or 3, characterized in that: the above-mentioned guide members (333u, 333d; 433u, 433d) from ) is integrally protruded and formed, and the belt guide surface facing the peripheral surface of the belt (13) is formed with the above-mentioned first guide portion (343 ₁ ; 443 ₁ ) composed of a high-level surface and the second guide portion composed of a low-level surface. Guide part (343 ₂ ; 443 ₂ ), the gap between the first guide part (343 ₁ ; 443 ₁ ) and the belt (13) circumference is larger than the gap between the second guide part (343 ₂ ; 443 ₂ ) and the belt (13) circumference The surface gap is small.

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